<clinical_study>
  <!-- This xml conforms to an XML Schema at:
    https://clinicaltrials.gov/ct2/html/images/info/public.xsd -->
  <required_header>
    <download_date>ClinicalTrials.gov processed this data on September 20, 2023</download_date>
    <link_text>Link to the current ClinicalTrials.gov record.</link_text>
    <url>https://clinicaltrials.gov/ct2/show/NCT03043469</url>
  </required_header>
  <id_info>
    <org_study_id>1468-NHS-Dec/2016- 4775-1</org_study_id>
    <nct_id>NCT03043469</nct_id>
  </id_info>
  <brief_title>Dysfunctional Breathing: Characterisation and Assessment</brief_title>
  <official_title>Dysfunctional Breathing: Multidimensional Characterisation and Assessment Tool</official_title>
  <sponsors>
    <lead_sponsor>
      <agency>Brunel University</agency>
      <agency_class>Other</agency_class>
    </lead_sponsor>
    <collaborator>
      <agency>University of Sao Paulo</agency>
      <agency_class>Other</agency_class>
    </collaborator>
  </sponsors>
  <source>Brunel University</source>
  <oversight_info>
    <has_dmc>No</has_dmc>
    <is_fda_regulated_drug>No</is_fda_regulated_drug>
    <is_fda_regulated_device>No</is_fda_regulated_device>
  </oversight_info>
  <brief_summary>
    <textblock>
      Dysfunctional breathing (DB) is a respiratory condition characterised by an abnormal&#xD;
      breathing pattern, among other complaints, that can occur either in the absence of other&#xD;
      pathophysiology (primary DB), e.g. anxiety-related factors, or secondary to cardiopulmonary&#xD;
      disease (secondary DB), e.g. asthma. As a consequence, patients may experience breathlessness&#xD;
      and present with periods of increased ventilation or erratic breathing, interspersed with&#xD;
      episodes of breath holding or deep sighs. In addition to respiratory symptoms, DB also&#xD;
      generates non- respiratory symptoms (e.g. dizziness and increased heart rate). It is&#xD;
      estimated 1 in 10 people in the United Kingdom (UK) have DB. However, DB remains poorly&#xD;
      understood, with no standardised approach to diagnosis and assessment.&#xD;
&#xD;
      The purposes of this study are:&#xD;
&#xD;
      Study 1) To identify physiological, functional and psychological characteristics of&#xD;
      participants with DB compared to healthy participants.&#xD;
&#xD;
      Firstly, symptoms, lung function, respiratory gas analysis, exercise capacity, respiratory&#xD;
      muscle function, respiratory motion, level of physical activity, quality of life and anxiety&#xD;
      &amp; depression scores will be assessed in 20 participants with primary DB, 20 with secondary DB&#xD;
      and compared to 20 healthy participants.&#xD;
&#xD;
      Study 2) To develop an assessment tool based on physiological, functional or psychological&#xD;
      variables found to be different between any of the 3 groups in Study 1.&#xD;
&#xD;
      In order to do that, 54 people with DB (between primary and secondary) and 27 people&#xD;
      presenting with breathlessness secondary to restrictive lung disease will be assessed.&#xD;
      Analysis of these data will determine whether these variables can be used as a diagnostic&#xD;
      tool capable of distinguishing DB from restrictive lung diseases characterised by&#xD;
      breathlessness.&#xD;
&#xD;
      The recruitment period will be 1-2 years, with an individual participation of 9 days; 1-day&#xD;
      on site testing, plus 7-day home activity monitoring, and 1 day to return the activity&#xD;
      monitor (which will happen whenever the participant needs to return to the site).&#xD;
    </textblock>
  </brief_summary>
  <detailed_description>
    <textblock>
      In this research, the aims are: 1) to characterise and compare participants with primary&#xD;
      dysfunctional breathing (DB), secondary DB and healthy participants, 2) to develop an&#xD;
      assessment and identification tool for the population with DB, 3) to identify subgroups of&#xD;
      people with DB based on their functional, physiological and psychological characteristics.&#xD;
&#xD;
      In order to do that, in Study 1, there will be a comparison of many different aspects&#xD;
      (described below) between three groups of 20 participants each: primary DB, secondary DB and&#xD;
      healthy participants. With the results of these comparisons, it will be possible to know more&#xD;
      about the differences people with DB have in relation to the healthy population, and to&#xD;
      describe their main characteristics. Based on that, in Study 2, it will be possible to select&#xD;
      the variables that are different between groups and replicate those tests in an extra 54&#xD;
      participants DB (primary and secondary) and 27 with breathlessness secondary to restrictive&#xD;
      lung disease (DB excluded). The second stage will suggest tests to be used when identifying&#xD;
      and evaluating this population, and statistically identify subgroups of people with DB based&#xD;
      on their characteristics.&#xD;
&#xD;
      It is important to note why the inclusion of healthy participants and participants with&#xD;
      breathlessness secondary to restrictive lung disease is important in this research programme.&#xD;
      Firstly, it is essential to know the main characteristics of DB in relation to the healthy&#xD;
      population. Secondly, the assessment tool has to be able to suggest probability of negative&#xD;
      diagnosis of DB for people who do not have DB, and not only positive diagnosis for those who&#xD;
      have.&#xD;
&#xD;
      There are no standardised criteria available to diagnose DB. However, experienced chest&#xD;
      physicians at Guy's and St Thomas' Foundation Trust (GSTFT) identify probable DB, and provide&#xD;
      a clinical diagnosis (CD) according to the following criteria: patients presenting with&#xD;
      symptoms that are not concordant with the severity of the underlying health condition (in&#xD;
      case of secondary DB), patients presenting with symptoms that persist despite optimal disease&#xD;
      management and/or no objective markers of deterioration/exacerbation (in case of secondary&#xD;
      DB), patients presenting with symptoms in the presence of negative tests for organic&#xD;
      cause/medically unexplained (in case of primary DB), patients presenting with symptoms that&#xD;
      are considered functional (in case of primary DB).&#xD;
&#xD;
      Ability to comprehend and/or perform the procedures of this research, as well as the presence&#xD;
      of major orthopaedic, neurological or cardiac conditions will be checked by Leyla Osman and&#xD;
      the Chest physicians via medical records and when the possible participant is approached to&#xD;
      receive information about the study. For example: health conditions in which patients present&#xD;
      with an impairment of mental faculties and/or motor function (inability to cycle with no&#xD;
      discomfort).&#xD;
&#xD;
      Healthy participants will be contacted via email list at Brunel University London, and via&#xD;
      flyers placed on the University's and Hospital's website and murals (attached). Participants&#xD;
      with restrictive lung disease will be reached in person or via telephone call when they are&#xD;
      referred to respiratory physiotherapy, or via flyers placed on the Hospital's murals. Because&#xD;
      there are not plenty of patients with DB, those who are already registered on the Hospital's&#xD;
      system as presenting with DB (assessed by a chest physician) will be called. New patients&#xD;
      with DB will be contacted in person or via telephone call by the respiratory physiotherapist&#xD;
      of the clinical team (Leyla Osman).&#xD;
&#xD;
      If those contacted about this research are interested in taking part in this study, they will&#xD;
      be provided with the participant information sheet, have the opportunity to ask any questions&#xD;
      they may have and it will be checked if they meet the inclusion criteria. Before starting the&#xD;
      assessments, they will be asked to sign the informed consent.&#xD;
&#xD;
      When signing the informed consent, participants will be asked a few questions:&#xD;
&#xD;
      Please, tick this box if you authorise the researchers of this study to have access to your&#xD;
      medical records Please, tick this box if you are aware that your General practitioner will be&#xD;
      informed about your participation in this research Please, tick this box if you would like to&#xD;
      receive a report with your results of the tests performed in this study (within 30 days from&#xD;
      the end of your assessments) Please, tick this box if you would like us to contact you in the&#xD;
      future to inform you about the final results of this study Please, tick this box if you are&#xD;
      participating in other study/ies at this moment. If yes, please mention below what this/these&#xD;
      study/ies is/are about and the contact of the person responsible for it The assessments will&#xD;
      be performed by Lais Silva Vidotto (respiratory physiotherapist and researcher) at the&#xD;
      Hospital/University over a period of approximately 3 hours. Many of these assessments form&#xD;
      part of routine hospital investigations for patients with DB. Duration may vary depending on&#xD;
      individual needs and limitations, such as time given to recover from any physical or mental&#xD;
      effort. Secondly, a physical activity monitor will be given to all participants, which will&#xD;
      be returned to the researchers on the next medical appointment at the Hospital/classes at the&#xD;
      University (classes at the University in case of healthy participants). During the 3-hour&#xD;
      assessment they will have the opportunity to rest whenever is necessary and snacks and&#xD;
      refreshments will be provided in the intervals (caffeine-free ingredients).&#xD;
&#xD;
      Assessments and their approximate duration are as follows: demographic information (10&#xD;
      minutes), health-related quality of life questionnaire (SF-36) (5 minutes), Hospital anxiety&#xD;
      and depression scale (HADS) (5 minutes), Nijmegen questionnaire (NQ) (5 minutes),&#xD;
      Self-evaluation of breathing questionnaire (SEBQ) (5 minutes), Asthma Questionnaire (only for&#xD;
      asthmatics) (5 minutes), lung function test (30 minutes), respiratory muscle function (30&#xD;
      minutes, assessment of the respiratory movements (MARM) (10 minutes), breath-hold test (BHT)&#xD;
      (20 minutes), slow-breathing task (15 minutes) and the sub-maximal exercise test (10 minutes)&#xD;
      (during the two last tests participants will be wearing small and light-weight devices that&#xD;
      monitor heart activity, breathing function and blood pressure and take 15 minutes to be&#xD;
      placed all together).&#xD;
&#xD;
      Day 1: Hospital assessments (~3 hours) The tests will be performed in a private room at St&#xD;
      Thomas' Hospital or Brunel University London. Participants will be advised to stay 48 hours&#xD;
      without practicing exercise. Also, they will be instructed to take all the medicines they&#xD;
      normally use and to report their names and doses to the examiner.&#xD;
&#xD;
        1. Patients will be asked about their medical history, date of birth and symptoms. Also,&#xD;
           participants' weight and height will be measured.&#xD;
&#xD;
        2. Chest movements while breathing:&#xD;
&#xD;
           At this stage, participants are going to stand still while the researcher will place&#xD;
           their hands on the back of their chests in order to evaluate its movements while&#xD;
           participants are breathing. This is going to take about 10 minutes.&#xD;
&#xD;
        3. Slow-breathing task:&#xD;
&#xD;
           Participants will be instructed on how to breathe slower (6-10 bpm) for a few minutes&#xD;
           (5-15 minutes) and will keep wearing the mask, the heart rate monitor and the arterial&#xD;
           blood pressure monitor during this task.&#xD;
&#xD;
        4. Exercise test, breathing and cardiovascular function:&#xD;
&#xD;
           Light-weight devices will be attached to participants' chest (cardiac monitor), in order&#xD;
           to evaluate heart function, to their faces (mask-gas analyser) to assess respiratory&#xD;
           function, and to their non-dominant arm (arm and finger), to assess blood pressure. The&#xD;
           device used to assess blood pressure continuously measures the pulse of the finger,&#xD;
           calibrated by an arm cuff, with no discomfort to the participant. Those assessments will&#xD;
           be performed while participants rest for five minutes, while they cycle on a bicycle&#xD;
           with moderate resistance for six minutes, and while they rest for five more minutes.&#xD;
           Just before the exercise test, at the third minute, and just after it, participants will&#xD;
           be asked about any leg or breathing discomfort and how mindful they are in relation to&#xD;
           discomfort related to the task. Approximate time of this task: 16 minutes.&#xD;
&#xD;
        5. Questionnaires:&#xD;
&#xD;
           Participants will be asked to fill in some questionnaires that will ask about their&#xD;
           breathing and quality of life and will take about 25 minutes to complete. Participants&#xD;
           will be asked to complete these questionnaires after having the opportunity to ask&#xD;
           questions about them.&#xD;
&#xD;
        6. Breath hold test:&#xD;
&#xD;
           Participants will be asked to hold their breath for as long as they can for 3 times,&#xD;
           resting for 5 minutes after each one of them, and the researcher will use a stopwatch in&#xD;
           order to count the time they are able to do it. The whole task will last in&#xD;
           approximately 20 minutes.&#xD;
&#xD;
        7. Lung and respiratory muscle function assessments:&#xD;
&#xD;
      Researchers will use three devices to measure the function of participants' lungs and&#xD;
      respiratory muscles. They will be asked to breathe in and out in several different ways,&#xD;
      wearing a nose clip, so that researchers can record their general breathing function. This is&#xD;
      going to take about one hour to finish.&#xD;
&#xD;
      At the end of the assessment session, participants will be instructed on how to use a device&#xD;
      that measures the level of physical activity.&#xD;
&#xD;
      Days 2-8: Physical Activity Monitoring Participants will be asked to wear two small activity&#xD;
      monitors attached to their hip for 7 consecutive days, keeping their routine as normal as&#xD;
      possible. Participants will have to use the equipment for at least 8 hours/day while they are&#xD;
      awake, excluding water activities (e.g. shower) and sleeping, writing down the exact time&#xD;
      they put it on and the time they took this off.&#xD;
&#xD;
      Day 9: Return of the activity monitors Participants recruited from Brunel University London&#xD;
      will return their physical activity monitors to the researchers on their next visit to the&#xD;
      University (for classes, meetings etc.); those recruited from GSTFT will return it on their&#xD;
      next hospital appointment.&#xD;
&#xD;
      Although this study requires a cross-sectional design, it may take a long period to be&#xD;
      completed, since patients with DB are not easily identified and referred to other health&#xD;
      professionals to receive specific diagnosis or treatment. Considering this difficulty in&#xD;
      finding participants with DB, justified by the fact that there is no established way of&#xD;
      identifying these patients, this research may take 1-2 years to be completed. However, It&#xD;
      will enable the researchers to look at every single result and be rigorous with the quality&#xD;
      of the data collected. In order to do that, the researchers will not wait for all assessments&#xD;
      to be finished to process and plot the data. Every time a participant is evaluated, their&#xD;
      results will be organised and plotted within the next few days. It will also enable the data&#xD;
      to be statistically analysed when needed.&#xD;
    </textblock>
  </detailed_description>
  <overall_status>Unknown status</overall_status>
  <last_known_status>Not yet recruiting</last_known_status>
  <start_date type="Anticipated">August 8, 2020</start_date>
  <completion_date type="Anticipated">May 30, 2021</completion_date>
  <primary_completion_date type="Anticipated">April 30, 2021</primary_completion_date>
  <study_type>Observational</study_type>
  <has_expanded_access>No</has_expanded_access>
  <study_design_info>
    <observational_model>Case-Control</observational_model>
    <time_perspective>Cross-Sectional</time_perspective>
  </study_design_info>
  <primary_outcome>
    <measure>Signs of Anxiety and Depression</measure>
    <time_frame>This scale will be applied only once during the first day of assessment and takes about 5 minutes for the participant to complete.</time_frame>
    <description>Anxiety and depression will be evaluated by the widely used Hospital Anxiety and Depression Scale (HADS), developed by Zigmond and Snaith (1983) to identify and screen cases of anxiety and depression in non-psychiatric environments. It has been proven to be a valid psychological instrument (Bjelland et al. 2002). The HADS is subdivided into two subscales with seven questions each: Anxiety (HADS-A) and Depression (HADS-B). Therefore, it is able to differentiate anxiety from depression possible/probable disorders.</description>
  </primary_outcome>
  <primary_outcome>
    <measure>Levels of subjective sensation related to Hyperventilation Syndrome</measure>
    <time_frame>This scale will be applied only once and takes about 5 minutes to be completed by the participant.</time_frame>
    <description>The Nijmegen Questionnaire is a clinically used tool for analysis of 16 symptoms related to Hyperventilation syndrome arising from different body systems (such as chest pain, blurred vision and faster or deeper breathing). The participant will choose the answer from a 5-point ordinal scale considering the frequency of symptoms. 23 of 64 points or more is considered positive for abnormality of subjective sensations (van Dixhoorn and Folgering 2015) and correlates positively with Dysfunctional Breathing (Vansteenkiste, Rochette, Demedt, 1991).</description>
  </primary_outcome>
  <primary_outcome>
    <measure>Self-evaluation of breathing</measure>
    <time_frame>This scale will be applied only once and takes about 5 minutes to be completed by the participant..</time_frame>
    <description>The Self Evaluation Breathing Questionnaire is a reliable tool developed by Courtney and Greenwood (2009) to assess breathing pattern of participants with Dysfunctional Breathing (Mitchell et al. 2015). It contains 17 items that are answered using a 4-point Likert scale and includes two main factors: &quot;lack of air&quot;, which is about feeling and sensing; and &quot;perception of inappropriate or restricted breathing&quot;, which is about observing or noticing. It has been indicated that the higher the SEBQ score, the more severe is the clinical condition of Dysfunctional Breathing (Mitchell et al. 2015). However, researchers who created the SEBQ questionnaire suggested that it can be used as a screening tool for identifying Dysfunctional Breathing and for monitoring changes in breathing symptoms after treatment, but there is no normal value available in the literature for this questionnaire yet (Courtney, Greenwood, et al. 2011).</description>
  </primary_outcome>
  <primary_outcome>
    <measure>Respiratory Motion</measure>
    <time_frame>This assessment will be applied only once and takes about 10 minutes to be completed.</time_frame>
    <description>The Manual Assessment of Respiratory Motion (MARM) will be used to assess thoracic and diaphragmatic movements during breathing and quantify their contribution as a percentage of the total breathing movement. During this evaluation, the examiner will position their open hands between posterior and lateral lower rib cage (lower four to six ribs) and the thumbs will vertically be positioned about 1 inch from the spine. In this position, it is possible for the examiner to identify lateral and vertical movements during breathing, as well as upper or lower rib cage predominance. The examiner will draw an upper, lower and horizontal lines starting from the centre of a circle, building a pie chart with the degree of expansion (Courtney et al. 2008, Courtney and van Dixhoorn 2014). A perfect balance between thoracic and abdominal motion during breathing presents a MARM between 0 and 6; as well as a value above 30 may be considered as dysfunctional (Courtney et al. 2011; Courtney et al. 2008).</description>
  </primary_outcome>
  <primary_outcome>
    <measure>Breath-holding time</measure>
    <time_frame>This assessment will be applied only once and takes about 20 minutes to be completed.</time_frame>
    <description>In the Breath-hold test, the variable considered is the total time the participant is able to hold a breath after a normal exhalation at functional residual capacity. This standardized protocol used in participants with DB is called the Buteyko Method of the Control Pause, where the breath is held and timed until the first involuntary motion of the respiratory muscles (Courtney and Cohen 2008). The breath-holding time has been estimated to be approximately 20 seconds patients with DB, while in healthy people is approximately 60 seconds (Jack et al. 2004, Courtney and Cohen 2008). Three attempts will be undertaken with 5-minute rest in between; a stopwatch will be used to time each one, as well as the intervals. The mean of the three attempts will be analysed, in order to remove any learnt effect (Courtney, Greenwood, et al. 2011).</description>
  </primary_outcome>
  <secondary_outcome>
    <measure>Medical History</measure>
    <time_frame>This assessment will be applied during the 3-hour assessment, and takes about 5 minutes to be completed.</time_frame>
    <description>Participants will be asked about their medical history, health conditions, comorbidities, medicines in use and its doses.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Age</measure>
    <time_frame>This assessment will be applied during the 3-hour assessment, and takes about 20 seconds to be completed.</time_frame>
    <description>The date of birth (age) of the participants will be recorded and used for analyses.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Gender</measure>
    <time_frame>This assessment will be applied during the 3-hour assessment, and takes about 10 seconds to be completed.</time_frame>
    <description>The gender of the participants will be recorded and used for analyses.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Weight</measure>
    <time_frame>This assessment will be applied during the 3-hour assessment, and takes about 10 seconds to be completed.</time_frame>
    <description>The weight of the participants will be recorded based on self-report.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Height</measure>
    <time_frame>This assessment will be applied during the 3-hour assessment, and takes about 10 seconds to be completed.</time_frame>
    <description>The height of the participants will be recorded based on self-report.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Body mass index (BMI)</measure>
    <time_frame>The BMI will be calculated based on height and weight collected from the participants, and will take about 1 minute to be calculated.</time_frame>
    <description>The body mass index of the participants will be calculated as follows: weight over height squared.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Level of physical activity</measure>
    <time_frame>This assessment will be applied during the 3-hour assessment, and takes about 3 minutes to be completed.</time_frame>
    <description>The level of physical activity of the participants will be recorded based on self-report. They will be asked how many days of a typical week they participate in moderate-to-vigorous physical activity. Also, they will be asked how many minutes per day, during a typical week, they participate in moderate-to-vigorous physical activity. Finally, participants will be asked about any sports that they have participated in and at what level.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Forced vital capacity (FVC)</measure>
    <time_frame>This assessment will be applied during the 3-hour assessment, and takes about 10 minutes to be completed.</time_frame>
    <description>Lung function will be assessed by spirometry, as hypocapnia is associated with bronchoconstriction (Combes and Fauvage 1997, Brijker et al. 2001). Forced vital capacity (FVC) will be assessed following international recommendations (Miller et al. 2005) and the reference values will be calculated according to Quanjer et al. (1993) and Stanojevic et al. (2010). The participant will be instructed to exhale the maximum possible until residual volume and to inspire as rapid as possible, aiming a maximal and quick gasp until at least 50% of vital capacity.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Forced expiratory volume in the first second (FEV1)</measure>
    <time_frame>This assessment will be applied during the 3-hour assessment, and takes about 10 minutes to be completed.</time_frame>
    <description>Lung function will be assessed by spirometry, as hypocapnia is associated with bronchoconstriction (Combes and Fauvage 1997, Brijker et al. 2001). Forced expiratory volume in the first second (FEV1) will be assessed following international recommendations (Miller et al. 2005) and the reference values will be calculated according to Quanjer et al. (1993) and Stanojevic et al. (2010). The participant will be instructed to exhale the maximum possible until residual volume and to inspire as rapid as possible, aiming a maximal and quick gasp until at least 50% of vital capacity.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Maximum voluntary ventilation (MVV)</measure>
    <time_frame>This assessment will be applied during the 3-hour assessment, and takes about 10 minutes to be completed.</time_frame>
    <description>Lung function will be assessed by spirometry, as hypocapnia is associated with bronchoconstriction (Combes and Fauvage 1997, Brijker et al. 2001). Forced expiratory volume in the first second (FEV1) will be assessed following international recommendations (Miller et al. 2005) and the reference values will be calculated according to Quanjer et al. (1993) and Stanojevic et al. (2010). The participant will be instructed to ventilate with her or his maximal ventilation volume and frequency, inhaling and exhaling as deep and quick as possible.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Peak inspiratory flow rate</measure>
    <time_frame>This assessment will be applied during the 3-hour assessment, and takes about 10 minutes to be completed (together with the FVC, since this outcome is provided by the same manoeuvre).</time_frame>
    <description>The peak inspiratory flow rate will be measured based on the protocol described by McConnell (McConnell 2013). The participant will be instructed to exhale the maximum possible until residual volume and to inspire as rapid as possible, aiming a maximal and quick gasp until at least 50% of vital capacity.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Peak expiratory flow rate</measure>
    <time_frame>This assessment will be applied during the 3-hour assessment, and takes about 10 minutes to be completed.</time_frame>
    <description>The peak expiratory flow rate will be measured based on the protocol described by McConnell (McConnell 2013). The participant will be instructed to inhale the maximum possible until total vital capacity and to expire as rapid as possible, aiming a maximal and quick manoeuvre.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Inspiratory muscle function</measure>
    <time_frame>This assessment will be applied during the 3-hour assessment, and takes about 30 minutes to be completed.</time_frame>
    <description>Inspiratory muscle strength will be assessed by the maximal inspiratory pressure (MIP) measurement (McConnell and Copestake 1999, Volianitis et al. 2001) using a mouth pressure meter (Micro Medical RPM, Carefusion, San Diego, United States). The protocol to assess inspiratory muscle strength will be the one described by Black and Hyatt (1969), in which MIP is measured starting at residual volume (McConnell 2013). During the manoeuvre the participants will be instructed to sustain a maximal effort for at least 1.5-2.0 seconds, and a minimum of 5 satisfactory efforts will be considered according to Volianitis et al. (2001).</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Expiratory muscle function</measure>
    <time_frame>This assessment will be applied during the 3-hour assessment, and takes about 30 minutes to be completed.</time_frame>
    <description>Expiratory muscle strength will be assessed by the maximal expiratory pressure (MEP) measurement (McConnell and Copestake 1999, Volianitis et al. 2001) using a mouth pressure meter (Micro Medical RPM, Carefusion, San Diego, United States). The protocol to assess expiratory muscle strength will be the one described by Black and Hyatt (1969), in which MEP is measured starting at total lung capacity (McConnell 2013). During the manoeuvre the participants will be instructed to sustain a maximal effort for at least 1.5-2.0 seconds, and a minimum of 5 satisfactory efforts will be considered according to Volianitis et al. (2001).</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Exercise capacity</measure>
    <time_frame>This assessment will be applied during the 3-hour assessment, and takes about 16 minutes to be completed (simultaneously with the levels of heart rate variability, arterial blood pressure and gas exchange).</time_frame>
    <description>The Astrand-Ryhming submaximal test (Astrand and Ryhming 1954) will be used to assess exercise capacity of all participants and to predict maximal oxygen uptake. Participants will be instructed to stay 48 hours previous to the test without practicing exercise. This test will be performed on a cycle ergometer and power outputs of 75 to 150 watts and 100 to 200 watts will be used for women and men, respectively. The rotation of 50 rpm needs to be kept for 6 minutes. The HR is registered at the 5th and 6th minutes of the exercise test, and with the right load, these values cannot differentiate from each other more than 5 bpm. After that, a mathematic model will be used to predict the maximal oxygen uptake (Astrand and Ryhming 1954, Legge and Banister 1986, Macsween 2001).</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Level of heart rate variability</measure>
    <time_frame>This assessment will be applied during the 3-hour assessment, and takes about 15 minutes to be placed and will be continuously used during the exercise test (16 minutes) and the slow-breathing task (15 minutes).</time_frame>
    <description>The heart rate variability (HRV) will be continuously assessed during five minutes before, during, and five minutes after the exercise test and during a controlled breathing of approximately 6-10 breaths per minute. HRV will be assessed by using a Polar® V800 device (Polar, Kempele-Finland), and the heart's electrical signal will be processed by using Kubios HRV version 2.2. The data will be initially filtered and smoothed to obtain heart rate frequency mean, time-domain analyses of the R-R intervals (interval between 2 &quot;R&quot; curves in the electrocardiogram (e.g., standard deviation of normal-to-normal RR intervals [SDNN] and root mean square of successive differences [RMSSD]) and spectral analyses of frequency indices (i.e., very low-frequency [0-0.04], low-frequency [0.04-0.15 Hz] and high-frequency [0.15-0.4 Hz]) aiming the further understanding of the autonomic nervous system responses in DB.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Level of arterial blood pressure</measure>
    <time_frame>This assessment will be applied during the 3-hour assessment, and takes about 15 minutes to be placed and will be continuously used during the exercise test (16 minutes) and the slow-breathing task (15 minutes).</time_frame>
    <description>The arterial blood pressure (ABP) will be continuously assessed during five minutes before, during, and five minutes after the exercise test and during a controlled breathing of approximately 6-10 breaths per minute. Finger ABP will be measured by the use of Finometer 1.10 (Finapres Medical System, Amsterdam - The Netherlands), which non-invasively registers continuous blood pressure measurements. The finger pressure generates a waveform and the ABP is exported based on calculations built every heartbeat (Bogert and van Lieshout 2005). Finger ABP signals will be processed by using the Lab Chart Pro Software, which records, displays and analyses real time data from up to 32 channels.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Minute volume</measure>
    <time_frame>This assessment will be applied during the 3-hour assessment, and takes about 15 minutes to be placed and will be continuously used during the exercise test (16 minutes) and the slow-breathing task (15 minutes).</time_frame>
    <description>The indirect calorimetry (IC) will be performed by the portable system K5® (Cosmed, Rome, Italy). This ergospirometer calculates breath-by-breath oscillations of minute volume (VE). The device will be attached to the participant's chest and a facemask, which has less than 30 ml of dead space, suitably adjusted to eliminate air leakage. The equipment will be programmed to assess data breath-by-breath and an average will be recorded every 5 seconds. Oxycon Pro software will be used to process the data for further analyses.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Oxygen Uptake</measure>
    <time_frame>This assessment will be applied during the 3-hour assessment, and takes about 15 minutes to be placed and will be continuously used during the exercise test (16 minutes) and the slow-breathing task (15 minutes).</time_frame>
    <description>The indirect calorimetry (IC) will be performed by the portable system K5® (Cosmed, Rome, Italy). This ergospirometer calculates breath-by-breath oscillations of oxygen uptake (O2). The device will be attached to the participant's chest and a facemask, which has less than 30 ml of dead space, suitably adjusted to eliminate air leakage. The equipment will be programmed to assess data breath-by-breath and an average will be recorded every 5 seconds. Oxycon Pro software will be used to process the data for further analyses.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Carbon dioxide</measure>
    <time_frame>This assessment will be applied during the 3-hour assessment, and takes about 15 minutes to be placed and will be continuously used during the exercise test (16 minutes) and the slow-breathing task (15 minutes).</time_frame>
    <description>The indirect calorimetry (IC) will be performed by the portable system K5® (Cosmed, Rome, Italy). This ergospirometer calculates breath-by-breath oscillations of carbon dioxide (CO2). The device will be attached to the participant's chest and a facemask, which has less than 30 ml of dead space, suitably adjusted to eliminate air leakage. The equipment will be programmed to assess data breath-by-breath and an average will be recorded every 5 seconds. Oxycon Pro software will be used to process the data for further analyses.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Respiratory exchange ratio</measure>
    <time_frame>This assessment will be applied during the 3-hour assessment, and takes about 15 minutes to be placed and will be continuously used during the exercise test (16 minutes) and the slow-breathing task (15 minutes).</time_frame>
    <description>The indirect calorimetry (IC) will be performed by the portable system K5® (Cosmed, Rome, Italy). This ergospirometer calculates breath-by-breath oscillations of respiratory exchange ratio (RER). The device will be attached to the participant's chest and a facemask, which has less than 30 ml of dead space, suitably adjusted to eliminate air leakage. The equipment will be programmed to assess data breath-by-breath and an average will be recorded every 5 seconds. Oxycon Pro software will be used to process the data for further analyses.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Respiratory rate</measure>
    <time_frame>This assessment will be applied during the 3-hour assessment, and takes about 15 minutes to be placed and will be continuously used during the exercise test (16 minutes) and the slow-breathing task (15 minutes).</time_frame>
    <description>The indirect calorimetry (IC) will be performed by the portable system K5® (Cosmed, Rome, Italy). This ergospirometer calculates breath-by-breath oscillations of respiratory rate (breaths per minute - BPM). The device will be attached to the participant's chest and a facemask, which has less than 30 ml of dead space, suitably adjusted to eliminate air leakage. The equipment will be programmed to assess data breath-by-breath and an average will be recorded every 5 seconds. Oxycon Pro software will be used to process the data for further analyses.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Attentional focus</measure>
    <time_frame>This assessment will be applied 3 times during the exercise test, and takes about 30 seconds to be completed each time. So, it will take approximately 1 minute and 30 seconds to be applied in total.</time_frame>
    <description>Attentional focus (Attention Scale [AS]; Tammen 1996, Tenenbaum et al. 2007) will be measured at various time points (pre exercise, at the 3rd minute, and at the end of the exercise test) during the execution of the six-minute cycling test described above.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Level of fatigue</measure>
    <time_frame>This assessment will be applied 3 times during the exercise test, and takes about 15 seconds to be completed each time. So, it will take approximately 45 seconds to be applied in total.</time_frame>
    <description>Limb discomfort (Category Ratio 10 [CR10-fatigue]; Borg 1982) (Borg Scale fatigue) will be measured at various time points (pre exercise, at the 3rd minute, and at the end of the exercise test) during the execution of the six-minute cycling test described above.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Level of dyspnoea</measure>
    <time_frame>This assessment will be applied 3 times during the exercise test, and takes about 15 seconds to be completed each time. So, it will take approximately 45 seconds to be applied in total.</time_frame>
    <description>Dyspnoea (CR10-dyspnoea; Borg 1982) (Borg Scale dyspnoea) will be measured at various time points (pre exercise, at the 3rd minute, and at the end of the exercise test) during the execution of the six-minute cycling test described above.</description>
  </secondary_outcome>
  <number_of_groups>4</number_of_groups>
  <enrollment type="Anticipated">141</enrollment>
  <condition>Respiration Disorder</condition>
  <condition>Hyperventilation Syndrome</condition>
  <condition>Breathlessness</condition>
  <condition>Breath Shortness</condition>
  <arm_group>
    <arm_group_label>Healthy participants</arm_group_label>
    <description>Day 1: Hospital assessments (~3 hours): Demographic data, Manual Assessment of Respiratory Motion, Slow-breathing task, Six-minute exercise test, Indirect calorimetry, Oxygen saturation monitoring, heart rate variability analysis, continuous measurement of arterial blood pressure, lung function test, the Nijmegen Questionnaire and the Self-Evaluation of Breathing Questionnaire, the Hospital anxiety and depression scale, and the Short-Form Survey Instrument, Breath-hold test, Lung function test, respiratory muscle function assessment.&#xD;
Days 2-8: Physical Activity Monitoring</description>
  </arm_group>
  <arm_group>
    <arm_group_label>Restrictive lung disease group</arm_group_label>
    <description>Day 1: Hospital assessments (~3 hours): Demographic data, Manual Assessment of Respiratory Motion, Slow-breathing task, Six-minute exercise test, Indirect calorimetry, Oxygen saturation monitoring, heart rate variability analysis, continuous measurement of arterial blood pressure, lung function test, the Nijmegen Questionnaire and the Self-Evaluation of Breathing Questionnaire, the Hospital anxiety and depression scale, and the Short-Form Survey Instrument, Breath-hold test, Lung function test, respiratory muscle function assessment.&#xD;
Days 2-8: Physical Activity Monitoring</description>
  </arm_group>
  <arm_group>
    <arm_group_label>Primary dysfunctional Breathing group</arm_group_label>
    <description>Day 1: Hospital assessments (~3 hours): Demographic data, Manual Assessment of Respiratory Motion, Slow-breathing task, Six-minute exercise test, Indirect calorimetry, Oxygen saturation monitoring, heart rate variability analysis, continuous measurement of arterial blood pressure, lung function test, the Nijmegen Questionnaire and the Self-Evaluation of Breathing Questionnaire, the Hospital anxiety and depression scale, and the Short-Form Survey Instrument, Breath-hold test, Lung function test, respiratory muscle function assessment.&#xD;
Days 2-8: Physical Activity Monitoring</description>
  </arm_group>
  <arm_group>
    <arm_group_label>Secondary dysfunctional breathing group</arm_group_label>
    <description>Day 1: Hospital assessments (~3 hours): Demographic data, Manual Assessment of Respiratory Motion, Slow-breathing task, Six-minute exercise test, Indirect calorimetry, Oxygen saturation monitoring, heart rate variability analysis, continuous measurement of arterial blood pressure, lung function test, the Nijmegen Questionnaire and the Self-Evaluation of Breathing Questionnaire, the Hospital anxiety and depression scale, Asthma Control Questionnaire, and the Short-Form Survey Instrument, Breath-hold test, Lung function test, respiratory muscle function assessment.&#xD;
Days 2-8: Physical Activity Monitoring</description>
  </arm_group>
  <intervention>
    <intervention_type>Other</intervention_type>
    <intervention_name>Short-form survey instrument</intervention_name>
    <description>Questionnaire with questions about quality of life. Takes about 5 minutes to be completed.</description>
    <arm_group_label>Healthy participants</arm_group_label>
    <arm_group_label>Primary dysfunctional Breathing group</arm_group_label>
    <arm_group_label>Restrictive lung disease group</arm_group_label>
    <arm_group_label>Secondary dysfunctional breathing group</arm_group_label>
    <other_name>SF-36</other_name>
  </intervention>
  <intervention>
    <intervention_type>Other</intervention_type>
    <intervention_name>Demographic data</intervention_name>
    <description>height, weight, age, gender, list of comorbidities, health history, level of physical activity, medicines in use. Takes about 10 minutes to be completed.</description>
    <arm_group_label>Healthy participants</arm_group_label>
    <arm_group_label>Primary dysfunctional Breathing group</arm_group_label>
    <arm_group_label>Restrictive lung disease group</arm_group_label>
    <arm_group_label>Secondary dysfunctional breathing group</arm_group_label>
    <other_name>height, weight, age, gender</other_name>
  </intervention>
  <intervention>
    <intervention_type>Other</intervention_type>
    <intervention_name>Hospital Anxiety and Depression Scale</intervention_name>
    <description>Questionnaire with questions about anxiety and depression. Takes about 5 minutes to be completed.</description>
    <arm_group_label>Healthy participants</arm_group_label>
    <arm_group_label>Primary dysfunctional Breathing group</arm_group_label>
    <arm_group_label>Restrictive lung disease group</arm_group_label>
    <arm_group_label>Secondary dysfunctional breathing group</arm_group_label>
    <other_name>anxiety and depression questionnaire</other_name>
  </intervention>
  <intervention>
    <intervention_type>Other</intervention_type>
    <intervention_name>Nijmegen questionnaire</intervention_name>
    <description>Answering questions about symptoms related to breathing. Takes about 5 minutes to be completed.</description>
    <arm_group_label>Healthy participants</arm_group_label>
    <arm_group_label>Primary dysfunctional Breathing group</arm_group_label>
    <arm_group_label>Restrictive lung disease group</arm_group_label>
    <arm_group_label>Secondary dysfunctional breathing group</arm_group_label>
  </intervention>
  <intervention>
    <intervention_type>Other</intervention_type>
    <intervention_name>The Self-evaluation of breathing questionnaire</intervention_name>
    <description>Answering questions about self-evaluation of breathing. Takes about 5 minutes to be completed</description>
    <arm_group_label>Healthy participants</arm_group_label>
    <arm_group_label>Primary dysfunctional Breathing group</arm_group_label>
    <arm_group_label>Restrictive lung disease group</arm_group_label>
    <arm_group_label>Secondary dysfunctional breathing group</arm_group_label>
  </intervention>
  <intervention>
    <intervention_type>Other</intervention_type>
    <intervention_name>six-minute exercise test</intervention_name>
    <description>Cycling against certain load in a bicycle for 6 minutes. Takes about 16 minutes to be completed together with indirect calorimetry, oxygen saturation monitoring, heart rate variability analysis and continuous monitoring of arterial blood pressure).</description>
    <arm_group_label>Healthy participants</arm_group_label>
    <arm_group_label>Primary dysfunctional Breathing group</arm_group_label>
    <arm_group_label>Restrictive lung disease group</arm_group_label>
    <arm_group_label>Secondary dysfunctional breathing group</arm_group_label>
  </intervention>
  <intervention>
    <intervention_type>Other</intervention_type>
    <intervention_name>Indirect calorimetry</intervention_name>
    <description>Breathing through a mask that measures levels of oxygen, carbon dioxide, breathing frequency and others (non-invasively). Takes about 16 minutes to be completed, together with the 6-minute exercise test.</description>
    <arm_group_label>Healthy participants</arm_group_label>
    <arm_group_label>Primary dysfunctional Breathing group</arm_group_label>
    <arm_group_label>Restrictive lung disease group</arm_group_label>
    <arm_group_label>Secondary dysfunctional breathing group</arm_group_label>
    <other_name>gas analysis</other_name>
  </intervention>
  <intervention>
    <intervention_type>Other</intervention_type>
    <intervention_name>Oxygen saturation monitoring</intervention_name>
    <description>The measurement of the amount of oxygen which is attached to haemoglobin molecules (non-invasively). Takes about 16 minutes to be completed, together with the 6-minute exercise test.</description>
    <arm_group_label>Healthy participants</arm_group_label>
    <arm_group_label>Primary dysfunctional Breathing group</arm_group_label>
    <arm_group_label>Restrictive lung disease group</arm_group_label>
    <arm_group_label>Secondary dysfunctional breathing group</arm_group_label>
  </intervention>
  <intervention>
    <intervention_type>Other</intervention_type>
    <intervention_name>Heart rate variability analysis</intervention_name>
    <description>Measurement of the variation in the beat-to-beat interval (non-invasively). Takes about 16 minutes to be completed, together with the 6-minute exercise test.</description>
    <arm_group_label>Healthy participants</arm_group_label>
    <arm_group_label>Primary dysfunctional Breathing group</arm_group_label>
    <arm_group_label>Restrictive lung disease group</arm_group_label>
    <arm_group_label>Secondary dysfunctional breathing group</arm_group_label>
  </intervention>
  <intervention>
    <intervention_type>Other</intervention_type>
    <intervention_name>Continuous measurement of arterial blood pressure</intervention_name>
    <description>Measurement of blood pressure based on the peripheral pulse using a finger cuff (non-invasively). Takes about 16 minutes to be completed, together with the 6-minute exercise test.</description>
    <arm_group_label>Healthy participants</arm_group_label>
    <arm_group_label>Primary dysfunctional Breathing group</arm_group_label>
    <arm_group_label>Restrictive lung disease group</arm_group_label>
    <arm_group_label>Secondary dysfunctional breathing group</arm_group_label>
  </intervention>
  <intervention>
    <intervention_type>Diagnostic Test</intervention_type>
    <intervention_name>Lung function test</intervention_name>
    <description>Breathing through a mouth-piece in many different ways in order to measure the function of the lungs (non-invasively).</description>
    <arm_group_label>Healthy participants</arm_group_label>
    <arm_group_label>Primary dysfunctional Breathing group</arm_group_label>
    <arm_group_label>Restrictive lung disease group</arm_group_label>
    <arm_group_label>Secondary dysfunctional breathing group</arm_group_label>
  </intervention>
  <intervention>
    <intervention_type>Other</intervention_type>
    <intervention_name>Respiratory muscle function</intervention_name>
    <description>Breathing through a mouth-piece in many different ways in order to measure the function of the respiratory muscles (non-invasively).</description>
    <arm_group_label>Healthy participants</arm_group_label>
    <arm_group_label>Primary dysfunctional Breathing group</arm_group_label>
    <arm_group_label>Restrictive lung disease group</arm_group_label>
    <arm_group_label>Secondary dysfunctional breathing group</arm_group_label>
  </intervention>
  <intervention>
    <intervention_type>Other</intervention_type>
    <intervention_name>Manual assessment of respiratory motion</intervention_name>
    <description>Measure of the movements of the thorax while the participant is breathing (non-invasively).</description>
    <arm_group_label>Healthy participants</arm_group_label>
    <arm_group_label>Primary dysfunctional Breathing group</arm_group_label>
    <arm_group_label>Restrictive lung disease group</arm_group_label>
    <arm_group_label>Secondary dysfunctional breathing group</arm_group_label>
  </intervention>
  <intervention>
    <intervention_type>Other</intervention_type>
    <intervention_name>Breath-hold test</intervention_name>
    <description>Holding the breath a few times for as long as possible.</description>
    <arm_group_label>Healthy participants</arm_group_label>
    <arm_group_label>Primary dysfunctional Breathing group</arm_group_label>
    <arm_group_label>Restrictive lung disease group</arm_group_label>
    <arm_group_label>Secondary dysfunctional breathing group</arm_group_label>
  </intervention>
  <intervention>
    <intervention_type>Other</intervention_type>
    <intervention_name>Physical Activity monitoring</intervention_name>
    <description>Wearing a light-weight activity monitor to be wore on the hip for 7 consecutive days during, at least, 8 hours per day.</description>
    <arm_group_label>Healthy participants</arm_group_label>
    <arm_group_label>Primary dysfunctional Breathing group</arm_group_label>
    <arm_group_label>Restrictive lung disease group</arm_group_label>
    <arm_group_label>Secondary dysfunctional breathing group</arm_group_label>
  </intervention>
  <intervention>
    <intervention_type>Other</intervention_type>
    <intervention_name>Asthma Control Questionnaire</intervention_name>
    <description>Only for asthmatics: answering questions about the control the participant has over this respiratory condition/symptoms.</description>
    <arm_group_label>Secondary dysfunctional breathing group</arm_group_label>
  </intervention>
  <eligibility>
    <study_pop>
      <textblock>
        Patients with primary/secondary dysfunctional breathing and patients with restrictive lung&#xD;
        diseases will be recruited from clinics of respiratory medicine (secondary care). Healthy&#xD;
        participants will be recruited from the general population (at Brunel University London).&#xD;
      </textblock>
    </study_pop>
    <sampling_method>Non-Probability Sample</sampling_method>
    <criteria>
      <textblock>
        Inclusion Criteria:&#xD;
&#xD;
          -  patients with DB (according to the CD)&#xD;
&#xD;
          -  healthy people&#xD;
&#xD;
          -  aged 18 or over,&#xD;
&#xD;
          -  must be able to comprehend and/or perform the procedures of this research&#xD;
&#xD;
          -  must be able to consent to participate&#xD;
&#xD;
          -  people with signs of breathlessness secondary to restrictive lung disease (DB&#xD;
             excluded)&#xD;
&#xD;
        Exclusion Criteria:&#xD;
&#xD;
          -  people whose condition is unstable or have experienced an exacerbation of symptoms&#xD;
             over the last 4 weeks&#xD;
&#xD;
          -  patients who are oxygen-dependant (at rest or during exercise),&#xD;
&#xD;
          -  those who are on oral steroids or have completed a course of those medications less&#xD;
             than four weeks prior to the assessment day,&#xD;
&#xD;
          -  those who have major orthopaedic, neurological or cardiac conditions&#xD;
&#xD;
          -  those who received breathing retraining before&#xD;
      </textblock>
    </criteria>
    <gender>All</gender>
    <minimum_age>18 Years</minimum_age>
    <maximum_age>N/A</maximum_age>
    <healthy_volunteers>Accepts Healthy Volunteers</healthy_volunteers>
  </eligibility>
  <overall_official>
    <last_name>Panagiota Smyrni, Dr</last_name>
    <role>Study Chair</role>
    <affiliation>Brunel University London</affiliation>
  </overall_official>
  <overall_contact>
    <last_name>Lais S Vidotto, Ms</last_name>
    <phone>4401895278024</phone>
    <email>lais.vidotto@brunel.ac.uk</email>
  </overall_contact>
  <location>
    <facility>
      <name>Brunel University London</name>
      <address>
        <city>London</city>
        <state>Middlesex</state>
        <zip>UB83PH</zip>
        <country>United Kingdom</country>
      </address>
    </facility>
    <contact>
      <last_name>Lais S Vidotto, BSc MSc</last_name>
      <phone>+44 (0)1895 268985</phone>
      <email>lais.vidotto@brunel.ac.uk</email>
    </contact>
    <contact_backup>
      <last_name>Panagiota Smyrni, PhD</last_name>
      <phone>+44 (0)1895 268771</phone>
      <email>panagiota.smyrni@brunel.ac.uk</email>
    </contact_backup>
  </location>
  <location_countries>
    <country>United Kingdom</country>
  </location_countries>
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  <verification_date>July 2020</verification_date>
  <study_first_submitted>January 30, 2017</study_first_submitted>
  <study_first_submitted_qc>February 2, 2017</study_first_submitted_qc>
  <study_first_posted type="Estimate">February 6, 2017</study_first_posted>
  <last_update_submitted>July 7, 2020</last_update_submitted>
  <last_update_submitted_qc>July 7, 2020</last_update_submitted_qc>
  <last_update_posted type="Actual">July 8, 2020</last_update_posted>
  <responsible_party>
    <responsible_party_type>Principal Investigator</responsible_party_type>
    <investigator_affiliation>Brunel University</investigator_affiliation>
    <investigator_full_name>Lais Silva Vidotto</investigator_full_name>
    <investigator_title>Ms Lais Silva Vidotto</investigator_title>
  </responsible_party>
  <keyword>dysfunctional breathing</keyword>
  <condition_browse>
    <!-- CAUTION:  The following MeSH terms are assigned with an imperfect algorithm            -->
    <mesh_term>Dyspnea</mesh_term>
    <mesh_term>Hyperventilation</mesh_term>
    <mesh_term>Respiration Disorders</mesh_term>
  </condition_browse>
  <patient_data>
    <sharing_ipd>No</sharing_ipd>
  </patient_data>
  <!-- Results have not yet been posted for this study                                          -->
</clinical_study>


download date: ClinicalTrials.gov processed this data on September 20, 2023
link text: Link to the current ClinicalTrials.gov record.
url: https://clinicaltrials.gov/ct2/show/NCT03043469
org study id: 1468-NHS-Dec/2016- 4775-1
nct id: NCT03043469
lead sponsor: 
collaborator: 
has dmc: No
is fda regulated drug: No
is fda regulated device: No
Dysfunctional breathing (DB) is a respiratory condition characterised by an abnormal
      breathing pattern, among other complaints, that can occur either in the absence of other
      pathophysiology (primary DB), e.g. anxiety-related factors, or secondary to cardiopulmonary
      disease (secondary DB), e.g. asthma. As a consequence, patients may experience breathlessness
      and present with periods of increased ventilation or erratic breathing, interspersed with
      episodes of breath holding or deep sighs. In addition to respiratory symptoms, DB also
      generates non- respiratory symptoms (e.g. dizziness and increased heart rate). It is
      estimated 1 in 10 people in the United Kingdom (UK) have DB. However, DB remains poorly
      understood, with no standardised approach to diagnosis and assessment.

      The purposes of this study are:

      Study 1) To identify physiological, functional and psychological characteristics of
      participants with DB compared to healthy participants.

      Firstly, symptoms, lung function, respiratory gas analysis, exercise capacity, respiratory
      muscle function, respiratory motion, level of physical activity, quality of life and anxiety
      & depression scores will be assessed in 20 participants with primary DB, 20 with secondary DB
      and compared to 20 healthy participants.

      Study 2) To develop an assessment tool based on physiological, functional or psychological
      variables found to be different between any of the 3 groups in Study 1.

      In order to do that, 54 people with DB (between primary and secondary) and 27 people
      presenting with breathlessness secondary to restrictive lung disease will be assessed.
      Analysis of these data will determine whether these variables can be used as a diagnostic
      tool capable of distinguishing DB from restrictive lung diseases characterised by
      breathlessness.

      The recruitment period will be 1-2 years, with an individual participation of 9 days; 1-day
      on site testing, plus 7-day home activity monitoring, and 1 day to return the activity
      monitor (which will happen whenever the participant needs to return to the site).
In this research, the aims are: 1) to characterise and compare participants with primary
      dysfunctional breathing (DB), secondary DB and healthy participants, 2) to develop an
      assessment and identification tool for the population with DB, 3) to identify subgroups of
      people with DB based on their functional, physiological and psychological characteristics.

      In order to do that, in Study 1, there will be a comparison of many different aspects
      (described below) between three groups of 20 participants each: primary DB, secondary DB and
      healthy participants. With the results of these comparisons, it will be possible to know more
      about the differences people with DB have in relation to the healthy population, and to
      describe their main characteristics. Based on that, in Study 2, it will be possible to select
      the variables that are different between groups and replicate those tests in an extra 54
      participants DB (primary and secondary) and 27 with breathlessness secondary to restrictive
      lung disease (DB excluded). The second stage will suggest tests to be used when identifying
      and evaluating this population, and statistically identify subgroups of people with DB based
      on their characteristics.

      It is important to note why the inclusion of healthy participants and participants with
      breathlessness secondary to restrictive lung disease is important in this research programme.
      Firstly, it is essential to know the main characteristics of DB in relation to the healthy
      population. Secondly, the assessment tool has to be able to suggest probability of negative
      diagnosis of DB for people who do not have DB, and not only positive diagnosis for those who
      have.

      There are no standardised criteria available to diagnose DB. However, experienced chest
      physicians at Guy's and St Thomas' Foundation Trust (GSTFT) identify probable DB, and provide
      a clinical diagnosis (CD) according to the following criteria: patients presenting with
      symptoms that are not concordant with the severity of the underlying health condition (in
      case of secondary DB), patients presenting with symptoms that persist despite optimal disease
      management and/or no objective markers of deterioration/exacerbation (in case of secondary
      DB), patients presenting with symptoms in the presence of negative tests for organic
      cause/medically unexplained (in case of primary DB), patients presenting with symptoms that
      are considered functional (in case of primary DB).

      Ability to comprehend and/or perform the procedures of this research, as well as the presence
      of major orthopaedic, neurological or cardiac conditions will be checked by Leyla Osman and
      the Chest physicians via medical records and when the possible participant is approached to
      receive information about the study. For example: health conditions in which patients present
      with an impairment of mental faculties and/or motor function (inability to cycle with no
      discomfort).

      Healthy participants will be contacted via email list at Brunel University London, and via
      flyers placed on the University's and Hospital's website and murals (attached). Participants
      with restrictive lung disease will be reached in person or via telephone call when they are
      referred to respiratory physiotherapy, or via flyers placed on the Hospital's murals. Because
      there are not plenty of patients with DB, those who are already registered on the Hospital's
      system as presenting with DB (assessed by a chest physician) will be called. New patients
      with DB will be contacted in person or via telephone call by the respiratory physiotherapist
      of the clinical team (Leyla Osman).

      If those contacted about this research are interested in taking part in this study, they will
      be provided with the participant information sheet, have the opportunity to ask any questions
      they may have and it will be checked if they meet the inclusion criteria. Before starting the
      assessments, they will be asked to sign the informed consent.

      When signing the informed consent, participants will be asked a few questions:

      Please, tick this box if you authorise the researchers of this study to have access to your
      medical records Please, tick this box if you are aware that your General practitioner will be
      informed about your participation in this research Please, tick this box if you would like to
      receive a report with your results of the tests performed in this study (within 30 days from
      the end of your assessments) Please, tick this box if you would like us to contact you in the
      future to inform you about the final results of this study Please, tick this box if you are
      participating in other study/ies at this moment. If yes, please mention below what this/these
      study/ies is/are about and the contact of the person responsible for it The assessments will
      be performed by Lais Silva Vidotto (respiratory physiotherapist and researcher) at the
      Hospital/University over a period of approximately 3 hours. Many of these assessments form
      part of routine hospital investigations for patients with DB. Duration may vary depending on
      individual needs and limitations, such as time given to recover from any physical or mental
      effort. Secondly, a physical activity monitor will be given to all participants, which will
      be returned to the researchers on the next medical appointment at the Hospital/classes at the
      University (classes at the University in case of healthy participants). During the 3-hour
      assessment they will have the opportunity to rest whenever is necessary and snacks and
      refreshments will be provided in the intervals (caffeine-free ingredients).

      Assessments and their approximate duration are as follows: demographic information (10
      minutes), health-related quality of life questionnaire (SF-36) (5 minutes), Hospital anxiety
      and depression scale (HADS) (5 minutes), Nijmegen questionnaire (NQ) (5 minutes),
      Self-evaluation of breathing questionnaire (SEBQ) (5 minutes), Asthma Questionnaire (only for
      asthmatics) (5 minutes), lung function test (30 minutes), respiratory muscle function (30
      minutes, assessment of the respiratory movements (MARM) (10 minutes), breath-hold test (BHT)
      (20 minutes), slow-breathing task (15 minutes) and the sub-maximal exercise test (10 minutes)
      (during the two last tests participants will be wearing small and light-weight devices that
      monitor heart activity, breathing function and blood pressure and take 15 minutes to be
      placed all together).

      Day 1: Hospital assessments (~3 hours) The tests will be performed in a private room at St
      Thomas' Hospital or Brunel University London. Participants will be advised to stay 48 hours
      without practicing exercise. Also, they will be instructed to take all the medicines they
      normally use and to report their names and doses to the examiner.

        1. Patients will be asked about their medical history, date of birth and symptoms. Also,
           participants' weight and height will be measured.

        2. Chest movements while breathing:

           At this stage, participants are going to stand still while the researcher will place
           their hands on the back of their chests in order to evaluate its movements while
           participants are breathing. This is going to take about 10 minutes.

        3. Slow-breathing task:

           Participants will be instructed on how to breathe slower (6-10 bpm) for a few minutes
           (5-15 minutes) and will keep wearing the mask, the heart rate monitor and the arterial
           blood pressure monitor during this task.

        4. Exercise test, breathing and cardiovascular function:

           Light-weight devices will be attached to participants' chest (cardiac monitor), in order
           to evaluate heart function, to their faces (mask-gas analyser) to assess respiratory
           function, and to their non-dominant arm (arm and finger), to assess blood pressure. The
           device used to assess blood pressure continuously measures the pulse of the finger,
           calibrated by an arm cuff, with no discomfort to the participant. Those assessments will
           be performed while participants rest for five minutes, while they cycle on a bicycle
           with moderate resistance for six minutes, and while they rest for five more minutes.
           Just before the exercise test, at the third minute, and just after it, participants will
           be asked about any leg or breathing discomfort and how mindful they are in relation to
           discomfort related to the task. Approximate time of this task: 16 minutes.

        5. Questionnaires:

           Participants will be asked to fill in some questionnaires that will ask about their
           breathing and quality of life and will take about 25 minutes to complete. Participants
           will be asked to complete these questionnaires after having the opportunity to ask
           questions about them.

        6. Breath hold test:

           Participants will be asked to hold their breath for as long as they can for 3 times,
           resting for 5 minutes after each one of them, and the researcher will use a stopwatch in
           order to count the time they are able to do it. The whole task will last in
           approximately 20 minutes.

        7. Lung and respiratory muscle function assessments:

      Researchers will use three devices to measure the function of participants' lungs and
      respiratory muscles. They will be asked to breathe in and out in several different ways,
      wearing a nose clip, so that researchers can record their general breathing function. This is
      going to take about one hour to finish.

      At the end of the assessment session, participants will be instructed on how to use a device
      that measures the level of physical activity.

      Days 2-8: Physical Activity Monitoring Participants will be asked to wear two small activity
      monitors attached to their hip for 7 consecutive days, keeping their routine as normal as
      possible. Participants will have to use the equipment for at least 8 hours/day while they are
      awake, excluding water activities (e.g. shower) and sleeping, writing down the exact time
      they put it on and the time they took this off.

      Day 9: Return of the activity monitors Participants recruited from Brunel University London
      will return their physical activity monitors to the researchers on their next visit to the
      University (for classes, meetings etc.); those recruited from GSTFT will return it on their
      next hospital appointment.

      Although this study requires a cross-sectional design, it may take a long period to be
      completed, since patients with DB are not easily identified and referred to other health
      professionals to receive specific diagnosis or treatment. Considering this difficulty in
      finding participants with DB, justified by the fact that there is no established way of
      identifying these patients, this research may take 1-2 years to be completed. However, It
      will enable the researchers to look at every single result and be rigorous with the quality
      of the data collected. In order to do that, the researchers will not wait for all assessments
      to be finished to process and plot the data. Every time a participant is evaluated, their
      results will be organised and plotted within the next few days. It will also enable the data
      to be statistically analysed when needed.
observational model: Case-Control
time perspective: Cross-Sectional
measure: Signs of Anxiety and Depression
time frame: This scale will be applied only once during the first day of assessment and takes about 5 minutes for the participant to complete.
description: Anxiety and depression will be evaluated by the widely used Hospital Anxiety and Depression Scale (HADS), developed by Zigmond and Snaith (1983) to identify and screen cases of anxiety and depression in non-psychiatric environments. It has been proven to be a valid psychological instrument (Bjelland et al. 2002). The HADS is subdivided into two subscales with seven questions each: Anxiety (HADS-A) and Depression (HADS-B). Therefore, it is able to differentiate anxiety from depression possible/probable disorders.
measure: Levels of subjective sensation related to Hyperventilation Syndrome
time frame: This scale will be applied only once and takes about 5 minutes to be completed by the participant.
description: The Nijmegen Questionnaire is a clinically used tool for analysis of 16 symptoms related to Hyperventilation syndrome arising from different body systems (such as chest pain, blurred vision and faster or deeper breathing). The participant will choose the answer from a 5-point ordinal scale considering the frequency of symptoms. 23 of 64 points or more is considered positive for abnormality of subjective sensations (van Dixhoorn and Folgering 2015) and correlates positively with Dysfunctional Breathing (Vansteenkiste, Rochette, Demedt, 1991).
measure: Self-evaluation of breathing
time frame: This scale will be applied only once and takes about 5 minutes to be completed by the participant..
description: The Self Evaluation Breathing Questionnaire is a reliable tool developed by Courtney and Greenwood (2009) to assess breathing pattern of participants with Dysfunctional Breathing (Mitchell et al. 2015). It contains 17 items that are answered using a 4-point Likert scale and includes two main factors: "lack of air", which is about feeling and sensing; and "perception of inappropriate or restricted breathing", which is about observing or noticing. It has been indicated that the higher the SEBQ score, the more severe is the clinical condition of Dysfunctional Breathing (Mitchell et al. 2015). However, researchers who created the SEBQ questionnaire suggested that it can be used as a screening tool for identifying Dysfunctional Breathing and for monitoring changes in breathing symptoms after treatment, but there is no normal value available in the literature for this questionnaire yet (Courtney, Greenwood, et al. 2011).
measure: Respiratory Motion
time frame: This assessment will be applied only once and takes about 10 minutes to be completed.
description: The Manual Assessment of Respiratory Motion (MARM) will be used to assess thoracic and diaphragmatic movements during breathing and quantify their contribution as a percentage of the total breathing movement. During this evaluation, the examiner will position their open hands between posterior and lateral lower rib cage (lower four to six ribs) and the thumbs will vertically be positioned about 1 inch from the spine. In this position, it is possible for the examiner to identify lateral and vertical movements during breathing, as well as upper or lower rib cage predominance. The examiner will draw an upper, lower and horizontal lines starting from the centre of a circle, building a pie chart with the degree of expansion (Courtney et al. 2008, Courtney and van Dixhoorn 2014). A perfect balance between thoracic and abdominal motion during breathing presents a MARM between 0 and 6; as well as a value above 30 may be considered as dysfunctional (Courtney et al. 2011; Courtney et al. 2008).
measure: Breath-holding time
time frame: This assessment will be applied only once and takes about 20 minutes to be completed.
description: In the Breath-hold test, the variable considered is the total time the participant is able to hold a breath after a normal exhalation at functional residual capacity. This standardized protocol used in participants with DB is called the Buteyko Method of the Control Pause, where the breath is held and timed until the first involuntary motion of the respiratory muscles (Courtney and Cohen 2008). The breath-holding time has been estimated to be approximately 20 seconds patients with DB, while in healthy people is approximately 60 seconds (Jack et al. 2004, Courtney and Cohen 2008). Three attempts will be undertaken with 5-minute rest in between; a stopwatch will be used to time each one, as well as the intervals. The mean of the three attempts will be analysed, in order to remove any learnt effect (Courtney, Greenwood, et al. 2011).
measure: Medical History
time frame: This assessment will be applied during the 3-hour assessment, and takes about 5 minutes to be completed.
description: Participants will be asked about their medical history, health conditions, comorbidities, medicines in use and its doses.
measure: Age
time frame: This assessment will be applied during the 3-hour assessment, and takes about 20 seconds to be completed.
description: The date of birth (age) of the participants will be recorded and used for analyses.
measure: Gender
time frame: This assessment will be applied during the 3-hour assessment, and takes about 10 seconds to be completed.
description: The gender of the participants will be recorded and used for analyses.
measure: Weight
time frame: This assessment will be applied during the 3-hour assessment, and takes about 10 seconds to be completed.
description: The weight of the participants will be recorded based on self-report.
measure: Height
time frame: This assessment will be applied during the 3-hour assessment, and takes about 10 seconds to be completed.
description: The height of the participants will be recorded based on self-report.
measure: Body mass index (BMI)
time frame: The BMI will be calculated based on height and weight collected from the participants, and will take about 1 minute to be calculated.
description: The body mass index of the participants will be calculated as follows: weight over height squared.
measure: Level of physical activity
time frame: This assessment will be applied during the 3-hour assessment, and takes about 3 minutes to be completed.
description: The level of physical activity of the participants will be recorded based on self-report. They will be asked how many days of a typical week they participate in moderate-to-vigorous physical activity. Also, they will be asked how many minutes per day, during a typical week, they participate in moderate-to-vigorous physical activity. Finally, participants will be asked about any sports that they have participated in and at what level.
measure: Forced vital capacity (FVC)
time frame: This assessment will be applied during the 3-hour assessment, and takes about 10 minutes to be completed.
description: Lung function will be assessed by spirometry, as hypocapnia is associated with bronchoconstriction (Combes and Fauvage 1997, Brijker et al. 2001). Forced vital capacity (FVC) will be assessed following international recommendations (Miller et al. 2005) and the reference values will be calculated according to Quanjer et al. (1993) and Stanojevic et al. (2010). The participant will be instructed to exhale the maximum possible until residual volume and to inspire as rapid as possible, aiming a maximal and quick gasp until at least 50% of vital capacity.
measure: Forced expiratory volume in the first second (FEV1)
time frame: This assessment will be applied during the 3-hour assessment, and takes about 10 minutes to be completed.
description: Lung function will be assessed by spirometry, as hypocapnia is associated with bronchoconstriction (Combes and Fauvage 1997, Brijker et al. 2001). Forced expiratory volume in the first second (FEV1) will be assessed following international recommendations (Miller et al. 2005) and the reference values will be calculated according to Quanjer et al. (1993) and Stanojevic et al. (2010). The participant will be instructed to exhale the maximum possible until residual volume and to inspire as rapid as possible, aiming a maximal and quick gasp until at least 50% of vital capacity.
measure: Maximum voluntary ventilation (MVV)
time frame: This assessment will be applied during the 3-hour assessment, and takes about 10 minutes to be completed.
description: Lung function will be assessed by spirometry, as hypocapnia is associated with bronchoconstriction (Combes and Fauvage 1997, Brijker et al. 2001). Forced expiratory volume in the first second (FEV1) will be assessed following international recommendations (Miller et al. 2005) and the reference values will be calculated according to Quanjer et al. (1993) and Stanojevic et al. (2010). The participant will be instructed to ventilate with her or his maximal ventilation volume and frequency, inhaling and exhaling as deep and quick as possible.
measure: Peak inspiratory flow rate
time frame: This assessment will be applied during the 3-hour assessment, and takes about 10 minutes to be completed (together with the FVC, since this outcome is provided by the same manoeuvre).
description: The peak inspiratory flow rate will be measured based on the protocol described by McConnell (McConnell 2013). The participant will be instructed to exhale the maximum possible until residual volume and to inspire as rapid as possible, aiming a maximal and quick gasp until at least 50% of vital capacity.
measure: Peak expiratory flow rate
time frame: This assessment will be applied during the 3-hour assessment, and takes about 10 minutes to be completed.
description: The peak expiratory flow rate will be measured based on the protocol described by McConnell (McConnell 2013). The participant will be instructed to inhale the maximum possible until total vital capacity and to expire as rapid as possible, aiming a maximal and quick manoeuvre.
measure: Inspiratory muscle function
time frame: This assessment will be applied during the 3-hour assessment, and takes about 30 minutes to be completed.
description: Inspiratory muscle strength will be assessed by the maximal inspiratory pressure (MIP) measurement (McConnell and Copestake 1999, Volianitis et al. 2001) using a mouth pressure meter (Micro Medical RPM, Carefusion, San Diego, United States). The protocol to assess inspiratory muscle strength will be the one described by Black and Hyatt (1969), in which MIP is measured starting at residual volume (McConnell 2013). During the manoeuvre the participants will be instructed to sustain a maximal effort for at least 1.5-2.0 seconds, and a minimum of 5 satisfactory efforts will be considered according to Volianitis et al. (2001).
measure: Expiratory muscle function
time frame: This assessment will be applied during the 3-hour assessment, and takes about 30 minutes to be completed.
description: Expiratory muscle strength will be assessed by the maximal expiratory pressure (MEP) measurement (McConnell and Copestake 1999, Volianitis et al. 2001) using a mouth pressure meter (Micro Medical RPM, Carefusion, San Diego, United States). The protocol to assess expiratory muscle strength will be the one described by Black and Hyatt (1969), in which MEP is measured starting at total lung capacity (McConnell 2013). During the manoeuvre the participants will be instructed to sustain a maximal effort for at least 1.5-2.0 seconds, and a minimum of 5 satisfactory efforts will be considered according to Volianitis et al. (2001).
measure: Exercise capacity
time frame: This assessment will be applied during the 3-hour assessment, and takes about 16 minutes to be completed (simultaneously with the levels of heart rate variability, arterial blood pressure and gas exchange).
description: The Astrand-Ryhming submaximal test (Astrand and Ryhming 1954) will be used to assess exercise capacity of all participants and to predict maximal oxygen uptake. Participants will be instructed to stay 48 hours previous to the test without practicing exercise. This test will be performed on a cycle ergometer and power outputs of 75 to 150 watts and 100 to 200 watts will be used for women and men, respectively. The rotation of 50 rpm needs to be kept for 6 minutes. The HR is registered at the 5th and 6th minutes of the exercise test, and with the right load, these values cannot differentiate from each other more than 5 bpm. After that, a mathematic model will be used to predict the maximal oxygen uptake (Astrand and Ryhming 1954, Legge and Banister 1986, Macsween 2001).
measure: Level of heart rate variability
time frame: This assessment will be applied during the 3-hour assessment, and takes about 15 minutes to be placed and will be continuously used during the exercise test (16 minutes) and the slow-breathing task (15 minutes).
description: The heart rate variability (HRV) will be continuously assessed during five minutes before, during, and five minutes after the exercise test and during a controlled breathing of approximately 6-10 breaths per minute. HRV will be assessed by using a Polar® V800 device (Polar, Kempele-Finland), and the heart's electrical signal will be processed by using Kubios HRV version 2.2. The data will be initially filtered and smoothed to obtain heart rate frequency mean, time-domain analyses of the R-R intervals (interval between 2 "R" curves in the electrocardiogram (e.g., standard deviation of normal-to-normal RR intervals [SDNN] and root mean square of successive differences [RMSSD]) and spectral analyses of frequency indices (i.e., very low-frequency [0-0.04], low-frequency [0.04-0.15 Hz] and high-frequency [0.15-0.4 Hz]) aiming the further understanding of the autonomic nervous system responses in DB.
measure: Level of arterial blood pressure
time frame: This assessment will be applied during the 3-hour assessment, and takes about 15 minutes to be placed and will be continuously used during the exercise test (16 minutes) and the slow-breathing task (15 minutes).
description: The arterial blood pressure (ABP) will be continuously assessed during five minutes before, during, and five minutes after the exercise test and during a controlled breathing of approximately 6-10 breaths per minute. Finger ABP will be measured by the use of Finometer 1.10 (Finapres Medical System, Amsterdam - The Netherlands), which non-invasively registers continuous blood pressure measurements. The finger pressure generates a waveform and the ABP is exported based on calculations built every heartbeat (Bogert and van Lieshout 2005). Finger ABP signals will be processed by using the Lab Chart Pro Software, which records, displays and analyses real time data from up to 32 channels.
measure: Minute volume
time frame: This assessment will be applied during the 3-hour assessment, and takes about 15 minutes to be placed and will be continuously used during the exercise test (16 minutes) and the slow-breathing task (15 minutes).
description: The indirect calorimetry (IC) will be performed by the portable system K5® (Cosmed, Rome, Italy). This ergospirometer calculates breath-by-breath oscillations of minute volume (VE). The device will be attached to the participant's chest and a facemask, which has less than 30 ml of dead space, suitably adjusted to eliminate air leakage. The equipment will be programmed to assess data breath-by-breath and an average will be recorded every 5 seconds. Oxycon Pro software will be used to process the data for further analyses.
measure: Oxygen Uptake
time frame: This assessment will be applied during the 3-hour assessment, and takes about 15 minutes to be placed and will be continuously used during the exercise test (16 minutes) and the slow-breathing task (15 minutes).
description: The indirect calorimetry (IC) will be performed by the portable system K5® (Cosmed, Rome, Italy). This ergospirometer calculates breath-by-breath oscillations of oxygen uptake (O2). The device will be attached to the participant's chest and a facemask, which has less than 30 ml of dead space, suitably adjusted to eliminate air leakage. The equipment will be programmed to assess data breath-by-breath and an average will be recorded every 5 seconds. Oxycon Pro software will be used to process the data for further analyses.
measure: Carbon dioxide
time frame: This assessment will be applied during the 3-hour assessment, and takes about 15 minutes to be placed and will be continuously used during the exercise test (16 minutes) and the slow-breathing task (15 minutes).
description: The indirect calorimetry (IC) will be performed by the portable system K5® (Cosmed, Rome, Italy). This ergospirometer calculates breath-by-breath oscillations of carbon dioxide (CO2). The device will be attached to the participant's chest and a facemask, which has less than 30 ml of dead space, suitably adjusted to eliminate air leakage. The equipment will be programmed to assess data breath-by-breath and an average will be recorded every 5 seconds. Oxycon Pro software will be used to process the data for further analyses.
measure: Respiratory exchange ratio
time frame: This assessment will be applied during the 3-hour assessment, and takes about 15 minutes to be placed and will be continuously used during the exercise test (16 minutes) and the slow-breathing task (15 minutes).
description: The indirect calorimetry (IC) will be performed by the portable system K5® (Cosmed, Rome, Italy). This ergospirometer calculates breath-by-breath oscillations of respiratory exchange ratio (RER). The device will be attached to the participant's chest and a facemask, which has less than 30 ml of dead space, suitably adjusted to eliminate air leakage. The equipment will be programmed to assess data breath-by-breath and an average will be recorded every 5 seconds. Oxycon Pro software will be used to process the data for further analyses.
measure: Respiratory rate
time frame: This assessment will be applied during the 3-hour assessment, and takes about 15 minutes to be placed and will be continuously used during the exercise test (16 minutes) and the slow-breathing task (15 minutes).
description: The indirect calorimetry (IC) will be performed by the portable system K5® (Cosmed, Rome, Italy). This ergospirometer calculates breath-by-breath oscillations of respiratory rate (breaths per minute - BPM). The device will be attached to the participant's chest and a facemask, which has less than 30 ml of dead space, suitably adjusted to eliminate air leakage. The equipment will be programmed to assess data breath-by-breath and an average will be recorded every 5 seconds. Oxycon Pro software will be used to process the data for further analyses.
measure: Attentional focus
time frame: This assessment will be applied 3 times during the exercise test, and takes about 30 seconds to be completed each time. So, it will take approximately 1 minute and 30 seconds to be applied in total.
description: Attentional focus (Attention Scale [AS]; Tammen 1996, Tenenbaum et al. 2007) will be measured at various time points (pre exercise, at the 3rd minute, and at the end of the exercise test) during the execution of the six-minute cycling test described above.
measure: Level of fatigue
time frame: This assessment will be applied 3 times during the exercise test, and takes about 15 seconds to be completed each time. So, it will take approximately 45 seconds to be applied in total.
description: Limb discomfort (Category Ratio 10 [CR10-fatigue]; Borg 1982) (Borg Scale fatigue) will be measured at various time points (pre exercise, at the 3rd minute, and at the end of the exercise test) during the execution of the six-minute cycling test described above.
measure: Level of dyspnoea
time frame: This assessment will be applied 3 times during the exercise test, and takes about 15 seconds to be completed each time. So, it will take approximately 45 seconds to be applied in total.
description: Dyspnoea (CR10-dyspnoea; Borg 1982) (Borg Scale dyspnoea) will be measured at various time points (pre exercise, at the 3rd minute, and at the end of the exercise test) during the execution of the six-minute cycling test described above.
arm group label: Healthy participants
description: Day 1: Hospital assessments (~3 hours): Demographic data, Manual Assessment of Respiratory Motion, Slow-breathing task, Six-minute exercise test, Indirect calorimetry, Oxygen saturation monitoring, heart rate variability analysis, continuous measurement of arterial blood pressure, lung function test, the Nijmegen Questionnaire and the Self-Evaluation of Breathing Questionnaire, the Hospital anxiety and depression scale, and the Short-Form Survey Instrument, Breath-hold test, Lung function test, respiratory muscle function assessment.
Days 2-8: Physical Activity Monitoring
arm group label: Restrictive lung disease group
description: Day 1: Hospital assessments (~3 hours): Demographic data, Manual Assessment of Respiratory Motion, Slow-breathing task, Six-minute exercise test, Indirect calorimetry, Oxygen saturation monitoring, heart rate variability analysis, continuous measurement of arterial blood pressure, lung function test, the Nijmegen Questionnaire and the Self-Evaluation of Breathing Questionnaire, the Hospital anxiety and depression scale, and the Short-Form Survey Instrument, Breath-hold test, Lung function test, respiratory muscle function assessment.
Days 2-8: Physical Activity Monitoring
arm group label: Primary dysfunctional Breathing group
description: Day 1: Hospital assessments (~3 hours): Demographic data, Manual Assessment of Respiratory Motion, Slow-breathing task, Six-minute exercise test, Indirect calorimetry, Oxygen saturation monitoring, heart rate variability analysis, continuous measurement of arterial blood pressure, lung function test, the Nijmegen Questionnaire and the Self-Evaluation of Breathing Questionnaire, the Hospital anxiety and depression scale, and the Short-Form Survey Instrument, Breath-hold test, Lung function test, respiratory muscle function assessment.
Days 2-8: Physical Activity Monitoring
arm group label: Secondary dysfunctional breathing group
description: Day 1: Hospital assessments (~3 hours): Demographic data, Manual Assessment of Respiratory Motion, Slow-breathing task, Six-minute exercise test, Indirect calorimetry, Oxygen saturation monitoring, heart rate variability analysis, continuous measurement of arterial blood pressure, lung function test, the Nijmegen Questionnaire and the Self-Evaluation of Breathing Questionnaire, the Hospital anxiety and depression scale, Asthma Control Questionnaire, and the Short-Form Survey Instrument, Breath-hold test, Lung function test, respiratory muscle function assessment.
Days 2-8: Physical Activity Monitoring
intervention type: Other
intervention name: Short-form survey instrument
description: Questionnaire with questions about quality of life. Takes about 5 minutes to be completed.
arm group label: Healthy participants
arm group label: Primary dysfunctional Breathing group
arm group label: Restrictive lung disease group
arm group label: Secondary dysfunctional breathing group
other name: SF-36
intervention type: Other
intervention name: Demographic data
description: height, weight, age, gender, list of comorbidities, health history, level of physical activity, medicines in use. Takes about 10 minutes to be completed.
arm group label: Healthy participants
arm group label: Primary dysfunctional Breathing group
arm group label: Restrictive lung disease group
arm group label: Secondary dysfunctional breathing group
other name: height, weight, age, gender
intervention type: Other
intervention name: Hospital Anxiety and Depression Scale
description: Questionnaire with questions about anxiety and depression. Takes about 5 minutes to be completed.
arm group label: Healthy participants
arm group label: Primary dysfunctional Breathing group
arm group label: Restrictive lung disease group
arm group label: Secondary dysfunctional breathing group
other name: anxiety and depression questionnaire
intervention type: Other
intervention name: Nijmegen questionnaire
description: Answering questions about symptoms related to breathing. Takes about 5 minutes to be completed.
arm group label: Healthy participants
arm group label: Primary dysfunctional Breathing group
arm group label: Restrictive lung disease group
arm group label: Secondary dysfunctional breathing group
intervention type: Other
intervention name: The Self-evaluation of breathing questionnaire
description: Answering questions about self-evaluation of breathing. Takes about 5 minutes to be completed
arm group label: Healthy participants
arm group label: Primary dysfunctional Breathing group
arm group label: Restrictive lung disease group
arm group label: Secondary dysfunctional breathing group
intervention type: Other
intervention name: six-minute exercise test
description: Cycling against certain load in a bicycle for 6 minutes. Takes about 16 minutes to be completed together with indirect calorimetry, oxygen saturation monitoring, heart rate variability analysis and continuous monitoring of arterial blood pressure).
arm group label: Healthy participants
arm group label: Primary dysfunctional Breathing group
arm group label: Restrictive lung disease group
arm group label: Secondary dysfunctional breathing group
intervention type: Other
intervention name: Indirect calorimetry
description: Breathing through a mask that measures levels of oxygen, carbon dioxide, breathing frequency and others (non-invasively). Takes about 16 minutes to be completed, together with the 6-minute exercise test.
arm group label: Healthy participants
arm group label: Primary dysfunctional Breathing group
arm group label: Restrictive lung disease group
arm group label: Secondary dysfunctional breathing group
other name: gas analysis
intervention type: Other
intervention name: Oxygen saturation monitoring
description: The measurement of the amount of oxygen which is attached to haemoglobin molecules (non-invasively). Takes about 16 minutes to be completed, together with the 6-minute exercise test.
arm group label: Healthy participants
arm group label: Primary dysfunctional Breathing group
arm group label: Restrictive lung disease group
arm group label: Secondary dysfunctional breathing group
intervention type: Other
intervention name: Heart rate variability analysis
description: Measurement of the variation in the beat-to-beat interval (non-invasively). Takes about 16 minutes to be completed, together with the 6-minute exercise test.
arm group label: Healthy participants
arm group label: Primary dysfunctional Breathing group
arm group label: Restrictive lung disease group
arm group label: Secondary dysfunctional breathing group
intervention type: Other
intervention name: Continuous measurement of arterial blood pressure
description: Measurement of blood pressure based on the peripheral pulse using a finger cuff (non-invasively). Takes about 16 minutes to be completed, together with the 6-minute exercise test.
arm group label: Healthy participants
arm group label: Primary dysfunctional Breathing group
arm group label: Restrictive lung disease group
arm group label: Secondary dysfunctional breathing group
intervention type: Diagnostic Test
intervention name: Lung function test
description: Breathing through a mouth-piece in many different ways in order to measure the function of the lungs (non-invasively).
arm group label: Healthy participants
arm group label: Primary dysfunctional Breathing group
arm group label: Restrictive lung disease group
arm group label: Secondary dysfunctional breathing group
intervention type: Other
intervention name: Respiratory muscle function
description: Breathing through a mouth-piece in many different ways in order to measure the function of the respiratory muscles (non-invasively).
arm group label: Healthy participants
arm group label: Primary dysfunctional Breathing group
arm group label: Restrictive lung disease group
arm group label: Secondary dysfunctional breathing group
intervention type: Other
intervention name: Manual assessment of respiratory motion
description: Measure of the movements of the thorax while the participant is breathing (non-invasively).
arm group label: Healthy participants
arm group label: Primary dysfunctional Breathing group
arm group label: Restrictive lung disease group
arm group label: Secondary dysfunctional breathing group
intervention type: Other
intervention name: Breath-hold test
description: Holding the breath a few times for as long as possible.
arm group label: Healthy participants
arm group label: Primary dysfunctional Breathing group
arm group label: Restrictive lung disease group
arm group label: Secondary dysfunctional breathing group
intervention type: Other
intervention name: Physical Activity monitoring
description: Wearing a light-weight activity monitor to be wore on the hip for 7 consecutive days during, at least, 8 hours per day.
arm group label: Healthy participants
arm group label: Primary dysfunctional Breathing group
arm group label: Restrictive lung disease group
arm group label: Secondary dysfunctional breathing group
intervention type: Other
intervention name: Asthma Control Questionnaire
description: Only for asthmatics: answering questions about the control the participant has over this respiratory condition/symptoms.
arm group label: Secondary dysfunctional breathing group
study pop: 
sampling method: Non-Probability Sample
criteria: 
gender: All
minimum age: 18 Years
maximum age: N/A
healthy volunteers: Accepts Healthy Volunteers
last name: Panagiota Smyrni, Dr
role: Study Chair
affiliation: Brunel University London
last name: Lais S Vidotto, Ms
phone: 4401895278024
email: lais.vidotto@brunel.ac.uk
facility: 
contact: 
contact backup: 
country: United Kingdom
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responsible party type: Principal Investigator
investigator affiliation: Brunel University
investigator full name: Lais Silva Vidotto
investigator title: Ms Lais Silva Vidotto
mesh term: Dyspnea
mesh term: Hyperventilation
mesh term: Respiration Disorders
sharing ipd: No