<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/NCT01704300</url>
  </required_header>
  <id_info>
    <org_study_id>CALIBER 10_14</org_study_id>
    <nct_id>NCT01704300</nct_id>
  </id_info>
  <brief_title>Body Mass Index and Initial Presentations of Cardiovascular Diseases</brief_title>
  <acronym>CALIBER</acronym>
  <official_title>Body Mass Index and Initial Presentations of Cardiovascular Diseases</official_title>
  <sponsors>
    <lead_sponsor>
      <agency>University College, London</agency>
      <agency_class>Other</agency_class>
    </lead_sponsor>
  </sponsors>
  <source>University College, London</source>
  <oversight_info>
    <has_dmc>Yes</has_dmc>
  </oversight_info>
  <brief_summary>
    <textblock>
      The association between obesity and cardiovascular disease (CVD) has mostly been studied&#xD;
      using broad endpoints or have focused on cause-specific mortality. The investigators aim to&#xD;
      compare the effect of body mass index (BMI) on different types of initial presentation of&#xD;
      CVD.&#xD;
    </textblock>
  </brief_summary>
  <detailed_description>
    <textblock>
      Obesity has many detrimental effects on the cardiovascular system that can manifest in a&#xD;
      range of clinical presentations. Many of these are mediated by frequently coexisting&#xD;
      conditions such as diabetes, hypertension and dyslipidemia but there are also direct,&#xD;
      progressive effects on the arteries and the heart muscle. As evident from autopsies, even&#xD;
      from early adulthood the degree of coronary artery disease (CAD) correlates with the BMI and&#xD;
      particularly the amount of abdominal fat. The multiple mechanisms by which obesity exerts its&#xD;
      effects are still being elucidated.&#xD;
&#xD;
      Previous studies have assessed the effect of obesity on cause-specific mortality. Here the&#xD;
      investigators analyze association of BMI with the first symptomatic presentation of&#xD;
      cardiovascular disease across any phenotypes, to which the investigators refer to as &quot;initial&#xD;
      presentation&quot; to distinguish from first presentation within a specific phenotype. For&#xD;
      example, an initial presentation with myocardial infarction is an MI which is not preceded by&#xD;
      stable angina, ischemic stroke or any other phenotype, rather than the first MI in a possible&#xD;
      series of MIs, as is commonly used in other studies.&#xD;
&#xD;
      Adjustments The key risk factor of interest is baseline BMI, which the investigators define&#xD;
      as the most recent measurement of BMI recorded up to 2 years prior to cohort entry date. BMI&#xD;
      will be analyzed based on the following categories: underweight (&lt;18.5 kg/m2), healthy (18.5&#xD;
      to 24 kg/m2), overweight (25 to 29 kg/m2), moderately obese (30 to 34 kg/m2), morbidly obese&#xD;
      (&gt;35 kg/m2). The healthy BMI category will be used as the reference in regression models.&#xD;
&#xD;
      Associations with BMI will be adjusted for age, sex, ethnicity, social deprivation, smoking,&#xD;
      diabetes, and systolic blood pressure, total cholesterol (TCHOL) and high-density lipoprotein&#xD;
      cholesterol (HDL). All baseline covariates will be obtained from within a 2 year window prior&#xD;
      to study entry.&#xD;
&#xD;
      Statistical analyses Cause-specific Cox models will be used to measure the association&#xD;
      between BMI categories and endpoints of interest. Multiple imputation will be used to replace&#xD;
      missing values in prognostic factors. The investigators will estimate lifetime risk for each&#xD;
      endpoint over time adjusting for competing risks.&#xD;
    </textblock>
  </detailed_description>
  <overall_status>Completed</overall_status>
  <start_date>January 2001</start_date>
  <completion_date type="Actual">March 2010</completion_date>
  <primary_completion_date type="Actual">March 2010</primary_completion_date>
  <study_type>Observational</study_type>
  <has_expanded_access>No</has_expanded_access>
  <study_design_info>
    <observational_model>Cohort</observational_model>
    <time_perspective>Retrospective</time_perspective>
  </study_design_info>
  <number_of_groups>1</number_of_groups>
  <enrollment type="Actual">2240000</enrollment>
  <condition>Abdominal Aortic Aneurysm</condition>
  <condition>Acute Myocardial Infarction</condition>
  <condition>Stroke</condition>
  <condition>Heart Failure</condition>
  <condition>Peripheral Arterial Disease</condition>
  <condition>Angina</condition>
  <arm_group>
    <arm_group_label>CALIBER Healthy Cohort</arm_group_label>
    <description>We will report findings from the CALIBER (CArdiovascular disease research using Linked BEspoke studies and Electronic Records) collaboration where we linked primary care data (from the General Practice Research Database [GPRD]) to three further sources of electronic health records: the Myocardial Ischemia National Audit Project registry (MINAP),cause specific discharge data from Hospital Episodes Statistics (HES) and cause specific mortality from the Office for National Statistics (ONS).</description>
  </arm_group>
  <eligibility>
    <study_pop>
      <textblock>
        The cohort we will use in the present analysis has been drawn from patients across 225&#xD;
        practices in England contributing data to GPRD, covering approximately 5% of the UK&#xD;
        population (Figure 1). The study period is 1st January 2001 to 25th March 2010 (the date of&#xD;
        the last GPRD data submission). To allow time for medical history and risk factors to be&#xD;
        measured and recorded we require that patients enter the cohort after having completed at&#xD;
        least 1 year of registration with their current practice during which the practice provides&#xD;
        data that meet research quality criteria. Patients are followed up from the date they&#xD;
        become eligible to be included in the cohort until the earliest date among a) the date of&#xD;
        an initial presentation with one of the endpoints of interest, b) the date of leaving the&#xD;
        practice or c) the date of last data submission from their practice.&#xD;
      </textblock>
    </study_pop>
    <sampling_method>Non-Probability Sample</sampling_method>
    <criteria>
      <textblock>
        Inclusion Criteria:&#xD;
&#xD;
          -  Baseline age ≥30 years&#xD;
&#xD;
        Exclusion Criteria:&#xD;
&#xD;
          -  prior atherosclerotic disease or stroke&#xD;
      </textblock>
    </criteria>
    <gender>All</gender>
    <minimum_age>30 Years</minimum_age>
    <maximum_age>N/A</maximum_age>
    <healthy_volunteers>Accepts Healthy Volunteers</healthy_volunteers>
  </eligibility>
  <location>
    <facility>
      <name>University College London</name>
      <address>
        <city>London</city>
        <zip>WC1E 6BT</zip>
        <country>United Kingdom</country>
      </address>
    </facility>
  </location>
  <location_countries>
    <country>United Kingdom</country>
  </location_countries>
  <verification_date>October 2012</verification_date>
  <study_first_submitted>October 8, 2012</study_first_submitted>
  <study_first_submitted_qc>October 10, 2012</study_first_submitted_qc>
  <study_first_posted type="Estimate">October 11, 2012</study_first_posted>
  <last_update_submitted>October 10, 2012</last_update_submitted>
  <last_update_submitted_qc>October 10, 2012</last_update_submitted_qc>
  <last_update_posted type="Estimate">October 11, 2012</last_update_posted>
  <responsible_party>
    <responsible_party_type>Principal Investigator</responsible_party_type>
    <investigator_affiliation>University College, London</investigator_affiliation>
    <investigator_full_name>Harry Hemingway</investigator_full_name>
    <investigator_title>Harry Hemingway, FRCP</investigator_title>
  </responsible_party>
  <keyword>Abdominal aortic aneurysm</keyword>
  <keyword>Acute Myocardial Infarction</keyword>
  <keyword>Coronary heart disease not otherwise specified</keyword>
  <keyword>Haemorrhagic stroke</keyword>
  <keyword>Heart failure</keyword>
  <keyword>Ischaemic stroke</keyword>
  <keyword>Peripheral arterial disease</keyword>
  <keyword>Stable angina</keyword>
  <keyword>Unheralded coronary death</keyword>
  <keyword>Unstable angina</keyword>
  <keyword>Ventricular arrhythmias, cardiac arrest and sudden cardiac death</keyword>
  <keyword>Transient Ischemic Attack</keyword>
  <condition_browse>
    <!-- CAUTION:  The following MeSH terms are assigned with an imperfect algorithm            -->
    <mesh_term>Heart Failure</mesh_term>
    <mesh_term>Cardiovascular Diseases</mesh_term>
    <mesh_term>Myocardial Infarction</mesh_term>
    <mesh_term>Aneurysm</mesh_term>
    <mesh_term>Aortic Aneurysm</mesh_term>
    <mesh_term>Peripheral Arterial Disease</mesh_term>
    <mesh_term>Peripheral Vascular Diseases</mesh_term>
    <mesh_term>Aortic Aneurysm, Abdominal</mesh_term>
    <mesh_term>Infarction</mesh_term>
  </condition_browse>
  <!-- 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/NCT01704300
org study id: CALIBER 10_14
nct id: NCT01704300
lead sponsor: 
has dmc: Yes
The association between obesity and cardiovascular disease (CVD) has mostly been studied
      using broad endpoints or have focused on cause-specific mortality. The investigators aim to
      compare the effect of body mass index (BMI) on different types of initial presentation of
      CVD.
Obesity has many detrimental effects on the cardiovascular system that can manifest in a
      range of clinical presentations. Many of these are mediated by frequently coexisting
      conditions such as diabetes, hypertension and dyslipidemia but there are also direct,
      progressive effects on the arteries and the heart muscle. As evident from autopsies, even
      from early adulthood the degree of coronary artery disease (CAD) correlates with the BMI and
      particularly the amount of abdominal fat. The multiple mechanisms by which obesity exerts its
      effects are still being elucidated.

      Previous studies have assessed the effect of obesity on cause-specific mortality. Here the
      investigators analyze association of BMI with the first symptomatic presentation of
      cardiovascular disease across any phenotypes, to which the investigators refer to as "initial
      presentation" to distinguish from first presentation within a specific phenotype. For
      example, an initial presentation with myocardial infarction is an MI which is not preceded by
      stable angina, ischemic stroke or any other phenotype, rather than the first MI in a possible
      series of MIs, as is commonly used in other studies.

      Adjustments The key risk factor of interest is baseline BMI, which the investigators define
      as the most recent measurement of BMI recorded up to 2 years prior to cohort entry date. BMI
      will be analyzed based on the following categories: underweight (<18.5 kg/m2), healthy (18.5
      to 24 kg/m2), overweight (25 to 29 kg/m2), moderately obese (30 to 34 kg/m2), morbidly obese
      (>35 kg/m2). The healthy BMI category will be used as the reference in regression models.

      Associations with BMI will be adjusted for age, sex, ethnicity, social deprivation, smoking,
      diabetes, and systolic blood pressure, total cholesterol (TCHOL) and high-density lipoprotein
      cholesterol (HDL). All baseline covariates will be obtained from within a 2 year window prior
      to study entry.

      Statistical analyses Cause-specific Cox models will be used to measure the association
      between BMI categories and endpoints of interest. Multiple imputation will be used to replace
      missing values in prognostic factors. The investigators will estimate lifetime risk for each
      endpoint over time adjusting for competing risks.
observational model: Cohort
time perspective: Retrospective
arm group label: CALIBER Healthy Cohort
description: We will report findings from the CALIBER (CArdiovascular disease research using Linked BEspoke studies and Electronic Records) collaboration where we linked primary care data (from the General Practice Research Database [GPRD]) to three further sources of electronic health records: the Myocardial Ischemia National Audit Project registry (MINAP),cause specific discharge data from Hospital Episodes Statistics (HES) and cause specific mortality from the Office for National Statistics (ONS).
study pop: 
sampling method: Non-Probability Sample
criteria: 
gender: All
minimum age: 30 Years
maximum age: N/A
healthy volunteers: Accepts Healthy Volunteers
facility: 
country: United Kingdom
responsible party type: Principal Investigator
investigator affiliation: University College, London
investigator full name: Harry Hemingway
investigator title: Harry Hemingway, FRCP
mesh term: Heart Failure
mesh term: Cardiovascular Diseases
mesh term: Myocardial Infarction
mesh term: Aneurysm
mesh term: Aortic Aneurysm
mesh term: Peripheral Arterial Disease
mesh term: Peripheral Vascular Diseases
mesh term: Aortic Aneurysm, Abdominal
mesh term: Infarction