<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/NCT03304041</url>
  </required_header>
  <id_info>
    <org_study_id>20170116-2</org_study_id>
    <nct_id>NCT03304041</nct_id>
  </id_info>
  <brief_title>Efficacy of Low-FODMAPs Dietary Therapy for Irritable Bowel Syndrome in China</brief_title>
  <official_title>Efficacy of Low-FODMAPs Dietary Therapy Versus Traditional Dietary Advice for Diarrhea-predominant Irritable Bowel Syndrome in China - A Prospective Randomized Controlled Trial</official_title>
  <sponsors>
    <lead_sponsor>
      <agency>Sir Run Run Shaw Hospital</agency>
      <agency_class>Other</agency_class>
    </lead_sponsor>
    <collaborator>
      <agency>Zhejiang Academy of Agricultural Sciences</agency>
      <agency_class>Other</agency_class>
    </collaborator>
    <collaborator>
      <agency>University of Michigan</agency>
      <agency_class>Other</agency_class>
    </collaborator>
    <collaborator>
      <agency>Klinik Arlesheim</agency>
      <agency_class>Other</agency_class>
    </collaborator>
  </sponsors>
  <source>Sir Run Run Shaw Hospital</source>
  <oversight_info>
    <has_dmc>Yes</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>
      The primary aim of our study is to carry out a randomized trial to evaluate the efficacy of&#xD;
      low-FODMAPs dietary therapy compared to conventional therapy for IBS patients recruited from&#xD;
      tertiary hospitals in China. Secondary aims of this research include an analysis of clinical,&#xD;
      physiological and microbiological factors that may predict IBS patient response to this&#xD;
      dietary intervention.&#xD;
    </textblock>
  </brief_summary>
  <detailed_description>
    <textblock>
      Visit 1：Enrollment &amp; Screening &amp; Run-in period Patients who meet the inclusion criteria will&#xD;
      be asked to complete IBS Baseline Assessment Questionnaires according to Rome III.Subjects&#xD;
      that meet the criteria will receive verbal and written information about the study and&#xD;
      provide written informed consent. After meeting with the dietitian and physician who will&#xD;
      provide instructions, they will be asked to complete Combined Nutrient and Lactulose Breath&#xD;
      Test.[16] Additionally, a baseline food and symptom diary will be completed in a (minimum) 14&#xD;
      day run-in period after breath test (the first 48hr after the breath test will not be&#xD;
      included in this analysis). This diary record prior to the intervention will document&#xD;
      baseline symptom severity and capture the habitual diet of IBS patients.&#xD;
&#xD;
      Visit 2: Randomization &amp; Intervention. After the run-in period, patients will come back to&#xD;
      the clinic to receive dietary instruction ahead of starting the intervention. At the same&#xD;
      visit subjects will provide fresh stool for fermentation analysis (including short chain&#xD;
      fatty acids and pressure detection) and blood for cytokines analysis. Subjects will then be&#xD;
      randomly assigned to either low FODMAP diet (LFD) group or traditional dietary advice for IBS&#xD;
      (TDA) group by computer-generated random number table. Participants will receive food&#xD;
      instructions by a dietitian, according to their assignment. Throughout the study, only the&#xD;
      dietitian will be aware of the assignment of the intervention given. Both diet therapy will&#xD;
      last for 3 weeks, and all the subjects are instructed to complete daily food and symptom&#xD;
      diary through a provided booklet. IBS Symptoms Severity Scores (IBS-SSS) is evaluated every&#xD;
      week and the dietitian who is not aware of the allocation will make a telephone follow-up to&#xD;
      assess patient adherence.&#xD;
&#xD;
      Visit 3: End of treatment &amp; Follow-up. After 3 weeks of intervention, the participants will&#xD;
      attend a follow-up appointment and complete the IBS Post-Intervention Assessment&#xD;
      Questionnaires. Fresh stools and blood are recollected at this visit to evaluate for possible&#xD;
      change in gut microbiota and cytokines after diet intervention.&#xD;
    </textblock>
  </detailed_description>
  <overall_status>Completed</overall_status>
  <start_date type="Actual">October 10, 2017</start_date>
  <completion_date type="Actual">May 31, 2019</completion_date>
  <primary_completion_date type="Actual">May 31, 2018</primary_completion_date>
  <phase>N/A</phase>
  <study_type>Interventional</study_type>
  <has_expanded_access>No</has_expanded_access>
  <study_design_info>
    <allocation>Randomized</allocation>
    <intervention_model>Parallel Assignment</intervention_model>
    <primary_purpose>Treatment</primary_purpose>
    <masking>Triple (Participant, Investigator, Outcomes Assessor)</masking>
  </study_design_info>
  <primary_outcome>
    <measure>Compare response to diet intervention between different groups.</measure>
    <time_frame>three weeks</time_frame>
    <description>Primary endpoint will be response to 3-week of diet intervention defined by shows &gt;50 point reduction in IBS-SSS between baseline and post-intervention scores. The proportion of responders who met primary endpoint in each group will be compared.</description>
  </primary_outcome>
  <secondary_outcome>
    <measure>Improvement in abdominal pain between different groups.</measure>
    <time_frame>Three weeks</time_frame>
    <description>Compare improvement about abdominal pain during 3-week intervention period between different groups according to Food and Drug Administration (FDA) individual composite end point (≥30% reduction in mean daily abdominal pain score).</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Improvement in stool consistency between different groups.</measure>
    <time_frame>Three weeks</time_frame>
    <description>Compare improvement about stool consistency during 3-week intervention period between different groups according to Food and Drug Administration (FDA) individual composite end point (a decrease in mean daily Bristol Stool Score (BSS) value of ≥1 compared with baseline for any 2 weeks of the intervention period).</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Compare changes from baseline in abdominal pain score between different groups.</measure>
    <time_frame>Every week, last for three weeks</time_frame>
    <description>Compare group changes from baseline in abdominal pain score，averaged over each treatment week for total three weeks.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Compare changes from baseline in abdominal frequency between different groups.</measure>
    <time_frame>Every week, last for three weeks</time_frame>
    <description>Compare group changes from baseline in abdominal frequency, averaged over each treatment week for total three weeks.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Compare changes from baseline in bloating score between different groups.</measure>
    <time_frame>Every week, last for three weeks</time_frame>
    <description>Compare group changes from baseline in bloating score, averaged over each treatment week for total three weeks.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Compare changes from baseline in excessive wind score between different groups.</measure>
    <time_frame>Every week, last for three weeks</time_frame>
    <description>Compare group changes from baseline in excessive wind score, averaged over each treatment week for total three weeks.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Compare changes from baseline in stool consistency between different groups.</measure>
    <time_frame>Every week, last for three weeks</time_frame>
    <description>Compare group changes from baseline in stool consistency as measured by BSS, averaged over each treatment week for total three weeks..</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Compare changes from baseline in stool frequency between different groups.</measure>
    <time_frame>Every week, last for three weeks</time_frame>
    <description>Compare group changes from baseline in stool frequency, averaged over each treatment week for total three weeks.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Compare changes from baseline in urgency score between different groups.</measure>
    <time_frame>Every week, last for three weeks</time_frame>
    <description>Compare group changes from baseline in urgency score, averaged over each treatment week for total three weeks.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Compare changes from baseline in incomplete defecation score between different groups.</measure>
    <time_frame>Every week, last for three weeks</time_frame>
    <description>Compare group changes from baseline in incomplete defecation score, averaged over each treatment week for total three weeks.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Compare changes from baseline in quality of life between different groups.</measure>
    <time_frame>Three weeks</time_frame>
    <description>Compare group changes between baseline and post-intervention(3 weeks later) about quality of life evaluated by IBS-QOL.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Compare changes from baseline in mental health between different groups.</measure>
    <time_frame>Three weeks</time_frame>
    <description>Compare group changes between baseline and post-intervention(3 weeks later) about mental health evaluated by GAD-7 and PHQ-9.</description>
  </secondary_outcome>
  <other_outcome>
    <measure>Compare group difference about stool fermentation production before and after intervention.</measure>
    <time_frame>Three weeks</time_frame>
    <description>Compare group difference about stool fermentation production- short chain fatty acids, before and after 3-week intervention .</description>
  </other_outcome>
  <other_outcome>
    <measure>Compare group difference about fecal microbial α- diversity displayed by Shannon index before and after intervention.</measure>
    <time_frame>Three weeks</time_frame>
    <description>Fresh feces will be collected from patients at baseline and the end of the intervention (three weeks intervention), and the fecal DNA will be extracted by MOBIO PowerSoil DNA Isolation Kit according to the instructions. The 16S rRNA sequencing will be performed from the extracted DNA. Within-community diversity (α- diversity displayed by Shannon index) will be further calculated according to the sequencing results.</description>
  </other_outcome>
  <other_outcome>
    <measure>Compare group difference about fecal microbial β- diversity displayed by Principal Component Analysis (PCA) before and after intervention.</measure>
    <time_frame>Three weeks</time_frame>
    <description>Fresh feces will be collected from patients at baseline and the end of the intervention (three weeks intervention), and the fecal DNA will be extracted by MOBIO PowerSoil DNA Isolation Kit according to the instructions. The 16S rRNA sequencing will be performed from the extracted DNA. Between-community diversity (β- diversity displayed by Principal Component Analysis (PCA)) will be further calculated according to the sequencing results.</description>
  </other_outcome>
  <other_outcome>
    <measure>Compare group difference about fecal microbial communities before and after intervention.</measure>
    <time_frame>Three weeks</time_frame>
    <description>Fresh feces will be collected from patients at baseline and the end of the intervention (three weeks intervention), and the fecal DNA will be extracted by MOBIO PowerSoil DNA Isolation Kit according to the instructions. The 16S rRNA sequencing will be performed from the extracted DNA. LEfSe (linear discriminant analysis coupled with effect size measurements) will be further calculated according to the sequencing results.</description>
  </other_outcome>
  <other_outcome>
    <measure>Compare stool microbial α- diversity displayed by Shannon between responders and non-responders</measure>
    <time_frame>Baseline (0 week)</time_frame>
    <description>Fresh feces collected from responders and nonresponders to interventions at baseline will be analyzed by 16S rRNA sequencing. Within-community diversity (α- diversity displayed by Shannon index) will be further calculated according to the sequencing results.</description>
  </other_outcome>
  <other_outcome>
    <measure>Compare stool microbial β- diversity displayed by Principal Component Analysis (PCA) between responders and non-responders</measure>
    <time_frame>Baseline (0 week)</time_frame>
    <description>Fresh feces collected from responders and nonresponders to interventions at baseline will be analyzed by 16S rRNA sequencing. Between-community diversity (β- diversity displayed by Principal Component Analysis (PCA)) will be further calculated according to the sequencing results.</description>
  </other_outcome>
  <other_outcome>
    <measure>Compare stool microbial communities between responders and non-responders</measure>
    <time_frame>Baseline (0 week)</time_frame>
    <description>Fresh feces collected from responders and nonresponders to interventions at baseline will be analyzed by 16S rRNA sequencing. LEfSe (linear discriminant analysis coupled with effect size measurements) will be further calculated according to the sequencing results.</description>
  </other_outcome>
  <other_outcome>
    <measure>Compare stool fermentation production between responders and non-responders</measure>
    <time_frame>Baseline (0 week)</time_frame>
    <description>Compare stool fermentation production- short chain fatty acids, between responders and non-responders</description>
  </other_outcome>
  <other_outcome>
    <measure>Compare IBS symptom severity between responders and non-responders</measure>
    <time_frame>Baseline (0 week)</time_frame>
    <description>Compare IBS symptom severity (measured by IBS symptom severity scale(IBS-SSS)) between responders and non-responders</description>
  </other_outcome>
  <number_of_arms>2</number_of_arms>
  <enrollment type="Actual">108</enrollment>
  <condition>Irritable Bowel Syndrome</condition>
  <condition>Diet Modification</condition>
  <arm_group>
    <arm_group_label>low-FODMAPs diet</arm_group_label>
    <arm_group_type>Experimental</arm_group_type>
    <description>The low-FODMAPs diet(LFD) aims to keep oligosaccharides, fructose in excess of glucose, and polyol content at less than 0.5 g each per serving based on previously published data.&#xD;
low-FODMAPs diet therapy for 3 weeks</description>
  </arm_group>
  <arm_group>
    <arm_group_label>Traditional dietary advice</arm_group_label>
    <arm_group_type>Placebo Comparator</arm_group_type>
    <description>Traditional dietary advice (TDA) will focus more on how and when to eat rather than on what foods to ingest . Patients will be instructed to regularly eat, never too much or too little, never to be hungry or too full; to eat in peace and to chew thoroughly; reduce intake of fatty, spicy food, fiber, coffee and alcohol during the intervention period&#xD;
Traditional dietary advice for 3 weeks</description>
  </arm_group>
  <intervention>
    <intervention_type>Dietary Supplement</intervention_type>
    <intervention_name>low-FODMAPs diet</intervention_name>
    <description>The low-FODMAPs diet(LFD) aims to keep oligosaccharides, fructose in excess of glucose, and polyol content at less than 0.5 g each per serving based on previously published data.&#xD;
low-FODMAPs diet therapy for 3 weeks</description>
    <arm_group_label>low-FODMAPs diet</arm_group_label>
  </intervention>
  <intervention>
    <intervention_type>Dietary Supplement</intervention_type>
    <intervention_name>Traditional dietary advice</intervention_name>
    <description>Traditional dietary advice(TDA) will focus more on how and when to eat rather than on what foods to ingest . Patients will be instructed to regularly eat, never too much or too little, never to be hungry or too full; to eat in peace and to chew thoroughly; reduce intake of fatty, spicy food, fiber, coffee and alcohol during the intervention period&#xD;
traditional dietary advice for 3 weeks</description>
    <arm_group_label>Traditional dietary advice</arm_group_label>
  </intervention>
  <eligibility>
    <criteria>
      <textblock>
        Inclusion Criteria:&#xD;
&#xD;
          -  18-65 years old.&#xD;
&#xD;
          -  Meet Rome Rome III criteria for IBS-D.&#xD;
&#xD;
          -  All these patients should have no abnormality in blood, stool analysis or colonoscopy&#xD;
             within the previous 2 years.&#xD;
&#xD;
          -  No GI alarm symptoms.&#xD;
&#xD;
        Exclusion Criteria:&#xD;
&#xD;
          -  Presence of a severe cardiac, hepatic, nephritic, neurologic disease.&#xD;
&#xD;
          -  Presence of mental disorders caused by schizophrenia, organic brain disorder or&#xD;
             physical disease.&#xD;
&#xD;
          -  Other comorbid medical conditions (eg.unstable diabetes, unstable thyroid disease).&#xD;
&#xD;
          -  Previous abdominal surgery except appendectomy or hysterectomy.&#xD;
&#xD;
          -  Pregnant or lactating women.&#xD;
&#xD;
          -  Use of probiotics, prebiotics, lactulose, antidiarrheal agents or bowel preparation&#xD;
             within the 4 weeks prior to the study.&#xD;
&#xD;
          -  Participation in any other form of dietary therapy within the 4 weeks prior to the&#xD;
             study.&#xD;
&#xD;
          -  Difficulties in communication.&#xD;
      </textblock>
    </criteria>
    <gender>All</gender>
    <minimum_age>18 Years</minimum_age>
    <maximum_age>65 Years</maximum_age>
    <healthy_volunteers>No</healthy_volunteers>
  </eligibility>
  <overall_official>
    <last_name>Yawen Zhang, MM</last_name>
    <role>Principal Investigator</role>
    <affiliation>Sir Run Run Shaw Hospital</affiliation>
  </overall_official>
  <overall_official>
    <last_name>Lijun Feng</last_name>
    <role>Principal Investigator</role>
    <affiliation>Sir Run Run Shaw Hospital</affiliation>
  </overall_official>
  <location>
    <facility>
      <name>Sir Run Run Shaw Hospital , College of Medicine, Zhejiang University</name>
      <address>
        <city>Hangzhou</city>
        <state>Zhe Jiang</state>
        <zip>310016</zip>
        <country>China</country>
      </address>
    </facility>
  </location>
  <location_countries>
    <country>China</country>
  </location_countries>
  <verification_date>September 2019</verification_date>
  <study_first_submitted>July 20, 2017</study_first_submitted>
  <study_first_submitted_qc>October 1, 2017</study_first_submitted_qc>
  <study_first_posted type="Actual">October 6, 2017</study_first_posted>
  <last_update_submitted>September 11, 2019</last_update_submitted>
  <last_update_submitted_qc>September 11, 2019</last_update_submitted_qc>
  <last_update_posted type="Actual">September 12, 2019</last_update_posted>
  <responsible_party>
    <responsible_party_type>Principal Investigator</responsible_party_type>
    <investigator_affiliation>Sir Run Run Shaw Hospital</investigator_affiliation>
    <investigator_full_name>DAI Ning</investigator_full_name>
    <investigator_title>Director of Gastroenterology department</investigator_title>
  </responsible_party>
  <keyword>low-FODMAP</keyword>
  <keyword>Irritable Bowel Syndrome</keyword>
  <keyword>stool fermentation</keyword>
  <keyword>Breath test</keyword>
  <condition_browse>
    <!-- CAUTION:  The following MeSH terms are assigned with an imperfect algorithm            -->
    <mesh_term>Irritable Bowel Syndrome</mesh_term>
    <mesh_term>Syndrome</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/NCT03304041
org study id: 20170116-2
nct id: NCT03304041
lead sponsor: 
collaborator: 
collaborator: 
collaborator: 
has dmc: Yes
is fda regulated drug: No
is fda regulated device: No
The primary aim of our study is to carry out a randomized trial to evaluate the efficacy of
      low-FODMAPs dietary therapy compared to conventional therapy for IBS patients recruited from
      tertiary hospitals in China. Secondary aims of this research include an analysis of clinical,
      physiological and microbiological factors that may predict IBS patient response to this
      dietary intervention.
Visit 1：Enrollment & Screening & Run-in period Patients who meet the inclusion criteria will
      be asked to complete IBS Baseline Assessment Questionnaires according to Rome III.Subjects
      that meet the criteria will receive verbal and written information about the study and
      provide written informed consent. After meeting with the dietitian and physician who will
      provide instructions, they will be asked to complete Combined Nutrient and Lactulose Breath
      Test.[16] Additionally, a baseline food and symptom diary will be completed in a (minimum) 14
      day run-in period after breath test (the first 48hr after the breath test will not be
      included in this analysis). This diary record prior to the intervention will document
      baseline symptom severity and capture the habitual diet of IBS patients.

      Visit 2: Randomization & Intervention. After the run-in period, patients will come back to
      the clinic to receive dietary instruction ahead of starting the intervention. At the same
      visit subjects will provide fresh stool for fermentation analysis (including short chain
      fatty acids and pressure detection) and blood for cytokines analysis. Subjects will then be
      randomly assigned to either low FODMAP diet (LFD) group or traditional dietary advice for IBS
      (TDA) group by computer-generated random number table. Participants will receive food
      instructions by a dietitian, according to their assignment. Throughout the study, only the
      dietitian will be aware of the assignment of the intervention given. Both diet therapy will
      last for 3 weeks, and all the subjects are instructed to complete daily food and symptom
      diary through a provided booklet. IBS Symptoms Severity Scores (IBS-SSS) is evaluated every
      week and the dietitian who is not aware of the allocation will make a telephone follow-up to
      assess patient adherence.

      Visit 3: End of treatment & Follow-up. After 3 weeks of intervention, the participants will
      attend a follow-up appointment and complete the IBS Post-Intervention Assessment
      Questionnaires. Fresh stools and blood are recollected at this visit to evaluate for possible
      change in gut microbiota and cytokines after diet intervention.
allocation: Randomized
intervention model: Parallel Assignment
primary purpose: Treatment
masking: Triple (Participant, Investigator, Outcomes Assessor)
measure: Compare response to diet intervention between different groups.
time frame: three weeks
description: Primary endpoint will be response to 3-week of diet intervention defined by shows >50 point reduction in IBS-SSS between baseline and post-intervention scores. The proportion of responders who met primary endpoint in each group will be compared.
measure: Improvement in abdominal pain between different groups.
time frame: Three weeks
description: Compare improvement about abdominal pain during 3-week intervention period between different groups according to Food and Drug Administration (FDA) individual composite end point (≥30% reduction in mean daily abdominal pain score).
measure: Improvement in stool consistency between different groups.
time frame: Three weeks
description: Compare improvement about stool consistency during 3-week intervention period between different groups according to Food and Drug Administration (FDA) individual composite end point (a decrease in mean daily Bristol Stool Score (BSS) value of ≥1 compared with baseline for any 2 weeks of the intervention period).
measure: Compare changes from baseline in abdominal pain score between different groups.
time frame: Every week, last for three weeks
description: Compare group changes from baseline in abdominal pain score，averaged over each treatment week for total three weeks.
measure: Compare changes from baseline in abdominal frequency between different groups.
time frame: Every week, last for three weeks
description: Compare group changes from baseline in abdominal frequency, averaged over each treatment week for total three weeks.
measure: Compare changes from baseline in bloating score between different groups.
time frame: Every week, last for three weeks
description: Compare group changes from baseline in bloating score, averaged over each treatment week for total three weeks.
measure: Compare changes from baseline in excessive wind score between different groups.
time frame: Every week, last for three weeks
description: Compare group changes from baseline in excessive wind score, averaged over each treatment week for total three weeks.
measure: Compare changes from baseline in stool consistency between different groups.
time frame: Every week, last for three weeks
description: Compare group changes from baseline in stool consistency as measured by BSS, averaged over each treatment week for total three weeks..
measure: Compare changes from baseline in stool frequency between different groups.
time frame: Every week, last for three weeks
description: Compare group changes from baseline in stool frequency, averaged over each treatment week for total three weeks.
measure: Compare changes from baseline in urgency score between different groups.
time frame: Every week, last for three weeks
description: Compare group changes from baseline in urgency score, averaged over each treatment week for total three weeks.
measure: Compare changes from baseline in incomplete defecation score between different groups.
time frame: Every week, last for three weeks
description: Compare group changes from baseline in incomplete defecation score, averaged over each treatment week for total three weeks.
measure: Compare changes from baseline in quality of life between different groups.
time frame: Three weeks
description: Compare group changes between baseline and post-intervention(3 weeks later) about quality of life evaluated by IBS-QOL.
measure: Compare changes from baseline in mental health between different groups.
time frame: Three weeks
description: Compare group changes between baseline and post-intervention(3 weeks later) about mental health evaluated by GAD-7 and PHQ-9.
measure: Compare group difference about stool fermentation production before and after intervention.
time frame: Three weeks
description: Compare group difference about stool fermentation production- short chain fatty acids, before and after 3-week intervention .
measure: Compare group difference about fecal microbial α- diversity displayed by Shannon index before and after intervention.
time frame: Three weeks
description: Fresh feces will be collected from patients at baseline and the end of the intervention (three weeks intervention), and the fecal DNA will be extracted by MOBIO PowerSoil DNA Isolation Kit according to the instructions. The 16S rRNA sequencing will be performed from the extracted DNA. Within-community diversity (α- diversity displayed by Shannon index) will be further calculated according to the sequencing results.
measure: Compare group difference about fecal microbial β- diversity displayed by Principal Component Analysis (PCA) before and after intervention.
time frame: Three weeks
description: Fresh feces will be collected from patients at baseline and the end of the intervention (three weeks intervention), and the fecal DNA will be extracted by MOBIO PowerSoil DNA Isolation Kit according to the instructions. The 16S rRNA sequencing will be performed from the extracted DNA. Between-community diversity (β- diversity displayed by Principal Component Analysis (PCA)) will be further calculated according to the sequencing results.
measure: Compare group difference about fecal microbial communities before and after intervention.
time frame: Three weeks
description: Fresh feces will be collected from patients at baseline and the end of the intervention (three weeks intervention), and the fecal DNA will be extracted by MOBIO PowerSoil DNA Isolation Kit according to the instructions. The 16S rRNA sequencing will be performed from the extracted DNA. LEfSe (linear discriminant analysis coupled with effect size measurements) will be further calculated according to the sequencing results.
measure: Compare stool microbial α- diversity displayed by Shannon between responders and non-responders
time frame: Baseline (0 week)
description: Fresh feces collected from responders and nonresponders to interventions at baseline will be analyzed by 16S rRNA sequencing. Within-community diversity (α- diversity displayed by Shannon index) will be further calculated according to the sequencing results.
measure: Compare stool microbial β- diversity displayed by Principal Component Analysis (PCA) between responders and non-responders
time frame: Baseline (0 week)
description: Fresh feces collected from responders and nonresponders to interventions at baseline will be analyzed by 16S rRNA sequencing. Between-community diversity (β- diversity displayed by Principal Component Analysis (PCA)) will be further calculated according to the sequencing results.
measure: Compare stool microbial communities between responders and non-responders
time frame: Baseline (0 week)
description: Fresh feces collected from responders and nonresponders to interventions at baseline will be analyzed by 16S rRNA sequencing. LEfSe (linear discriminant analysis coupled with effect size measurements) will be further calculated according to the sequencing results.
measure: Compare stool fermentation production between responders and non-responders
time frame: Baseline (0 week)
description: Compare stool fermentation production- short chain fatty acids, between responders and non-responders
measure: Compare IBS symptom severity between responders and non-responders
time frame: Baseline (0 week)
description: Compare IBS symptom severity (measured by IBS symptom severity scale(IBS-SSS)) between responders and non-responders
arm group label: low-FODMAPs diet
arm group type: Experimental
description: The low-FODMAPs diet(LFD) aims to keep oligosaccharides, fructose in excess of glucose, and polyol content at less than 0.5 g each per serving based on previously published data.
low-FODMAPs diet therapy for 3 weeks
arm group label: Traditional dietary advice
arm group type: Placebo Comparator
description: Traditional dietary advice (TDA) will focus more on how and when to eat rather than on what foods to ingest . Patients will be instructed to regularly eat, never too much or too little, never to be hungry or too full; to eat in peace and to chew thoroughly; reduce intake of fatty, spicy food, fiber, coffee and alcohol during the intervention period
Traditional dietary advice for 3 weeks
intervention type: Dietary Supplement
intervention name: low-FODMAPs diet
description: The low-FODMAPs diet(LFD) aims to keep oligosaccharides, fructose in excess of glucose, and polyol content at less than 0.5 g each per serving based on previously published data.
low-FODMAPs diet therapy for 3 weeks
arm group label: low-FODMAPs diet
intervention type: Dietary Supplement
intervention name: Traditional dietary advice
description: Traditional dietary advice(TDA) will focus more on how and when to eat rather than on what foods to ingest . Patients will be instructed to regularly eat, never too much or too little, never to be hungry or too full; to eat in peace and to chew thoroughly; reduce intake of fatty, spicy food, fiber, coffee and alcohol during the intervention period
traditional dietary advice for 3 weeks
arm group label: Traditional dietary advice
criteria: 
gender: All
minimum age: 18 Years
maximum age: 65 Years
healthy volunteers: No
last name: Yawen Zhang, MM
role: Principal Investigator
affiliation: Sir Run Run Shaw Hospital
last name: Lijun Feng
role: Principal Investigator
affiliation: Sir Run Run Shaw Hospital
facility: 
country: China
responsible party type: Principal Investigator
investigator affiliation: Sir Run Run Shaw Hospital
investigator full name: DAI Ning
investigator title: Director of Gastroenterology department
mesh term: Irritable Bowel Syndrome
mesh term: Syndrome