Irritable Bowel Syndrome
Conditions
Keywords
Low FODMAP Diet, Mediterranean Diet
Brief summary
This study is being completed to determine if the Mediterranean (MD) and low FODMAP (fermentable, oligosaccharides, disaccharides, monosaccharides, and polyols) diets are comparable in the effectiveness to treat Irritable Bowel Syndrome (IBS). The study team hypothesizes that: * The low FODMAP and Mediterranean groups will achieve a similar improvement in abdominal pain * Both groups will achieve similar improvements in bloating, overall IBS symptom severity, and adequate relief
Interventions
OTHERDiet low in all FODMAP groups
Randomized participants will eat this diet for 4 weeks (all meals and snacks will be provided). Participants will only eat the study food for this intervention. Participants will be asked to complete surveys, food diaries, and have blood and stools samples pre and post treatment.
OTHERDiet - Mediterranean
Randomized participants will eat this diet for 4 weeks (all meals and snacks will be provided). Participants will only eat the study food for this intervention. Participants will be asked to complete surveys, food diaries, and have blood and stools samples pre and post treatment.
Sponsors
ModifyHealth
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
University of Michigan
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Investigator)
Masking description
Participant and investigators will not know what study cohort participants have been randomized into.
Intervention model description
Subjects meeting all eligibility criteria will be randomized in a 1:1 ratio to receive either the MD or the LFD for a four-week period.
Eligibility
Sex/Gender
ALL
Age
18 Years to 70 Years
Healthy volunteers
No
Inclusion criteria
* Patients with IBS-D (diarrhea-predominant IBS) or IBS-M (IBS with mixed subtype) diagnosed per Rome IV questionnaire and without any unexplained alarm features (rectal bleeding, weight loss, nocturnal symptoms, personal history of celiac disease, microscopic colitis, inflammatory bowel disease) * Aged 18-70 years at the time of screening * Weekly average of worst daily (in the past 24 hours) abdominal pain score of ≥3.0 on a 0-to-10-point scale * At least 80 percent compliance in daily questionnaire entries during the 7-day screening period
Exclusion criteria
* Subjects adhering to any dietary IBS treatment such as the low-fodmap diet, or gluten-free diet, Mediterranean currently or within the past 6 months * Subjects with a known food allergy to eggs, seafood, peanuts, tree nuts or milk (subjects with lactose intolerance that are experiencing IBS symptoms while on a lactose-free diet will not be excluded from the study). * Subjects with a history of poorly controlled insulin-dependent or non-insulin-dependent diabetes * Subjects with a known history of organic Gastrointestinal (GI) disease (i.e., celiac disease, inflammatory bowel disease or microscopic colitis) * Subjects with a history of an eating disorder requiring medical or behavioral treatment within the past 10 years. * Subjects with prior small bowel or colonic surgery (excluding appendectomy or cholecystectomy if over 6 months since these 2 procedures) * Oral antibiotic use in the past 3 months * Any planned significant changes in dietary or exercise regimen within 30 days prior to Screening or during the study. * Currently pregnant or breastfeeding.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Proportion of Participants Who Are Responders Based on the Abdominal Pain Intensity Score for at Least 2 of 4 Weeks | 4 weeks | Results reflect the participants who were weekly responders for at least 2 of the 4 weeks based on their abdominal pain intensity score. The abdominal pain score was a single-question, 11-point numeric rating scale in which 0 represented no abdominal pain and 11 represented the worst possible abdominal pain. Once per day, subjects reported their worst daily (in the past 24 hours) abdominal pain. A weekly responder was defined as a participant whose score decreased in the weekly average of worst abdominal pain in the past 24 hours by at least 30% compared with baseline. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Proportion of Participants Who Are Weekly Responders to Adequate Relief Symptom Assessment for at Least 2 of 4 Weeks | 4 weeks | Results reflect the participants who were weekly responders based on the adequate relief symptom assessment for at least 2 of the 4 weeks. Participants provided a binary (yes or no) response to rate the adequacy of relief of global irritable bowel syndrome (IBS) symptoms at the start of the study and weekly thereafter. A weekly responder was defined as a participant who achieved adequate relief in symptoms in at least 2 out of 4 weeks of the treatment period. |
| Proportion of Participants Who Are Weekly Responders Based on the Irritable Bowel Severity Scoring System (IBS-SSS) Modified Version for at Least 2 of the 4 Weeks | 4 weeks | Results reflect participants who were weekly responders for at least 2 of the 4 weeks based on their scores on a modified version of the IBS-SSS. This version of the IBS-SSS was comprised of 5 questions participants answered based on their stomach and bowels. The total score for this modified version of the IBS-SSS was 0-500, with 0 indicating no IBS symptoms and 500 indicating the highest amount of IBS symptoms. A weekly responder was defined as a participant whose score decreased in the weekly IBS-SSS by at least 50 points compared with baseline. |
| Change in Mean Score of the Irritable Bowel Severity Scoring System (IBS-SSS) Modified Version | Baseline, 4 weeks | The modified version of the IBS-SSS was comprised of 5 questions participants answered based on their stomach and bowels. The total score for this modified version of the IBS-SSS was 0-500, with 0 indicating no IBS symptoms and 500 indicating the highest amount of IBS symptoms. The results represent the mean change from baseline minus 4 weeks. |
| Proportion of Participants Who Are Weekly Responders to Bloating for at Least 2 of the 4 Weeks | 4 weeks | Results reflect the number of participants who were weekly responders based on their abdominal bloating score for at least 2 of 4 weeks. The abdominal bloating score was a single-question, 11-point numeric rating scale in which 0 represented no abdominal bloating and 11 represented the worst possible abdominal bloating. Once per day, participants reported their worst daily (in the past 24 hours) abdominal bloating. A weekly responder was defined as a participant whose score decreased in the weekly average of worst bloating in the past 24 hours by at least 30% compared with baseline. |
| Participants Who Are Weekly Responders to Stool Consistency Based on the Bristol Stool Scale (BSS) for at Least 2 of the 4 Weeks | 4 weeks | Results reflect the participants who were weekly responders based on their stool consistency assessment for at least 2 of 4 weeks. A stool consistency weekly responder was defined as a participant with a 50% or greater reduction in the number of days per week with at least one abnormal stool. Stools that scored as 1 or 2 (hard stool) or 6 or 7 (liquid stool) on the BSS were defined as abnormal. |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Diet Low in All FODMAP Groups Diet low in all FODMAP groups: Randomized participants will eat this diet for 4 weeks (all meals and snacks will be provided). Participants will only eat the study food for this intervention. Participants will be asked to complete surveys, food diaries, and have blood and stools samples pre and post treatment. | 11 |
| Diet - Mediterranean Diet - Mediterranean: Randomized participants will eat this diet for 4 weeks (all meals and snacks will be provided). Participants will only eat the study food for this intervention. Participants will be asked to complete surveys, food diaries, and have blood and stools samples pre and post treatment. | 15 |
| Total | 26 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Overall Study | Adverse Event | 1 | 1 |
| Overall Study | Received antibiotics - excluded | 0 | 1 |
| Overall Study | Withdrawal by Subject | 0 | 3 |
Baseline characteristics
| Characteristic | Diet Low in All FODMAP Groups | Total | Diet - Mediterranean |
|---|---|---|---|
| Age, Continuous | 45.09 years STANDARD_DEVIATION 19.5 | 41.1 years STANDARD_DEVIATION 15.3 | 38.13 years STANDARD_DEVIATION 11.3 |
| Ethnicity (NIH/OMB) Hispanic or Latino | 0 Participants | 0 Participants | 0 Participants |
| Ethnicity (NIH/OMB) Not Hispanic or Latino | 0 Participants | 0 Participants | 0 Participants |
| Ethnicity (NIH/OMB) Unknown or Not Reported | 11 Participants | 26 Participants | 15 Participants |
| Race (NIH/OMB) American Indian or Alaska Native | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Asian | 0 Participants | 1 Participants | 1 Participants |
| Race (NIH/OMB) Black or African American | 1 Participants | 3 Participants | 2 Participants |
| Race (NIH/OMB) More than one race | 0 Participants | 1 Participants | 1 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) White | 10 Participants | 21 Participants | 11 Participants |
| Region of Enrollment United States | 11 Participants | 26 Participants | 15 Participants |
| Sex/Gender, Customized Female | 9 Participants | 23 Participants | 14 Participants |
| Sex/Gender, Customized Male | 1 Participants | 2 Participants | 1 Participants |
| Sex/Gender, Customized Non-Binary | 1 Participants | 1 Participants | 0 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 11 | 0 / 15 |
| other Total, other adverse events | 1 / 11 | 1 / 15 |
| serious Total, serious adverse events | 0 / 11 | 0 / 15 |
Outcome results
Primary
Proportion of Participants Who Are Responders Based on the Abdominal Pain Intensity Score for at Least 2 of 4 Weeks
Results reflect the participants who were weekly responders for at least 2 of the 4 weeks based on their abdominal pain intensity score. The abdominal pain score was a single-question, 11-point numeric rating scale in which 0 represented no abdominal pain and 11 represented the worst possible abdominal pain. Once per day, subjects reported their worst daily (in the past 24 hours) abdominal pain. A weekly responder was defined as a participant whose score decreased in the weekly average of worst abdominal pain in the past 24 hours by at least 30% compared with baseline.
Time frame: 4 weeks
Population: Results are based on a modified intent to treat (mITT) analysis. Participants categorized in the Participant Flow as Withdrawal by Subject were not included in the mITT analysis.
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Diet Low in All FODMAP Groups | Proportion of Participants Who Are Responders Based on the Abdominal Pain Intensity Score for at Least 2 of 4 Weeks | 9 Participants |
| Diet - Mediterranean | Proportion of Participants Who Are Responders Based on the Abdominal Pain Intensity Score for at Least 2 of 4 Weeks | 8 Participants |
p-value: 1Fisher Exact
Secondary
Change in Mean Score of the Irritable Bowel Severity Scoring System (IBS-SSS) Modified Version
The modified version of the IBS-SSS was comprised of 5 questions participants answered based on their stomach and bowels. The total score for this modified version of the IBS-SSS was 0-500, with 0 indicating no IBS symptoms and 500 indicating the highest amount of IBS symptoms. The results represent the mean change from baseline minus 4 weeks.
Time frame: Baseline, 4 weeks
Population: Results are based on a per-protocol analysis.
| Arm | Measure | Value (MEAN) |
|---|---|---|
| Diet Low in All FODMAP Groups | Change in Mean Score of the Irritable Bowel Severity Scoring System (IBS-SSS) Modified Version | -105.5 score on a scale |
| Diet - Mediterranean | Change in Mean Score of the Irritable Bowel Severity Scoring System (IBS-SSS) Modified Version | -60 score on a scale |
p-value: 0.02Wilcoxon (Mann-Whitney)
Secondary
Participants Who Are Weekly Responders to Stool Consistency Based on the Bristol Stool Scale (BSS) for at Least 2 of the 4 Weeks
Results reflect the participants who were weekly responders based on their stool consistency assessment for at least 2 of 4 weeks. A stool consistency weekly responder was defined as a participant with a 50% or greater reduction in the number of days per week with at least one abnormal stool. Stools that scored as 1 or 2 (hard stool) or 6 or 7 (liquid stool) on the BSS were defined as abnormal.
Time frame: 4 weeks
Population: Results are based on a mITT analysis. Participants categorized in the Participant Flow as Withdrawal by Subject were not included in the mITT analysis.
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Diet Low in All FODMAP Groups | Participants Who Are Weekly Responders to Stool Consistency Based on the Bristol Stool Scale (BSS) for at Least 2 of the 4 Weeks | 2 Participants |
| Diet - Mediterranean | Participants Who Are Weekly Responders to Stool Consistency Based on the Bristol Stool Scale (BSS) for at Least 2 of the 4 Weeks | 0 Participants |
p-value: 0.48Fisher Exact
Secondary
Proportion of Participants Who Are Weekly Responders Based on the Irritable Bowel Severity Scoring System (IBS-SSS) Modified Version for at Least 2 of the 4 Weeks
Results reflect participants who were weekly responders for at least 2 of the 4 weeks based on their scores on a modified version of the IBS-SSS. This version of the IBS-SSS was comprised of 5 questions participants answered based on their stomach and bowels. The total score for this modified version of the IBS-SSS was 0-500, with 0 indicating no IBS symptoms and 500 indicating the highest amount of IBS symptoms. A weekly responder was defined as a participant whose score decreased in the weekly IBS-SSS by at least 50 points compared with baseline.
Time frame: 4 weeks
Population: Results are based on a mITT analysis. Participants categorized in the Participant Flow as Withdrawal by Subject were not included in the mITT analysis.
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Diet Low in All FODMAP Groups | Proportion of Participants Who Are Weekly Responders Based on the Irritable Bowel Severity Scoring System (IBS-SSS) Modified Version for at Least 2 of the 4 Weeks | 9 Participants |
| Diet - Mediterranean | Proportion of Participants Who Are Weekly Responders Based on the Irritable Bowel Severity Scoring System (IBS-SSS) Modified Version for at Least 2 of the 4 Weeks | 5 Participants |
p-value: 0.18Fisher Exact
Secondary
Proportion of Participants Who Are Weekly Responders to Adequate Relief Symptom Assessment for at Least 2 of 4 Weeks
Results reflect the participants who were weekly responders based on the adequate relief symptom assessment for at least 2 of the 4 weeks. Participants provided a binary (yes or no) response to rate the adequacy of relief of global irritable bowel syndrome (IBS) symptoms at the start of the study and weekly thereafter. A weekly responder was defined as a participant who achieved adequate relief in symptoms in at least 2 out of 4 weeks of the treatment period.
Time frame: 4 weeks
Population: Results are based on a mITT analysis. Participants categorized in the Participant Flow as Withdrawal by Subject were not included in the mITT analysis.
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Diet Low in All FODMAP Groups | Proportion of Participants Who Are Weekly Responders to Adequate Relief Symptom Assessment for at Least 2 of 4 Weeks | 6 Participants |
| Diet - Mediterranean | Proportion of Participants Who Are Weekly Responders to Adequate Relief Symptom Assessment for at Least 2 of 4 Weeks | 3 Participants |
p-value: 0.39Fisher Exact
Secondary
Proportion of Participants Who Are Weekly Responders to Bloating for at Least 2 of the 4 Weeks
Results reflect the number of participants who were weekly responders based on their abdominal bloating score for at least 2 of 4 weeks. The abdominal bloating score was a single-question, 11-point numeric rating scale in which 0 represented no abdominal bloating and 11 represented the worst possible abdominal bloating. Once per day, participants reported their worst daily (in the past 24 hours) abdominal bloating. A weekly responder was defined as a participant whose score decreased in the weekly average of worst bloating in the past 24 hours by at least 30% compared with baseline.
Time frame: 4 weeks
Population: Results are based on a mITT analysis. Participants categorized in the Participant Flow as Withdrawal by Subject were not included in the mITT analysis.
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Diet Low in All FODMAP Groups | Proportion of Participants Who Are Weekly Responders to Bloating for at Least 2 of the 4 Weeks | 8 Participants |
| Diet - Mediterranean | Proportion of Participants Who Are Weekly Responders to Bloating for at Least 2 of the 4 Weeks | 5 Participants |
p-value: 0.39Fisher Exact