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A Mediterranean Approach to Low FODMAP Diet (MED-LFD) for Managing IBS Symptoms

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Know the risks and potential benefits of clinical studies and talk to your health care provider before participating. Read our disclaimer for details. Identifier: NCT03997708
Recruitment Status : Recruiting
First Posted : June 25, 2019
Last Update Posted : December 18, 2019
Department of Gastroenterology, Central Clinical School, Monash University
Information provided by (Responsible Party):
Arezina Kasti, Attikon Hospital

Brief Summary:
Irritable Bowel Syndrome (IBS) is a common functional gastrointestinal disorder characterized by absence of any organic cause. The vast majority of patients associate their symptoms with specific food consumption, creating the need for developing a new therapeutic approach based on altering the dietary habits. The aim of the study focuses in the comparison of the efficacy of two dietary patterns, the adjusted to the Mediterranean Diet Low FODMAP Diet (MED-LFD) and the nutritional guidelines of the British National Institute for Health and Care Excellence (mNICE) Managing IBS.

Condition or disease Intervention/treatment Phase
Irritable Bowel Syndrome With Diarrhea Other: Med-LFD Other: Nutritional Guidelines of the British National Institute for Health and Care Excellence (NICE) Managing IBS Not Applicable

Detailed Description:

Irritable Bowel Syndrome (IBS) is a functional gastrointestinal disorder. Patients associate their symptoms with specific foods consumption, creating the need for developing a new therapeutic approach based on altering the dietary intake of these patients. Low FODMAP Diet is often used as a first-line treatment based on observations showing that short-chain carbohydrates are not adequatetly absorbed in the small intestine and exacerbate the symptoms of IBS. Additionally, the Mediterranean diet is a cultural heritage representative of all the countries surrounded by the Mediterranean Sea, described as a diet rich in herbal foods (cereals, fruits, vegetables, legumes, nuts, olives), with olive oil as the main consumption of fats, high to moderate consumption of fish and seafood, moderate consumption of eggs, poultry, dairy products and alcohol and low consumption of red meat. On the other hand, the nutritional recommendations of British National Institute for Health and Care Excellence (mNICE) managing IBS were created on the grounds of systematic reviews and are based on dietary and lifestyle modifications about caffeine, alcohol, fizzy drinks, fibre, resistant starch, fruits, sorbitol, oat and linseed consumption, meal patterns, probiotics and physical activity.

The direct aim of the study is to compare the efficacy of two dietary patterns, the MED-LFD and the nutritional recommendations of mNICE managing IBS. Efficacy will be assessed based on the severity of symptoms. Additionally, possible improvements in quality of life and relief of symptoms post intervention between the two groups will be evaluated.

The sample was calculated to 108 participants with prespecified statistical power 80%, level of significance α=0.05 and 10% adjustment for non-compliance in each group to detect an increase in the primary outcome measure from 59 in the mNICE group to 100 in the MED-LFD group (standard deviation of outcome=60). The above hypothesis of the means was based in the meta-analysis of Peter Varju, et al. 2017. Patients will be recruited by the Department of Clinical Nutrition, Attikon University General Hospital, where the nutritional intervention will be carried out.

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Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 108 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single (Outcomes Assessor)
Primary Purpose: Supportive Care
Official Title: Mediterranean Diet Adjusted to Low FODMAP Diet (MED-LFD) vs mNICE Guidelines for Improving IBS Symptoms: a New Approach for Managing IBS
Actual Study Start Date : September 1, 2019
Estimated Primary Completion Date : June 3, 2021
Estimated Study Completion Date : June 3, 2022

Arm Intervention/treatment
Active Comparator: Group A
MED-LFD Diet (diet A) for 2 - 6 weeks. After this period there will be a reintroduction phase protocol that will last 4-6 weeks.
Other: Med-LFD
All participants of this group at phase 1 (elimination phase), will initially follow the Med- LFD (2-6 weeks). At phase 2 (reintroduction phase), patients will gradually reintroduce foods rich in FODMAPs (6-8 weeks) and test their tolerance. At phase 3 (maintenance phase), following the reintroduction of foods rich in FODMAPs, patients will follow an individualized diet based on their personal tolerance (a combination of high and low FODMAPs).

Active Comparator: Group B
Diet according to guidelines from the National Institute for Health and Care Excellent (mNICE) Managing IBS (diet B) for 14 weeks.
Other: Nutritional Guidelines of the British National Institute for Health and Care Excellence (NICE) Managing IBS
All participants of this group will be informed to follow a diet based on the nutritional guidelines of the British National Institute for Health and Care Excellence (NICE) for Managing IBS for 8 weeks.

Primary Outcome Measures :
  1. Change of symptoms severity pre and post intervention using a specialized questionnaire. [ Time Frame: 6 - 8 weeks ]
    IBS- SSS contains 5 specific questions with instructions on how to score them. Each of the five questions (pain severity, pain frequency, abdominal distension severity, bowel movement satisfaction, quality of life) ranges from 0 to a maximum score of 100 using a visual analog scale (VAS) with total scores ranging from 0 to 500, with higher scores indicating more severe symptoms. Subjects can be categorized as having mild (75-175), moderate (175-300), or severe (>300) IBS. A decrease of 50 points is associated with a clinically meaningful improvement.

Secondary Outcome Measures :
  1. Assessment of IBS related quality of life with a specialized questionnaire pre and post intervention between groups. [ Time Frame: 6 - 8 weeks ]
    IBS-QOL - a measure that assesses the degree to which IBS interfered with quality of life over the past 30 days. It is a self-report quality of life measure, which includes domains such as dysphoria, interference with activity, body image, health worry, food avoidance, social relation, sexual and relationship issues. Each of them is rated based on the Likert scale from 1 to 5, the higher the score the lower the quality of life is. The overall score ranges between 34 - 170. A decrease of 10 points or more is a significant improvement.

  2. Assessment of general quality of life pre and post intervention between groups [ Time Frame: 6 - 8 weeks ]
    12-Item Short Form Survey (SF-12) is a 12-item questionnaire used to assess generic health outcomes from the patient's perspective, covering the eight domains of health outcomes: physical functioning, role-physical, bodily pain, general health, vitality, social functioning, role-emotional & mental health. The items are weighted and summed to provide physical and mental health scores (PCS and MCS). The two composite scores are computed using the scores on the questions that range from 0 to 100, with higher score indicating better health.

  3. Adequate relief of symptoms after the intervention. [ Time Frame: Once per week ]
    Adequate relief (IBS-AR) is a single item questionnaire of pain and discomfort. It poses the question "Over the past week have you had adequate relief of your IBS symptoms?", with a positive or negative answer. Adequate relief is defined as 50% positive answers within the study period, for the purposes of the trial.

  4. Assessment of symptoms burden any in general pre and post intervention. [ Time Frame: 6 - 8 weeks ]
    The GSRS questionnaire was originally developed for dyspeptic patients but was later validated in patients with IBS. The GSRS is a 15-item questionnaire designed to assess common gastrointestinal symptoms. The questionnaire has five subscales, reflux, diarrhea, constipation, indigestion, and abdominal pain, with subscale scores ranging from 1 (no discomfort) to 7 (severe discomfort). Higher scores represent higher symptom burden.

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

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Ages Eligible for Study:   18 Years to 65 Years   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Fulfillment of the Rome IV criteria for IBS (IBS-D, IBS-M, IBS-U)
  • Provision of written informed consent.
  • Commitment of availability throughout the study period.
  • IBS-SSS > 175

Exclusion Criteria:

  • Any concomitant disease requiring specialized nutrition (e.g. renal failure, diabetes, celiac disease, cerebrovascular disease of the central nervous system, major surgical cavity).
  • Pregnancy.
  • Breastfeeding.
  • IBS-C (Bristol Scale type 1 - 2)

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT03997708

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Contact: Arezina N. Kasti 6942917860 ext 6942917860

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Attikon University General Hospital Recruiting
Athens, Greece, 12462
Contact: Arezina Kasti    2105832565 ext +30   
Sponsors and Collaborators
Attikon Hospital
Department of Gastroenterology, Central Clinical School, Monash University
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Study Director: Konstantinos Triantafyllou Attikon Hospital
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Responsible Party: Arezina Kasti, Head of Dpt of Clinical Nutrition, Attikon Hospital Identifier: NCT03997708    
Other Study ID Numbers: ΕΒΔ435/19-06-2018
First Posted: June 25, 2019    Key Record Dates
Last Update Posted: December 18, 2019
Last Verified: December 2019
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: Yes
Plan Description: After the completion of the study, please contact with the research team for more information.
Supporting Materials: Study Protocol
Statistical Analysis Plan (SAP)
Informed Consent Form (ICF)
Time Frame: After the study is published.
Access Criteria: Not funded research with similar interest.

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Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: No
Keywords provided by Arezina Kasti, Attikon Hospital:
Quality of life
Mediterranean Diet
Clinical Nutrition
Additional relevant MeSH terms:
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Irritable Bowel Syndrome
Signs and Symptoms, Digestive
Colonic Diseases, Functional
Colonic Diseases
Intestinal Diseases
Gastrointestinal Diseases
Digestive System Diseases