Efficacy and Safety of Dietary Supplementation of Diamine Oxidase to Improve Symptoms in Patients With IBS

Study Overview
=================
Brief Summary
-----------------
This project is a single center, randomized, controlled clinical trial evaluating the effects of DAO enzyme dietary supplement on symptoms of irritable bowel syndrome. These participants are randomized to either a 4-week group with DAO enzyme dietary supplement or placebo. The participants are required to fill out IBS-SSS and IBS-QOL questionnaires and record their IBS symptom improvement, IBS treatment drug use, compliance and adverse reactions every evening. At the same time, the patients' diet is continuously recorded for 3 days by 24-hour diet review method in Visit 0, Visit 1 and Visit 2, respectively, to inform the patients to avoid large fluctuations in diet structure. On days 0, 14 and 28, the subjects are asked to visit the hospital offline. The staff check with the subjects in detail according to the scale and questionnaire contents, and review the general situation and questionnaire in the previous 2 weeks. On the 7th and 21st day, the staff contact the subjects online to provide guidance and remind the subjects to fill in the scale and questionnaire. In addition, oral mucosal samples, urine and feces will be collected for identifying mutations in the genetic DAO enzyme coding gene, histamine detection and 16sRNA sequencing, respectively.

Official Title
-----------------
Efficacy and Safety of Dietary Supplementation of Diamine Oxidase (DAO) to Improve Symptoms in Patients With Irritable Bowel Syndrome

Conditions
-----------------
Irritable Bowel Syndrome (IBS)

Intervention / Treatment
-----------------
* Drug: DAO supplement
* Drug: Placebo


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Age 18-65 years old; Diagnosed with IBS according to Rome IV diagnostic criteria; Recurrent abdominal pain occurred on an average of at least 1 day per week in the past 3 months and was associated with two or more of the following criteria: i. Related to defecation; ii. Associated with changes in bowel frequency; iii. Correlated with fecal morphological changes. The symptoms appeared at least 6 months before diagnosis, and the above diagnostic criteria were met in the last 3 months. Voluntarily participate in the experiment and sign the informed consent. Exclusion Criteria: Patients with endoscopy examinations which suggest chronic intestinal diseases other than IBS, such as inflammatory bowel disease, celiac disease, gastric and duodenal ulcers, parasitic or bacterial intestinal infections; Pregnant and lactating women; Patients suffering from serious concomitant diseases, such as liver disease, cardiovascular disease, lung disease, kidney disease, tumor; Alcoholism.

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: DAO supplement group<br>One tablet of the supplementary study product was taken orally before morning, lunch and dinner every day, and each tablet contained 4.2mg of dehydrated pea seedling powder. | Drug: DAO supplement<br>* One tablet of the supplementary study product is taken orally before morning, lunch and dinner every day, and each tablet contains 4.2mg of dehydrated pea seedling powder.<br>* Other names: PEA SPROUT DEHYDRATED POWDER;|
| Placebo Comparator: Placebo group<br>Placebo was orally supplemented with one tablet each day before morning, lunch and dinner, and placebo did not contain dehydrated pea seedling powder 4.2mg. | Drug: Placebo<br>* Placebo is orally supplemented with one tablet each day before morning, lunch and dinner, and placebo does not contain dehydrated pea seedling powder 4.2mg.<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| IBS-SSS | The effects of DAO enzyme dietary supplement from dehydrated pea seedling powder on IBS symptoms were evaluated by the Severity Scale of irritable bowel Syndrome (IBS-SSS) and the changes of several independent symptoms. | 4 weeks of study medication administration | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| IBS-QOL | The overall improvement of quality of life in IBS patients with DAO enzyme dietary supplement from dehydrated pea seedling powder was evaluated by the irritable bowel Syndrome Quality of Life Questionnaire (IBS-QOL). | 4 weeks of study medication administration | 
| Improvement of symptoms listed in the Rome IV diagnostic criteria for IBS | Number of days with abdominal pain in the past week; Number of days of defecation-related abdominal pain in the past week; Frequency of bowel movements; Changes in stool pattern according to the Bristol stool Classification Scale. | 4 weeks of study medication administration |