Irritable bowel syndrome amongst patients with chronic abdominal pain in Lagos, Nigeria: their profile and dietary associations

Abstract

Background: Irritable bowel syndrome (IBS) is a common functional gastrointestinal disorder in which bowel habits are altered in association with abdominal pain or discomfort. Reports of prevalence vary worldwide, with that of the sub-Sahara region ranging from 8% to 31% among apparently healthy subjects.

Aim: To determine the prevalence of IBS amongst patients presenting with chronic recurrent abdominal pain, their IBS sub-types and socio-demographic profile as well as their dietary habits. To determine the prevalence of small intestinal bacteria overgrowth (SIBO) in the cohort with IBS.

Subjects and Methods: Following ethical approval, 350 consecutive patients with recurrent abdominal pain who presented to the general outpatient departments of three (3) General hospitals in Lagos were evaluated for the presence of IBS, using the Rome III criteria via an interviewer administered questionnaire. 65 of them, who fulfilled the criteria, were clinically examined, with blood and fresh stool samples taken. Hydrogen breath test, after a lactulose drink, was performed and used to determine those IBS subjects with SIBO.

Results: The overall IBS prevalence was 18.6%. The IBS-subtypes were IBS-mixed (64.6%), IBS-constipatory type (24.6%) and IBS-diarrhoea type (10.8%). Most of the IBS patients (41.5%) were in the third decade of life, with a slight female preponderance (1.2: 1). Lower educational status (p=<0.001) and unskilled occupation (p=0.01) showed a statistically significant association with IBS, while there were no such associations with age, gender, religion, marital status and body mass index. Frequent consumption of bread, beans, egg, plantain,
yam, spaghetti, orange, rice, cassava and vegetables, were observed to be statistically significant in their association with IBS symptoms. The prevalence of SIBO in these IBS subjects were 75.4%.

Keywords: Functional gastrointestinal disorder, Irritable bowel syndrome, Chronic abdominal pain, Small intestinal bacterial overgrowth