Low prevalence of functional bowel disorders in Iranian population using Rome III.

Dear Editor,

The Research Institute for Gastroenterology and Liver Diseases in Shahid Beheshti Medical University (Iran) designed a cross-sectional household survey conducted from May 2006 to December 2007 in Tehran province, which aimed to find the prevalence of gastrointestinal symptoms and Functional disorders using Rome III criteria (1, 2). A total of 18180 adult persons drawn up randomly and interviewed using a valid questionnaire on the basis of Rome III (1, 2).

The study revealed low rate of Functional Bowel Disorders (FBD) among urban population of Tehran province. In all, 1.1% met the Rome III criteria for Irritable Bowel Syndrome (IBS), 2.4% for functional constipation (FC) and 10.9% of the participants had any type of FBD (2). Our findings suggest that the FBD is less common in our study population than in previous similar studies.

In two studies in Israel and one study in Canada, the prevalence of IBS was reported to be between 5.8–17.7% (3–5); In Turkey the overall prevalence of IBS was 6.3% respectively (6). In our study, the prevalence of IBS was significantly lower. A similar rate of IBS was found in a study conducted in Hong Kong among ethnic Chinese subjects with a prevalence of 4.1% (7).

To our knowledge, because patients for our study were recruited from a general population, the selection biases that might apply to studies recruiting from a specialist clinic or hospital based study populations should not arise.

Estimations may vary because of the specific questions used to establish a diagnosis of FBD (2). In addition, we remain uncertain about the ability of our study population to recall symptoms, over a 6-month period.

In conclusion our study suggests a low rate of IBS in our study population. Attention should be paid to the influence of social and cultural factors upon symptom identification, recall and reporting when conducting studies to estimate the prevalence of IBS and FBD (8).