Peptic ulcer disease, irritable bowel syndrome and constipation in two populations in Iran

To determine the prevalence of peptic ulcer disease, irritable bowel syndrome (IBS) and chronic constipation in two Iranian populations (pastoral nomads and industrial labourers) with different life styles, and to evaluate the risk factors associated with these diseases.

A total of 455 randomly selected pastoral nomads and 492 industrial labourers (all male) aged between 35-55 years.

Demographic and social data were obtained by interviews. An upper gastrointestinal tract endoscopy was performed and biopsy specimens were taken from subjects complaining of abdominal symptoms and randomly selected asymptomatic subjects. A urease test was performed on antral specimens. Serum pepsinogen I concentrations and Helicobacter pylori antibody titres were measured by radioimmunoassay and immunoglobulin (Ig) G enzyme-linked immunosorbent assay tests, respectively.

Serum pepsinogen I concentrations were similar in both nomads and industrial labourers, and the percentage with positive antibody titres for H. pylori was high in both populations (86.3 and 91% in nomads and industrial labourers, respectively). Industrial labourers were twice as likely to have duodenal ulcer (P < 0.05) than nomads. The prevalence of duodenal ulcer disease and gastric ulcer was 4.6 and 0.6% in nomads and 10.3 and 0.4% in industrial labourers, respectively. The prevalence of IBS was similar in nomads (3.1%) and industrial labourers (3.6%). Fewer nomads (1.4%) than industrial labourers (3.3%) had chronic constipation. Logistic regression analysis showed that being an industrial labourer, or smoker and having undergone previous non-gastric surgery were risk factors for duodenal ulcer disease. When the variable 'urease test' was included in the logistic regression analysis, smoking, a positive urease test and the quantity of fruit eaten per week were associated risk factors. The risk factors associated with IBS were the use of analgesics and back pain. The only risk factor associated with chronic constipation was being an industrial labourer.

Industrial labourers were twice as likely to have duodenal ulcer disease as nomads. The prevalence of IBS and chronic constipation in the two male Iranian populations was lower than that found in western countries. Duodenal ulcer disease was associated with H. pylori colonization but not with a positive serum antibody titre for H. pylori. H. pylori colonization of the antral mucosa and smoking are causative factors for duodenal ulcer disease and fruit intake is possibly an associated factor.