The Incidence Rate of Inflammatory Bowel Disease in an Urban Area of Iran: A Developing Country

BACKGROUND The incidence of inflammatory bowel disease (IBD) varies among different societies. The aim of this study is to determine the incidence rate of IBD in Kerman, a city in Southeast Iran. METHODS All medical records that indicated a new diagnosis of ulcerative colitis (UC) or Crohn's disease (CD) were retrieved from the gastrointestinal endoscopy and pathology departments of 12 centers from October 2011 to September 2012. RESULTS The incidence rate of UC in Kerman was estimated at 4.98/100,000 (95% CI: 2.44-6.94). The mean age of patients was 39.4 years and male to female ratio was 0.89:1.0. UC patients had the following prevalence: cigarette smoking (30%), appendectomy (36%) and oral contraceptive (OCP) use (78.9%). The incidence rate of CD was 0.8/100,000 (95% CI: 0.6 4-1.14). The mean age at diagnosis was 33.3 years and male to female ratio was 0.5:1.0. Cigarette smoking was reported in 33.3%, appendectomy in 66.6% and OCP useing in 75% of CD patients. Rectal and distal colitis, left side colitis and extensive colitis was seen in 20 (55.4%), 12 (33.3%) and 4 (11.1%) of patients with UC, respectively. All patients with CD had large intestinal involvement and one case (16.6%) had ileocolonic disease. CONCLUSION Our study has shown that the incidence rate of both UC and CD in Kerman is lower than Western populations but it is the same as some Asian countries. Characteristics of disease involvement in this study are similar to other studies that have been conducted in Iran and elsewhere.