Risk factors for inflammatory bowel disease: A prospective multi-center study.

INTRODUCTION: Environmental risk factors have been associated with inflammatory bowel disease (IBD). With rising incidence, it is important to know risk factors associated with IBD in our population. This study was aimed to evaluate risk factors for IBD from western India. METHODS: This was prospective, multi-center case-control study which included 1054 patients with IBD of which 765 (72.5%) were ulcerative colitis (UC) and 289 (27.4%) Crohn's disease (CD). Asymptomatic individuals without a history of any major illness served as controls. The questionnaire containing risk factors for IBD was given to patients and control group. Odds ratio and 95% confidence interval were calculated for each variable. RESULT: Significant numbers of patients with CD were from rural area. Rural environment (OR 1.071, 0.82-1.38 and OR 1.441, 1.02-2.02), higher education (OR 1.830, 1.52-2.19 and OR 1.519, 1.16-1.97), professional by occupation (OR 1.754, 1.46-2.09 and OR 1.293, 0.99-1.67), annual family income >100,000 Indian national rupees (OR 2.185, 1.52-3.13 and OR 4.648, 3.10-6.95), history of appendectomy (OR 3.158, 1.71-5.80 and OR 3.158, 1.71-5.80), and family history of IBD (OR 4.510, 2.19-9.25 and OR 3.972, 1.58-9.96) were the risk factors for UC and CD, respectively. Vegetarian diet was protective factor for UC (OR 0.29, 0.27-0.39) and risk for CD (OR 1.179, 0.88-1.57). Smoking and chronic alcoholism were not found to be the risk factors. CONCLUSION: This study highlights association between socioeconomic, dietary factors, appendectomy, and family history as risk factors for IBD.