Type 2 diabetes mellitus and gender-specific risk for colorectal neoplasia.

Although a positive association between type 2 diabetes mellitus (T2DM) and colorectal cancer is well established, uncertainty exists about risk differences in diabetic men and women when considering colorectal neoplasia (CN). The main objective was to examine gender-specific associations of T2DM with CN in a population-based cohort study of adults in Germany. This analysis is based on participants of the ESTHER-study, a population-based cohort study. Participants were 50-74 years old at baseline and underwent colonoscopy during 5 year follow-up. CN detected at colonoscopy were validated by medical records review. Total and gender-specific associations of T2DM at baseline and CN were estimated using log-binomial regression. Overall, 55 cases of CN were detected in 166 participants with T2DM and 328 cases in 1,360 participants without T2DM. In women, CN was found in 32 % of participants with T2DM and in 18 % without T2DM (adjusted prevalence ratio (PR): 1.66 95 % CI 1.04-2.64). In men, prevalence for CN was 35 % for those with T2DM and 33 % for those without T2DM (adjusted PR = 1.01; 95 % CI 0.71-1.43). T2DM might have a stronger impact on CN among women than among men. Further research should examine possible reasons for these differences.