Adult Balanoposthitis Patients Have a Higher Risk of Type 2 Diabetes Mellitus: A Nationwide Population-Based Cohort Study

Background: We investigated the association between balanoposthitis and the risk of type 2 diabetes mellitus (type 2 DM) from a retrospective cohort study. Methods: From the Longitudinal Health Insurance Database (LHID) 2000, we selected male patients aged over 20 years and first diagnosed with balanoposthitis during 2000-2010. Men without balanoposthitis were also included in our analysis through frequency matching for age and index year. All participants were followed up until the diagnosis of type 2 DM. Diseases were coded in accordance with the International Classification of Diseases, Ninth Revision, Clinical Modification. Baseline comorbidity history for each participant was determined from the LHID dataset. A multivariable Cox proportional hazard regression model was established, and a Kaplan-Meier survival curve was plotted. Results: The incidence of type 2 DM was higher in the balanoposthitis cohort than in the nonbalanoposthitis cohort (14.8 vs. 5.42/1000 person-years) with a hazard ratio of 2.55 (95% confidence interval = 2.22-2.92) after adjusting for age and other comorbidities. The incidence of type 2 DM increased with age in both cohorts. Balanitis patients with hypertension, hyperlipidemia, or obesity had higher risks for type 2 DM than those without these conditions (all P < 0.05). Conclusions: Men with balanoposthitis may have a higher risk of type 2 DM in the future. Therefore, clinical physicians should pay more attention to the early evaluation and management of type 2 DM in the patients with balanoposthitis.