LAUSR

e13036Background: This study aimed to investigate the influence of insulin therapy for type 2 diabetes mellitus (T2D) on cancer development. Methods: We evaluated 4780 patients with T2D, treated at our institution, from 1994-2006, after excluding patients with 1) preexisting cancer or cancer within 1 year after T2D registration, 2) renal transplantation, and 3) follow-up period of < 5 years. The following information was collected from the patients’ electronic medical records: age; sex; registered date of T2D and cancer; last visit; use of metformin, insulin, and medications for microvascular complications; and start date of using insulin in the first year after cohort entrance. Insulin users were stratified according to insulin start date and complication as follows: < 3 months with (462 patients) or without complications (526 patients), ≥3 months with complications (852 patients) or without complications (1249 patients). The standardized incidence ratio (SIR) was calculated using the expected age-standa...