Use of glucose-lowering drugs and risk of fracture in patients with type 2 diabetes.

BACKGROUND: Diabetes mellitus is associated with an increased risk of hip fracture. The aim of this cohort study was to investigate whether glucose-lowering drugs influence the risk of hip fracture in patients with incident diabetes.

METHODS: A study was performed on a cohort of patients with incident type 2 diabetes. Diabetes diagnosis was defined using information from the Danish National Patient Registry and reimbursement information of glucose-lowering drugs from the Register of Medicinal Product Statistics. The period of observation was from 01.01.1996 till 31.12.2011. The primary exposure was glucose-lowering drugs and the primary endpoint was hip fracture. Unadjusted, adjusted, and propensity score adjusted Cox regressions were performed.

RESULTS: 5244 patients with type 2 diabetes with a mean follow up of 5.5years were included in the study. Use of sulphonylureas within the last 90days was associated with hip fracture in patients with type 2 diabetes, hazard ratio 1.64 (95% confidence interval: 1.54,1.75), whereas ever use of sulohonylyreas was not associated with an increased risk of fractures. Use of sulphonylureas within the last 90days was also associated with an increased risk of fractures at other sites. Use of glitazones within the last 90days was associated with an increased risk of hip fracture, hazard ratio 2.07 (95% confidence interval: 1.39,3.07), whereas ever use was not associated with an increased risk.

CONCLUSIONS: Current use of sulphonylureas was associated with hip fracture in patients with type 2 diabetes. Speculatively, this may be due to hypoglycemia resulting in falls.