Good glycaemic control, metformin use reduce fracture risk in diabetic patients

The risk of fracture is lower among patients with good glycaemic control on current metformin monotherapy than those who are untreated, reports a study. However, glycaemic control in patients receiving treatment other than metformin shows no association with fracture risk.

Patients with type 2 diabetes mellitus (T2DM) are at greater risk of low-trauma fractures, but the effect of antidiabetic medication in relation to glycaemic control on the risk of fracture remains poorly understood. To address this, a nested case-control analyses was conducted among individuals registered in the Clinical Practice Research Datalink.

The base population included patients with newly diagnosed T2DM from 1995 to 2017. Cases were patients with a low-trauma fracture after T2DM diagnosis, each of whom was matched to four controls. Exposures of interest were as follows: glycaemic control (last glycated haemoglobin [HbA1c] level before fracture) and type of diabetes treatment. Conditional logistic regression analyses were conducted, adjusting for several confounders.

A total of 8,809 patients were matched to 35,219 controls. The risk of fractures was reduced in patients receiving current metformin use and HbA1c levels <7.0 percent (adjusted odds ratio [aOR], 0.89, 95 percent confidence interval [CI], 0.83–0.96) and between 7.0–8.0 percent (aOR, 0.81, 95 percent CI, 0.73–0.90) compared with untreated participants.

However, the level of glycaemic control in patients treated with metformin plus one or two other antidiabetic drugs, or insulin (alone or in combination with other antidiabetic agent), did not correlate with the risk of fracture relative to untreated patients.