Dose distribution and up-titration patterns of metformin monotherapy in patients with type 2 diabetes.

Abstract

AimsTo assess the dose distribution among users of metformin monotherapy as well as the patterns of up‐titration following initiation of therapy in people with type 2 diabetes mellitus (T2DM).Materials and MethodsThis was a retrospective cohort study of adults with T2DM in the United Kingdom (UK). Metformin dose distribution was assessed at 0, 6 and 12 months in people initiating metformin monotherapy (new users) and cross‐sectionally in people with ongoing metformin monotherapy (prevalent users). Patterns and predictors of up‐titration were also analysed in new users. Dose distributions and treatment patterns were assessed descriptively; predictors of up‐titration were determined using multivariable logistic regressions.ResultsTotals of 6174 new users and 8733 prevalent users were included. New users initiated metformin at >0 mg to ≤500 mg (25%), >500 mg to ≤1000 mg (47%), >1000 mg to ≤1500 mg (17%) or >1500 mg to ≤2000 mg (12%) daily. This distribution did not vary over time. Prevalent users of metformin received doses of >0 mg to ≤500 mg (14%), >500 mg to ≤1000 mg (40%), >1000 mg to ≤1500 mg (15%), >1500 mg to ≤2000 mg (29%) or >2000 mg (1%) daily. Among new users of metformin, 6.7% and 10.8% had been up‐titrated at 6 and 12 months, respectively, despite the majority having glycated haemoglobin >53 mmol/mol. Predictors of up‐titration included younger age and higher HbA1c.ConclusionsA majority of T2DM patients taking metformin received a dose ≤1000 mg/day. Up‐titration of metformin is infrequent in the first year postinitiation.