Inappropriate intensification of glucose-lowering treatment in older patients with type 2 diabetes: the global DISCOVER study

Abstract

Introduction: Although individualized target glycated hemoglobin (HbA_1c) levels are recommended in older people with type 2 diabetes, studies report high levels of potential overtreatment. We aimed to investigate the proportion of older patients (aged ≥65 years) who potentially received an inappropriately intensive treatment (HbA_1c level <7.0% (53.0 mmol/mol)) in a global study. Factors associated with intensive glycemic management and using glucose-lowering medications associated with a high risk of hypoglycemia (high-risk medications (insulin, sulfonylureas, and meglitinides)) were also assessed.

Research design and methods: DISCOVER is a 3-year observational study program of 15 992 people with type 2 diabetes initiating second-line glucose-lowering therapy in 38 countries. Data were collected at baseline (initiation of second-line therapy) and at 6, 12, and 24 months. Factors associated with an inappropriately intensive treatment or using high-risk medications were assessed using a hierarchical regression model.

Results: Of the 3344 older patients with baseline HbA_1c data in our analytic cohort, 23.5% received inappropriate treatment intensification. Among those who had follow-up HbA_1c data, 55.2%, 54.2%, and 53.5% were inappropriately tightly controlled at 6, 12, and 24 months, respectively, with higher proportions in high-income than in middle-income countries. The proportion of patients receiving high-risk medications was higher in middle-income countries than in high-income countries. Gross national income (per US$5000 increment) was associated with increased odds of inappropriately intensive treatment but with decreased odds of receiving high-risk medications.

Conclusions: A large proportion of older DISCOVER patients received an inappropriately intensive glucose-lowering treatment across the 2 years of follow-up, with substantial regional variation. The use of high-risk medications in these patients is particularly concerning.

Keywords: diabetes mellitus; disease management; observational study; type 2.