Secondary metformin monotherapy failure in individuals with type 2 diabetes mellitus

INTRODUCTION: To assess secondary metformin monotherapy (MM) failure in a real-world type 2 diabetes mellitus (T2DM) cohort. RESEARCH DESIGN AND METHODS: Using the IQVIA Electronic Medical Record (formerly GE Centricity) database, adults with T2DM who initiated MM between January 1, 2012 and June 30, 2016 and achieved glycemic control (hemoglobin A1c (HbA1c) <7% (53 mmol/mol); index date) were analyzed. Secondary MM failure was defined in two ways: loss of glycemic control (HbA1c ≥7% (53 mmol/mol)) and treatment change (addition or switch of antihyperglycemic agent). Multivariable logistic regression models assessed the association between secondary MM failure and sociodemographic and clinical factors. RESULTS: The analysis included 4775 patients initiating MM. 32.9% and 19.2% experienced secondary MM failure at 24 months measured as loss of glycemic control and treatment change, respectively. Multivariable logistic regression found that women (OR=1.3, 95% CI 1.1 to 1.5) compared with men, lower Charlson Comorbidity Index (CCI) (OR=0.89, 95% CI 0.86 to 0.93), and lower baseline HbA1c (OR=0.93, 95% CI 0.88 to 0.98) were associated with increased likelihood of loss of glycemic control. Lower CCI was associated with increased likelihood of treatment change (OR=0.78, 95% CI 0.75 to 0.82). CONCLUSIONS: The observed frequency of secondary MM failure underscores the importance of the American Diabetes Association’s recommendation for glycemic monitoring of at least every 6 months so that timely therapeutic adjustments can be made.