Weir DL, et al. - Using alternative exposure models, researchers re-evaluated the relationship between metformin use and heart failure (HF) exacerbation in patients with type 2 diabetes (T2D) and pre-existing HF. From a national US insurance claims database, data was analyzed for patients with T2D and incident HF. Seven thousand, six hundred twenty subjects with diabetes and incident HF were examined. The present data indicated that cumulative metformin exposure did not reduce the risk of HF exacerbation. In this patient population, use of other anti-hyperglycemic agents with proven effectiveness in patients with HF should be considered as treatment options.