Pioglitazone and heart failure: Results from a controlled study in patients with type 2 diabetes mellitus and systolic dysfunction

Background: Thiazolidinediones are associated with fluid retention. often interpreted as worsening cardiae function, limiting their use in patients with heart failure (HF). We compared the effects of pioglitazone and glyburide on cardiac function in patients with type 2 diabetes, Systolic dysfunction, and New York Heart Association (NYHA) functional Class II/III HF. Methods and Results: Participants received pioglitazone or glyburide (--'-insulin) for 6 months in this double-blind, randomized, multicenter Study. The primary end point was time to HF,,I composite of cardiovascular mortality and hospitalization or emergency room (ER) visit for HE Secondary endpoints included echocardiographic and functional classification assessments. An earlier time to onset and higher incidence of the primary endpoint was noted with pioglitazone (13%) versus glyburide (8%) (P=.024). Hospitalization or ER visit occurred in 30 pioglitazone and 15 glyburide participants, 19 and 12 of whom, respectively, continued treatment. Cardiac mortality (5 versus 6 participants, respectively) and cardiac function, as measured by change in ventricular mass index (P =.959), ejection fraction (P =.413). or fractional shortening (P =.280), were similar between treatments. Conclusions: Pioglitazone was associated with a higher incidence of hospitalization for HF without an increase in cardiovascular mortality or worsening cardiac function (by echocardiography).