Patients with diabetes who take thiazolidinediones (TZDs) have a higher incidence of congestive heart failure (CHF) than those who do not; the incidence of CHF is similar with the use of pioglitazone (Actos), troglitazone (Rezulin), or rosiglitazone (Avandia) (strength of recommendation [SOR]: B, based on a large retrospective cohort study). However, patients on regimens that include pioglitazone but not insulin have lower rates of CHF than those taking insulin but not pioglitazone (SOR: B, based on a retrospective cohort study). Still, patients starting any TZD should be warned of the possibility of CHF and should be monitored for its development. TZDs are contraindicated for patients with class III and IV CHF (SOR: C, based on expert opinion)
