Thiazolidinediones in patients with type 2 diabetes mellitus and heart failure

PURPOSE: A review of the significant findings related to the use of the thiazolidinediones (TZDs) in the treatment of patients with type 2 diabetes mellitus and heart failure was conducted. SUMMARY: TZDs are antihyperglycemic medications that increase insulin sensitivity and improve the underlying defect of insulin resistance and type 2 diabetes mellitus, and they have the potential to slow or decrease the cardiovascular damage that results from these conditions. TZDs are also implicated in weight gain; however, this is accompanied by an improvement in insulin sensitivity and, therefore, its clinical significance is unclear. Edema has been well characterized in patients treated with TZDs. Edema is more common in patients treated with a TZD in combination with insulin and higher doses of TZDs. Because of the potential for fluid retention and worsening edema, clinical studies have excluded patients with New York Heart Association (NYHA) functional class III or IV heart failure. In patients at risk for heart failure or those who have NYHA functional class I or II symptoms, initiation of therapy should be at the lower dose for TZDs with close monitoring of weight gain, edema, and other signs of worsening heart failure. CONCLUSION: Current data suggest that TZDs may be used cautiously in patients with type 2 diabetes mellitus who are at risk for heart failure or who have NYHA functional class I or II heart failure. Patients with NYHA functional class III or IV heart failure should not receive TZDs.