TZD use appears safe in ambulatory patients with diabetes and HF

Thiazolidinediones (TZDs) do not appear to increase the risk of heart failure (HF) hospitalization and death in ambulatory patients with diabetes and HF, according to a retrospective analysis of a veterans population.

"I would use TZDs cautiously in patients with diabetes who have class I or II compensated HF," said the lead author of the study, David Aguilar, MD, assistant professor of medicine at Baylor College of Medicine in Houston, Texas. He noted that many clinicians are already using these agents in patients with diabetes and HF without evidence to support that this practice is safe.

TZD use is not recommended for patients with New York Heart Association class III or IV symptoms because they may exacerbate volume status and may worsen HF signs and symptoms.

Among 7,147 veterans with HF and diabetes who were treated in ambulatory clinics at Veterans Affairs medical centers, 818 were being treated with TZDs and 4,700 were not. These patients were the basis of the retrospective study, which had as its primary outcome the time to hospitalization for HF. The secondary outcome was time to death.

During 2-year follow-up, the rate of HF hospitalizations was not significantly different between the TZD users and non-users (16.4% vs. 15.8%, respectively).

The 2-year incidence of death was actually lower in the TZD users (20.5%) than the non-users (25.4%). TZD users tended to be younger with higher ejection fractions, and less likely to be hospitalized for HF in the 2 years preceding the study. When adjusting for these differences, "the benefit with TZD use went away but we still couldn't find a hazard," Dr. Aguilar said.

Although these data are reassuring, Dr. Aguilar said, he believes that a prospective, randomized trial of TZD use is warranted in patients with diabetes and class I or II symptoms.