NEW YORK (Reuters Health) – Prior research has linked the thiazolidinediones pioglitazone and rosiglitazone with an increased risk of heart failure, myocardial infarction, and death, but new research shows that the former is less strongly tied to these events than the latter.

“Given that rosiglitazone lacks a distinct clinical advantage over pioglitazone, continued use of rosiglitazone may not be justified,” Dr. David N. Juurlink, from Sunnybrook Health Sciences Centre, Toronto, and colleagues state.

The findings, reported in the August 19th Online First issue of the British Medical Journal, are based on a study of 39,736 patients with type 2 diabetes in Ontario, Canada who were started on rosiglitazone or pioglitazone between 2002 and 2008. Subjects were 66 years of age or older.

During the 72-month study period, with a median follow up of roughly 292 days, 5.3% of pioglitazone-treated patients and 6.9% of those given rosiglitazone experienced the main endpoint, a composite of death or hospital admission for acute MI or heart failure.

Further analysis showed that with pioglitazone, the risks of death and heart failure were 14% and 23% lower, respectively, than with rosiglitazone. No significant difference was noted between the drugs in the rate of acute MI.

“Experience with thiazolidinediones, for which the associated risks of cardiac disease and fractures were identified only years after they were introduced on to the market, reinforces the notion that long-term studies of effectiveness and safety in clinical practice are essential to complement knowledge on efficacy gained from randomized controlled trials,” Dr. Corinne S. de Vries, from the University of Bath, UK, and Dr. David L. Russell-Jones, from the University of Surrey, Guildford, UK, write in a related editorial.

Reference:
BMJ 2009.