Another study has suggested increased risk of cardiovascular (CV) events with the diabetes drug, rosiglitazone. In the retrospective case-control study (JAMA 2007;298:2634–43), rosiglitazone was associated with an increased risk of congestive heart failure, myocardial infarction (MI) and mortality, when compared with other oral hypoglycaemic agent treatments in older patients with diabetes.
The authors, from the Institute for Clinical Evaluative Sciences, Toronto, Canada, note that most studies of CV outcomes associated with rosigllitzaone and rosiglitazone have been conducted in patients younger than 65 years. Diabetes is most common in older patients.
They analysed information on 159,026 diabetes patients (mean age 74.7 years) being treated with an oral hypoglycaemic agent from Ontario healthcare databases. The risks of congestive heart failure, MI, and death were compared between persons treated with rosiglitazone or pioglitazone and those given other oral hypoglycaemic agent combinations, after matching and adjustment for prognostic factors. Results showed that treatment with rosiglitazone but not pioglitazone was associated with a significantly increased risk of these events.
Noting that the US Food and Drug Administration has recently decided that the available data are thus far inconclusive to warrant withdrawing rosiglitazone from the market, they say that this “well-designed population-based study provides more convincing evidence that rosiglitazone is associated with an increased risk of cardiac events and deaths among elderly patients with diabetes.”
GlaxoSmithKline issued a statement saying it believes the retrospective analysis has significant limitations and generates misleading conclusions regarding MI and death. The company said: “These conclusions are inconsistent with a more robust body of evidence from large, long-term, prospective, well-designed clinical studies”.