Another study involving Avandia has found an increased risk of heart failure among patients taking the controversial diabetes drug. The Canadian study was published this month in the British Medical Journal.
Avandia’s cardiovascular side effects first became the subject of concern in May 2007, when an analysis of 42 clinical trails published by the Cleveland Clinic showed that patients taking the drug had a 43-percent higher risk of having a heart attack. That summer, GlaxoSmithKline and the Food & Drug Administration (FDA) came under fire for an apparent failure to warn the public about the cardiac risks associated with Avandia. In November 2007, a warning detailing Avandia’s association with myocardial ischemia was added to the drug’s boxed warning.
This latest study involved 39,494 patients, aged 66 and older, who were started on either Avandia or Actos between April 2002 and March 2008. Researchers in Toronto, Ontario found that patients treated with Actos had a 23 percent lower risk of being hospitalized for congestive heart failure, and a 14 percent lower risk of death from any cause. There was no significant difference in the risk of heart attack. During the six-year study period, 5.3 percent of patients taking Actos and 6.9 percent taking Avandia either died or were hospitalized for heart attack or congestive heart failure.
“Given the accumulating evidence of harm with rosiglitazone (Avandia) therapy and the lack of a distinct clinical advantage for the drug over pioglitazone (Actos), it is reasonable to question whether ongoing use of rosiglitazone is justified in any circumstance,” the researchers report.
The study’s principle investigator, Dr. David Juurlink, a scientist at the Institute for Clinical Evaluative Sciences in Toronto, and head of the division of clinical pharmacology and toxicology at Sunnybrook Health Sciences Centre, told the Calgary Herald that the increased risk from Avandia could be significant. “If a million patients were treated with rosiglitazone (Avandia) rather than pioglitazone (Actos), these results imply that we would see more than 8,000 excess admissions for heart failure, and more than 3,000 additional deaths from any cause,” Juurlink says.
Jurrlink also told the Calgary Herald that his practice was to never start patients on Avandia, and to switch patients on Avandia to medications that he considers to be safer.