Avandia's Heart Risk Higher Than Others in Its Class

But Winkelmayer believes that neither Avandia nor Actos should be used as initial treatment. When they are used, they should be used with caution, especially with patients prone to heart problems, he said.

Dr. Eric J. Topol, director of the Scripps Translational Science Institute and chief academic officer at Scripps Health in La Jolla, Calif., also thinks both drugs should be used cautiously.

"The study reinforces the heart failure risk of rosiglitazone versus pioglitazone," Topol said. "Interestingly, it doesn't show any difference in heart attack, which is the one issue that has been so controversial. So it doesn't really change things that much."

Of the two drugs, Actos appears to have a more favorable track record, Topol added. "But the possibility of cardiovascular side effects, including heart failure and heart attack, can't be forgotten."

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