A study conducted by Dr. David Nissen of the Cleveland Clinic concluded that people taking the diabetes medication Avandia are at a 43% greater risk of heart attack than those taking a placebo or similar drugs. Now comes confirmation from the Food and Drug Administration of a similar conclusion.

Critics of GlaxoSmithKline’s Avandia say that its side effects may be associated with somewhere between 60,000 and 100,000 heart attacks, and that 20 more occur every day. GSK’s failure to warn the public about this heart attack risk has drawn pointed criticism. Some people feel that the FDA has also gone too slow and has not adequately protected consumers.

Senator Charles Grassley has asked why the FDA did not inform the public after it got this data from GSK two years ago. Sen. Grassley and officials within the agency had urged that a “black-box” warning about the heightened heart attack risk be added to Avandia’s label, but it preferred to await the results of GSK’s ongoing study (known as RECORD, acronym for Rosiglitazone Evaluated for Cardiac Outcomes and Regulation of Glycemia in Diabetes). That study will not be published until 2009 at the earliest, and in the meantime more Avandia heart attacks and deaths may occur.

More than six million people worldwide take Avandia to treat type 2 diabetes. Its U.S. sales exceeded $2.2 billion in 2006. GSK has vigorously denied the conclusions reached by Dr. Nissen and his colleagues, which are published in the current issue of the New England Journal of Medicine. However, the company’s own analysis showed that people taking Avandia are at a 31% greater risk of heart attack.