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Diabetes Meds' Heart Risks In Focus

New research reviewing important concerns about heart-related risks of two leading diabetes drugs is prompting renewed calls for one to be pulled from the market.

As medical correspondent Dr. Emily Senay explained on The Early Show Wednesday, the drug that's received the most attention is Avandia, which is prescribed for people suffering from type 2 diabetes. It's one of a class of drugs intended to improve the body's ability to use insulin to regulate blood sugar levels.

A study published last May in the New England Journal of Medicine suggested that Avandia significantly increased the risk that a patient would suffer a heart attack. And an analysis released Wednesday in the Journal of the American Medical Association, using different methodology, comes to basically the same conclusion: Patients' risk of heart attack rises with Avandia by 42 percent, which is practically identical to the statistics in the study released in May.

That's especially significant because heart disease is the leading cause of death for people with diabetes, which magnifies any drug's potential contribution to heart risk, Senay points out. These researchers even say the Food and Drug Administration should reconsider its decision, reiterated just last month, to keep Avandia on the market.

The second drug evaluated by a study out Wednesday is Actos. Senay notes that it's in the same class of drugs as Avandia, meaning both act on genes in the body that regulate the ability to process insulin. But, Senay says, they don't act on the same sets of genes. And, she adds, that difference may account for very different results as far as heart attack risk is concerned: While research strongly suggests that Avandia raises the chances of having a heart attack, Actos appears to reduce that risk, and the risk of stroke, by about 18 percent. This result, if true, would make Actos the only diabetes drug known to help protect patients from heart attack.

The lead author of the Actos study, Dr. Michael Lincoff of the Cleveland Clinic, says other diabetes drugs either increase heart attack risk, have no effect on heart attack risk, or haven't generated enough data to permit experts to judge. Dr. Steven Nissen, also with the Cleveland Clinic, who participated in the earlier Avandia study and the current Actos research, says the two drugs appear to affect cholesterol levels differently, and that might help account for the different heart attack numbers. For the record, Avandia's manufacturer, Glaxo Smithkline issued a statement Tuesday disputing the finding that Actos and Avandia have different safety profiles.

So, where does this leave patients?

It suggests, Senay concludes, that patients with concerns about Avandia might have an alternative in the same class of drugs, though hardly a perfect one. Just last month, the FDA officially strengthened a so-called "black box" warning on the packaging for both of drugs. That warning involves not heart attack, but heart failure, which is the heart's inability to pump as much blood as the body needs. Heart failure has been an issue for these drugs for some time. So, Actos presents heart issues too though, for many patients, heart failure is a chronic and controllable condition, whereas heart attack can cause death with no warning. These and other considerations are things that patients need to sort out in detail with their doctors.

Senay cautions that people hearing of the new studies who are concerned enough to stop taking one of the two medications should speak to their doctors first. Discontinuing any drug without your doctor's knowledge and approval can cause a worsening of the condition that's being treated. Don't discontinue it until you and your doctor come up with an alternative plan, assuming an alternative is even warranted.

Also, Senay says, there are other medications patients can take for type 2 diabetes. Various prescription medications work in several different ways to control blood sugar levels in such patients. Some induce the body to produce more insulin. Others work in the digestive system, to prevent the breakdown of foods whose components contribute to excess blood sugar. Another inhibits the production of blood glucose in the liver. So there are options. Some will work better than others for certain individuals, but options do exist.