Reducing Heart Attacks and Strokes In People with Diabetes

Researchers are continually looking for better ways to control blood glucose levels as well as prevent heart attacks and strokes in people with diabetes.

Now a three-year follow-up of the PROactive study of the effect of pioglitazone (Actos) on cardiovascular events has found that the Actos-treated group had a 37 percent reduction in second heart attacks and strokes compared to placebo. Actos is an oral medication from the thiazolidinedione class used to control blood glucose levels in patients with type 2 diabetes.

These encouraging cardiac outcomes may be due to improvements in HDL cholesterol, triglycerides, and blood pressure seen with Actos in this and other studies. Actos is also known to reduce inflammation in arterial walls, another heart attack risk factor.

Interestingly, control of blood glucose did not seem to confer these heart benefits; the average HbA1c level, a measure of long-term glucose control, in the Actos group was only marginally lower than in the placebo-treated group.

Both Actos and Avandia, the other thiazolidinedione used to lower glucose levels, cause edema, an accumulation of fluid in the extremities. Since edema is also characteristic of heart failure, the concern is that these drugs may cause or worsen heart failure.

Although more patients in the Actos group than in the placebo group were hospitalized for heart failure, the authors attributed these differences to misdiagnosis of heart failure due to the edema.

Another report from the PROactive study compared Actos with a placebo in patients with type 2 diabetes who either did or did not have a prior stroke. Actos reduced the risk of a second stroke by almost 50 percent in patients with a history of a stroke; but Actos did not lower the risk of a first stroke in those with no previous history of a stroke.

These PROactive results look promising for treating people with type 2 diabetes who had a prior stroke or heart attack. But further studies are needed to validate these results.

It is worth pointing out that several long-term trials showed that statins significantly reduced the risk of a first heart attack in people with type 2 diabetes and of a first stroke in all participants in the studies.