Stroke Risk Higher After Heart Attack
First Month After Heart Attack Is Especially Risky, Study Shows
Dec. 5, 2005 -- After a heart attack, the odds of having a stroke are much higher than normal, researchers report.
They studied 2,160 Minnesotans who had survived a heart attack. Three key findings emerged:
- Stroke risk was 44 times higher than normal for 30 days after a heart attack.
- Stroke risk eased after the passage of time, but stayed above normal for three years after a heart attack.
- People who suffered strokes after heart attacks were particularly likely to die.
The study by Brandi Witt, MD, and colleagues appears in the Annals of Internal Medicine. Witt works at the Mayo Clinic in Rochester, Minn.
One of the researchers, cardiologist Veronique Roger, MD, MPH, of the Mayo Clinic, commented on the study in a news release.
"While our research reaffirmed the risk of stroke among patients with heart disease, the surprise was that the risk was so high in the month after a heart attack," Roger says.
"A lot of patients survive heart attacks today, which is why this study is so relevant," she continues.
Roger says the study calls attention to health risks -- including stroke -- in heart attack survivors.
After a Heart Attack
The study covered two decades of heart attack survivors in Olmstead County, Minn.
Patients had been treated for heart attacks in the county's hospitals (including the Mayo Clinic) from 1979 to 1998. They were followed for about five years, on average.
In the first 30 days after the heart attacks, patients had a stroke 44 times more than the researchers' predictions of stroke risk for the local public.
Stroke risk dropped over time. Still, it remained two to three times higher than normal for the first three years after a heart attack. After that, stroke risk dropped back down to normal, the study shows.
Most strokes seen in the study were ischemic strokes, the most common type of stroke. In an ischemic stroke, a clot blocks blood flow to the affected part of the brain.
The higher stroke risk was seen in patients throughout the study. It didn't matter if the heart attacks had happened in the late 1970s or 20 years later, the researchers report.
They note several groups that were particularly likely to have a stroke after heart attack:
- Older patients
- People with diabetes
- People who had already had a stroke
Most participants were white. The findings might not apply to people of other racial and ethnic backgrounds, the researchers write.
What Would Help?
The researchers don't draw any firm conclusions about medicines that might cut stroke risk in heart attack survivors. They didn't directly test any medications on the patients.
However, they suggest studying anticlotting drugs, though they note that those drugs raise the risk of bleeding.
In the news release, Roger mentions three ways to avoid heart disease in the first place:
- Not smoking
- Getting regular exercise
- Eating healthfully