People who have had a type of stroke caused by bleeding in the brain should avoid taking cholesterol-lowering drugs known as statins, U.S. researchers said on Monday.
Although statins are commonly used to prevent heart attacks and strokes, they said the drugs could increase the risks of a second stroke in these patients, outweighing any other heart benefits from the drugs.
"Our analysis indicates that in settings of high recurrent intracerebral hemorrhage risk, avoiding statin therapy may be preferred," Dr. Brandon Westover of Massachusetts General Hospital and Harvard Medical School and colleagues wrote in the Archives of Neurology.
That was especially true of people who had strokes in one of the brain's four lobes - frontal, parietal, temporal, or occipital - which recur more frequently than such strokes that occur deep in the brain.
Westover said people who have had this type of stroke have a 22 percent risk of a second stroke when they take statins, compared with a 14 percent risk in people who are not taking a statin.
The findings are based on a mathematical model based on data from two clinical trials.
The researchers said it is not clear how statins increase the bleeding risk in these patients. It may be having low cholesterol increases the risk of bleeding in the brain, or it may be that statins affect clotting factors in the blood that increase the risk of a brain hemorrhage in these patients.
Statins lower low-density lipoprotein or LDL, the bad kind of cholesterol that can lead to blood clots that increase the risk of heart attacks and strokes.
They are among the best-selling drugs in the world, fueled by many studies showing they reduce the risk of heart attacks and strokes.
Dr. Larry Goldstein of Duke University and Durham VA Medical Center in North Carolina said in a commentary the findings do not prove that statins increase the risk. But he said in the absence of high-quality clinical trial data, they may help doctors make better decisions about which patients with heart risks will benefit from taking statins.
Coronary heart disease is the leading cause of death in the United States, killing one in five adults.
Pfizer's Lipitor or atorvastatin has global sales of $11 billion a year while AstraZeneca's Crestor has global sales of more than $5 billion.