Cholesterol-lowering drugs can reduce the number of strokes by a third and should be included in international guidelines on treating a health problem that kills millions of people each year, scientists said on Friday.
Statin drugs are usually prescribed for people at risk of having a heart attack or coronary disease, but a study of 20,000 patients has shown they could also help patients who have a higher risk of suffering a stroke, regardless of their cholesterol levels.
"This study shows that statin therapy rapidly reduces the incidence, not only of heart attacks but also of ischaemic strokes, with no adverse effect on haemorrhagic strokes," said Professor Rory Collins, lead investigator of the Heart Protection Study.
In 2002, an estimated 5.5 million people world-wide died of stroke, according to the World Health Organisation. Ischaemic stroke, which is caused by artery blockage in the brain, is more common than haemorrhagic which results from bleeding in the brain.
Collins, of the Radcliffe Infirmary in Oxford, England, said statins could help anyone who has low cholesterol levels but a high stroke risk or people who have already had a stroke.
Patients in the five-year study reported in The Lancet medical journal received 40 milligrams a day of a statin drug or a placebo, or dummy drug.
"Even in populations like China, lowering cholesterol that isn't high by our standards will lower the risk of ischaemic stroke, which is very common, and there is no evidence of any adverse effects on stroke due to bleeding," he said in an interview.
Collins added that the results reinforce the need to change both national and international guidelines which do not include lowering cholesterol to prevent stroke.
"As a consequence, a lot of people who deal with stroke do not consider statin therapy as a way of minimising the risk of stroke," he said.
Pfizer Inc's Lipitor and Merck's Zocor are leading statins but other drug companies are developing new ones.