The findings from the INTERSTROKE study are published in The Lancet.
"Our findings suggest that ten simple risk factors are associated with the 90% of the risk of ischemic and intracerebreal hemorrhagic stroke worldwide," the study researchers conclude. "Targeted interventions that reduce blood pressure and smoking, and promote physical activity and a healthy heart, could substantially reduce the global burden of stroke."
There are two main types of stroke: an ischemic stroke occurs when blood flow to the brain is blocked; a hemorrhagic or bleeding stroke occurs when a diseased artery within the brain bursts, allowing blood to leak into the brain.
The new study compared risk factors among 3,000 people who had a stroke to those of 3,000 age- and sex-matched individuals who did not have a stroke. Study participants came from 22 countries.
The 10 risk factors that account for 90% of stroke risk are:
- History of high blood pressure
- Current Smoking
- Abdominal obesity
- Lack of physical activity
- Poor diet
- More than 30 drinks per month or binge drinking
- Ratio of blood fats known as apolipoprotein B (apo B) to apolipoprotein AI (apo AI)
- Heart disease
- Psychosocial stress/depression
While all of these risk factors were associated with an increased risk for ischemic stroke, just high blood pressure, smoking, abdominal obesity and diet increased the risk of hemorrhagic stroke, the study shows. Nine of these risk factors were also associated with heart attack in a related study on heart risks.
In an accompanying editorial, Jack V Tu, MD, PhD, of the Sunnybrook Schulich Heart Centre at the University of Toronto, writes that these important findings should help to inform stroke prevention strategies around the world and to reduce the global burden of stroke."