Each year, 800,000 people suffer from a stroke in the United States. But according to a new study, published in the journal The Lancet, 90 percent of these cases are preventable. An international team of researchers led by the Population Health Research Institute at McMaster University in Ontario examined people from every in continent in the world, and found a pattern emerged among stroke victims.

“[The study] confirms... ten modifiable risk factors associated with 90 percent of stroke cases in all regions, young and older and in men and women,” said the study’s lead author Dr. Martin O’Donnell, a clinical professor at the Population Health Research Institute, in a statement. ”Hypertension is the most important modifiable risk factor in all regions, and the key target in reducing the burden of stroke globally."

Stroke Risk
Countries throughout the world have a different ranking for risk factors for stroke, however high blood pressure is a share health risk. Photo courtesy of Pixabay, public domain

For the study, researchers examined the medical records of nearly 27,000 men and women of all different stages in adulthood. They calculated that if participants eliminated certain risk factors, they would lower their stroke risk tremendously. By eliminating each one of the following top 10 factors, participants could reduce their risk of stroke by 90.7 percent:

  • Hypertension (high blood pressure): 47.9 percent
  • Physical Inactivity: 35.8 percent
  • Lipids (transport cholesterol): 26.8 percent
  • Poor Diet: 23.2 percent
  • Obesity: 18.6 percent
  • Smoking: 12.4 percent
  • Heart Problems: 9.1 Percent
  • Alcohol Intake: 5.8 percent
  • Stress: 5.8 percent
  • Diabetes: 3.9 percent

According to the National Stroke Association, a stroke is a “brain attack” that can happen to anyone at any time, and results in brain cells being deprived of oxygen. However, having any one of the top 10 identified factors could put a person at an increased risk. Those who had multiple factors had an even greater risk of stroke, turning them into a ticking time bomb. Memory and muscle control are the first to go following a stroke, and more than two out of three survivors will end up with a disability. The Centers for Disease Control and Prevention report one American dies from a stroke roughly every four minutes, making it the fifth leading cause of death in the U.S.

The researchers also point out that because each of the 10 factors affect different populations in varying degrees, policies should be modified to address a particular country’s risk factors, and effectively lessen the risk of stroke throughout the world. Reducing hypertension cuts stroke risk by half, and is the most effective way to reduce risk of all the different preventive measures.

"Our findings will inform the development of global population-level interventions to reduce stroke, and how such programs may be tailored to individual regions," said the study’s co-author Dr. Salim Yusuf, director of the Population Health Research Institute at McMaster, in a statement. "This includes better health education, more affordable healthy food, avoidance of tobacco and more affordable medication for hypertension."

Source: Yusuf S, O’Donnell MJ, Xavier D, et al. Risk Factors For Ischaemic and Intracerebral Haemorrhagic Stroke in 22 Countries (the INTERSTROKE study): A Case-Control Study. The Lancet. 2016.