[image_credit]REUTERS/Shannon Stapleton[/image_credit][image_caption]This year, about 55,000 more women than men in the U.S. will have a stroke.[/image_caption]
“We found that changing to a healthy lifestyle, even in your 50s, still has the potential to prevent strokes,” says Goodarz Danael, the study’s lead author and a professor of cardiovascular health at Harvard T.H. Chan School of Public Health, in a released statement.
Anything that can help reduce the risk of stroke is welcomed news. Although the incidence of stroke has declined significantly in the United States during the past two decades, it remains the country’s fifth leading cause of death and its leading cause of preventable long-term disability.
Each year, about 795,000 people in the United States have a stroke, and about 140,000 of them die as a result, according to the Centers for Disease Control and Prevention. That’s one stroke-related death every four minutes.
Women are at particular risk. This year, about 55,000 more women than men in the U.S. will have a stroke. The average age of a first stroke in women is 75 years. Among American women, stroke is the fourth leading cause of death and kills twice as many women as breast cancer.
Several lifestyle behaviors have been identified as playing an important role in stroke prevention, especially not smoking, exercising 30 minutes or more per day, gradually losing weight if overweight or obese, and making healthy food choices.
The authors of the current study — a team of researchers from Harvard Medical School, the Harvard T.H. Chan School of Public Health and the University of São Paulo Medical School in Brazil — wanted to see if adopting those particular lifestyle behaviors at midlife might help reduce women’s risk of stroke when they were older.
Their findings were published Thursday in Stroke, a journal of the American Stroke Association.
How the study was done
The data for the study came from 59,727 women who participated in the Nurses’ Health Study from 1986 to 2012 or until their death. At the start of the study, the average age of the women was 52, and none had a history of cardiovascular disease.
Every two to four years, the women filled out health questionnaires, which asked in detail about such health-related behaviors as the amount of time they spent exercising and the types of foods they ate.
During the study period, 2,349 of the women (4.7 percent) had a first stroke, of which 1,251 (2.4 percent) were ischemic, 351 (0.7 percent) were hemorrhagic and 747 were of an unknown type. (Ischemic strokes occur when an artery that delivers blood to the brain becomes blocked, while hemorrhagic ones happen when a blood vessel breaks and bleeds blood into the brain. About 87 percent of all strokes in the United States are ischemic.)
The authors of the current study then looked to see if the women who were practicing one or more of four healthy lifestyle factors at middle age had been less likely to have a stroke. They found that engaging in three nondietary behaviors — not smoking, regular exercise and gradual weight loss — was associated with a 25 percent reduction in the risk of any kind of stroke and a 36 percent reduction in the risk of ischemic stroke.
Adopting a more healthful diet — one that emphasized fish, nuts, whole grains, fruits and vegetables, less red meat and alcohol, and no processed meat —was associated with a 23 percent lower risk of stroke. The greatest association between diet and reduced stroke risk was found among the women who ate more fish and nuts and less unprocessed red meat.
The effect of the dietary changes was significant, but not as great as not smoking, increasing physical activity and maintaining a healthy weight, the study’s authors point out.
Limitations and implications
This is an observational study, so it can’t prove that lifestyle changes were the reason for the differences in stroke risk. Also, most of the study’s participants were white middle-aged women. The findings may not be applicable to men or to women from other racial and ethnic groups.
There is evidence from other studies, however, that the reductions in risk observed in this study are applicable to men.
Of course, there are many health-related reasons, other than reducing the risk of stroke, for why people should adopt a healthful lifestyle — at any age. But given the risk that stroke poses for most Americans, coupled with the fact that four of five strokes are preventable, this study’s findings should motivate everyone to take steps for a healthier lifestyle.
FMI: You can read the study, which was funded by the National Institutes of Health, in full on Stroke’s website.
