More walking tied to lower stroke risk among men
Older men who spend several hours walking each day are less likely to have a stroke than their peers who rarely walk, a new study suggests. And walking pace didn’t seem to matter.
Researchers said few studies have looked specifically at how both walking speed and walking time or distance are linked to stroke risk.
“Stroke is a major cause of death and disability and it is important to find ways to prevent it, especially in older people who are at high stroke risk,” Barbara J. Jefferis told Reuters Health in an email. She led the research at University College London in the UK.
“Our study suggests that maintaining an active lifestyle, specifically by spending more time on all forms of walking, could be an important part of stroke prevention strategies in older people,” Jefferis said.
She and her coauthors analyzed data from men enrolled in a long-term British heart study.
The men entered the study in 1978 to 1980. In 1998 to 2000, when they were in their 60s and 70s, they filled out surveys about how often they were physically active.
The new analysis includes 2,995 men who had not had a stroke or heart disease at the time of that survey. Researchers followed them for another 11 years.
More than half of the men walked an hour or less each day. About one in six reported walking more than two hours per day.
During the follow-up period, 195 of the men had a stroke. The researchers found that the more time men spent walking, the lower their risk of stroke.
Men who walked four to seven hours each week were 11 percent less likely to have a stroke than men who walked for three hours per week or less. But that difference could have been due to chance, Jefferis and her colleagues reported in the journal Stroke.
A stronger finding was that men who walked the most - for more than three hours each day - had a two-thirds lower risk of stroke than those who spent the least time walking.
Walking pace was also tied to stroke risk, such that average-pace or brisk walkers had a 38 percent lower risk of stroke than slow walkers. But distance walked explained that finding: men who walked at an average or brisk pace also walked further than their slower peers, according to the study.
The findings don’t prove walking prevents strokes. But they could not be explained by factors known to increase a person’s risk of stroke, like age, blood pressure and cholesterol. More recently identified markers of stroke, such as proteins associated with inflammation, blood clotting or heart muscle damage also weren’t behind the link.
“What we found was that all of these factors explained only a small amount of the relationship between time spent walking and onset of stroke,” Jefferis said. “This suggests that there may be other factors operating which explain why walking protects against stroke.”
Her team’s study was funded by the National Institute for Health Research and the British Heart Foundation.
Although it only included men, Jefferis said other research has suggested walking is good for women, too.
For instance, a team of Spanish researchers reported late last year that women who walked briskly for at least three and a half hours per week had a lower risk of stroke than inactive women (see Reuters Health story of January 3, 2013 here: reut.rs/UJj2IK).
According to the Centers for Disease Control and Prevention (CDC), close to 800,000 people in the U.S. have a stroke every year, and strokes are the most common cause of serious long-term disability.
“Getting into the habit of walking every day for at least an hour could protect against stroke,” Jefferis said. That can include walking that is done while running errands, walking for leisure in a park or just walking around indoors.
Both the World Health Organization and CDC recommend adults get at least two and a half hours of moderate exercise each week.
Source: Stroke, online November 14, 2013
###
Protective Effect of Time Spent Walking on Risk of Stroke in Older Men
Older adults have the highest risks of stroke and the lowest physical activity levels. It is important to quantify how walking (the predominant form of physical activity in older age) is associated with stroke.
Methods - A total of 4252 men from a UK population-based cohort reported usual physical activity (regular walking, cycling, recreational activity, and sport) in 1998 to 2000. Nurses took fasting blood samples and made anthropometric measurements.
Results - Among 3435 ambulatory men free from cardiovascular disease and heart failure in 1998 to 2000, 195 first strokes occurred during 11-year follow-up. Men walked a median of 7 (interquartile range, 3–12) hours/wk; walking more hours was associated with lower heart rate, D-dimer, and higher forced expiratory volume in 1 second. Compared with men walking 0 to 3 hours/wk, men walking 4 to 7, 8 to 14, 15 to 21, and >22 hours had age- and region-adjusted hazard ratios (95% confidence intervals) for stroke of 0.89 (0.60–1.31), 0.63 (0.40–1.00), 0.68 (0.35–1.32), and 0.36 (0.14–0.91), respectively, P (trend)=0.006. Hazard ratios were somewhat attenuated by adjustment for established and novel risk markers (inflammatory and hemostatic markers and cardiac function [N-terminal pro-brain natriuretic peptide]) and walking pace, but linear trends remained. There was little evidence for a dose–response relationship between walking pace and stroke; comparing average pace or faster to a baseline of slow pace, the hazard ratio for stroke was 0.65 (95% confidence interval, 0.44–0.97), which was fully mediated by time spent walking.
Barbara J. Jefferis, PhD,
Peter H. Whincup, PhD,
Olia Papacosta, MSc and
S. Goya Wannamethee, PhD