Stroke prevention seems to piggyback on a heart-healthy lifestyle, Action Points

In a large cohort of health professionals, those who didn’t smoke, were lean, exercised 30 minutes or more a day, consumed no more than two alcoholic drinks a day, and ate a healthy diet had about an 80% reduced risk of ischemic stroke compared with those who didn’t meet any of those criteria (P<0.001).

The healthy lifestyle was also associated with a reduced risk of any stroke in both men (OR 0.31, 95% CI 0.19 to 0.53) and women (OR 0.21, 95% CI 0.12 to 0.36) (P<0.001 for both), Stephanie Chiuve, Sc.D., of the Harvard School of Public Health, and colleagues reported online in Circulation: Journal of the American Heart Association.

“Our results suggest that a low-risk lifestyle that is associated with a reduced risk of multiple chronic diseases, including coronary disease and diabetes, also may be beneficial in the prevention of stroke, especially ischemic stroke,” the researchers said.

Although an overall healthy lifestyle has been associated with lower risks of coronary heart disease, diabetes, and other cardiovascular conditions, less is known about its relationship with stroke risk because of potential differences in risk factors, according to the researchers.

To explore the issue, the researchers examined data from two large prospective cohort studies, the Health Professionals Follow-Up Study (43,685 men) and the Nurses’ Health Study (71,243 women).

The mean age at baseline was 50 for women and 54 for men.

All participants were free from cardiovascular disease and cancer at baseline and self-reported diet and lifestyle factors using questionnaires administered every two to four years for about 20 years.

The low-risk lifestyle was defined as not smoking, having a body mass index less than 25 kg/m2, exercising with moderate to vigorous intensity for 30 minutes or more per day, consuming a half to one drink daily for women and up to two drinks daily for men, and eating a diet emphasizing increased intake of fruits, vegetables, cereal fiber, chicken, fish, nuts, and legumes, reduced intake of trans and saturated fats, and the use of a multivitamin for at least five years.

During follow-up there were 1,559 strokes (853 ischemic) among women and 994 (600 ischemic) among men.

Among both genders, smoking, exercise, diet, and BMI were significantly associated with risk of any stroke and ischemic stroke.

Alcohol consumption was also associated significantly with stroke risk; light drinkers had a reduced risk and heavy drinkers had a greater risk.

“Moderate alcohol may be considered part of a healthy lifestyle for overall chronic disease prevention, including stroke, when consumed responsibly and not contraindicated by other factors,” the researchers said.

Midlife or baseline BMI was more strongly associated with stroke risk than that measured closest to the stroke.

“The association between obesity and risk of chronic disease is complicated and can be obscured by a reduction in body weight as a result of preclinical or chronic disease,” the researchers said.

BMI measured during midlife may be less influenced by underlying disease processes, they said.

Women who met all five criteria for a healthy lifestyle had an 81% reduced risk of ischemic stroke (OR 0.19, 95% CI 0.09 to 0.40, P<0.001) compared with those who met none.

Likewise, men who had a healthy lifestyle had an 80% reduced risk (OR 0.20, 95% CI 0.10 to 0.42, P<0.001).

Among women, 47% (95% CI 18% to 69%) of total strokes and 54% (95% CI 15% to 78%) of ischemic strokes were attributed to not adhering to the healthy lifestyle.

Among men, the percentages were 35% (95% CI 7% to 58%) and 52% (95% CI 19% to 75%).

The authors acknowledged that the study was limited by the self-reported data and possible residual confounding.

In addition, they said, because the study participants - health professionals - were likely to be healthier than the general population, the burden of unhealthy behavior may have been underestimated.

"Greater benefit is likely to be gained by adherence to healthy lifestyle choices in populations with a less healthy lifestyle than in these populations of health professionals," they said.

Primary source: Circulation: Journal of the American Heart Association
Source reference:
Chiuve S, et al “Primary prevention of stroke by healthy lifestyle” Circulation 2008; DOI: 10.1161/CIRCULATIONAHA.108.781062.