"There is evidence suggesting that your exposure to secondhand smoke can increase your chances of getting heart disease. We asked if that was also true for stroke," said the study's lead author Adnan I. Qureshi M.D., professor and director of the Cerebrovascular Program in the Zeenat Qureshi Stroke Research Center at the University of Medicine and Dentistry of New Jersey in Newark.
Researchers analyzed data from 5,379 U.S. women who participated in the First National Health and Nutrition Examination Survey Epidemiologic Follow-Up Study. The researchers then recorded the women's smoking and marital status and the incidence of total stroke and ischemic stroke (a stroke caused by a blood clot blocking blood flow to the brain). Overall, 2,347 of the women were current or former smokers themselves. Of those women, 1,904 were married to smokers.
"We found that cigarette-smoking women with cigarette-smoking spouses had almost a six times higher relative risk of total stroke than cigarette-smoking women with nonsmoking spouses," he said.
The relative risk of total stroke was 5.7 times higher in cigarette-smoking women with cigarette-smoking spouses and 4.8 times higher for ischemic stroke.
Nonsmoking women married to smoking spouses did not have a significantly higher incidence of stroke compared to nonsmoking women with nonsmoking spouses. However, Qureshi said smoking spouses of nonsmoking women may avoid exposing their partners to smoke.
The findings emphasize that it is not just one's own smoking that contributes to stroke risk, but also spouses' smoking.
"If physicians are to make a real impact on reducing stroke risk among their patients, they should not only address their patients' smoking habits but also those of their spouses or partners," Qureshi said.
Co-authors are M. Fareed K. Suri, M.D.; Jawad F. Kirmani, M.D. and Afshin A. Divani, Ph.D.
Editor's note: For more information on stroke, visit the American Stroke Association Web site: strokeassociation.org.
Statements and conclusions of study authors that are published in the American Heart Association scientific journals are solely those of the study authors and do not necessarily reflect association policy or position. The American Heart Association makes no representation or warranty as to their accuracy or reliability.