Smoking may increase spouse's stroke risk

NEW YORK (Reuters Health) - People with a husband or wife who smokes may have an elevated risk of suffering a stroke, a study published Tuesday suggests.

The good news, researchers found, is that the excess risk seems to dissipate after the smoking spouse quits.

Reporting in the American Journal of Preventive Medicine, the investigators note that while second-hand smoke is well-accepted as a risk factor for heart disease, its relationship to stroke risk has been less clear.

To study the question, the researchers used data from a national survey of married U.S. adults age 50 and up. The 16,225 participants were followed for an average of nine years.

Over that time, men and women who had never smoked but were married to a smoker were 42 percent more likely to suffer a first-time stroke than non-smokers whose spouses had also never smoked.

Stroke risk was increased by 72 percent among former smokers who were married to current smokers, a risk similar to that seen in current smokers.

"These findings indicate that spousal smoking increases stroke risk among nonsmokers and former smokers," conclude Dr. M. Maria Glymour of the Harvard School of Public Health in Boston and colleagues.

However, the results also seem to point to the benefits of kicking the smoking habit: Unlike their counterparts whose spouses still smoked, men and women who were married to a former smoker did not have a heightened stroke risk.

"The health benefits of quitting smoking," Glymour's team writes, "likely extend beyond individual smokers to affect their spouses, potentially multiplying the benefits of smoking cessation."

SOURCE: American Journal of Preventive Medicine, September 2008.