Author Insight: Stroke Risk May be Elevated Among Smokers of Mentholated Cigarettes

Nicholas T. Vozoris, MD, a clinical associate at St Michael’s Hospital in Toronto, and his colleagues found that women and nonblack individuals who smoked mentholated cigarettes had an elevated risk of stroke compared with those who smoked nonmentholated cigarettes. Image: Nicholas T. Vozoris

Smoking mentholated cigarettes may increase stroke risk in certain individuals, a study published today in the Archives of Internal Medicine suggests.

Many questions remain about the health effects of smoking mentholated vs nonmentholated cigarettes. Some evidence suggests that smoking mentholated cigarettes increases the likelihood of developing a smoking habit. Other data suggest that smokers of mentholated cigarettes may actually have a lower risk of lung cancer than smokers of nonmentholated cigarettes. But little information exists on noncancer health outcomes, so Nicholas T. Vozoris, MD, a clinical associate at St Michael’s Hospital in Toronto, and his colleagues examined data on about 5000 smokers from the 2001-2008 US National Health and Nutrition Examination Surveys to determine if cardiac health problems differed between smokers of mentholated versus nonmentholated cigarettes.

The researchers found an elevated risk of stroke among smokers of mentholated cigarettes compared with smokers of nonmentholated cigarettes, with an odds ratio of 2.25, but no differences in risk for other types of cardiovascular disease. Women and nonblack smokers in particular had a higher risk of stroke if they smoked mentholated cigarettes versus nonmentholated cigarettes (odds ratios of 3.28 and 3.48, respectively). Dr Vozoris discussed the findings with news@JAMA.

news@JAMA: You found an elevated risk of stroke among women and nonblack smokers of mentholated cigarettes but not among men or blacks. Why?

Dr Vozoris: It’s the opposite of what you would expect, because blacks smoke mentholated cigarettes more than other groups and they have higher stroke risk. Unfortunately, the study was not designed to answer why the risk of stroke was elevated in women who smoke mentholated cigarettes or why this race-based association was found. This study may be a springboard for more research on mentholated cigarettes and stroke risk.

news@JAMA: How might smoking mentholated vs nonmentholated cigarettes increase an individual’s stroke risk?

Dr Vozoris: Menthol is known to stimulate upper airway cold receptors and increase breath holding time, which could lead to more lung exposure to toxic chemicals in cigarette smoke. Menthol has also been shown to affect ciliary airway motion in a way that more particulate matter could be absorbed by the lungs.

news@JAMA: Why do you think other types of cardiovascular disease were not elevated among menthol smokers?

Dr Vozoris: That was an interesting finding. The reason for this could be mentholated cigarettes exert selective effects on the cerebrovascular system. An experiment in Turkey found that both types of cigarettes reduced coronary heart flow, but mentholated cigarettes contributed to greater carotid artery stiffening than nonmentholated cigarettes.

news@JAMA: How strong do you think this evidence is?

Dr Vozoris: I think the association is quite strong. We controlled for multiple potential confounders—age, sex, income, race, smoking quantity and duration, and even other cardiac risk factors—and yet we still found a statistically significant increase in stroke risk, particularly among women smokers.

news@jama: How would you like readers to use the findings of your study?

Dr Vozoris: Readers should not get the message that one cigarette is good and one is bad. Smoking raises a number of health risks. But there may be a case for smokers to move away from particular cigarettes to minimize their risk or for governments to take regulatory steps to ban mentholated cigarettes.

It will be interesting to see if these finding reignite the debate in the United States about regulation of mentholated cigarettes. These findings may cause a reassessment of the issue.

Categories: Stroke, Tobacco, Women's Health