Smoking Time, Amount Boost Stroke Risk
Researchers Examine Impact of Smoking Years and Quantity of Cigarettes Smoked
Feb. 17, 2006 (Kissimmee, Fla.) -- Here's some weighty news for heavy smokers: Your risk of stroke hinges as much on how many cigarettes you puff a day as on how many years you light up, a new study shows.
"It matters both how long you smoked and how much you were smoking at the time," says researcher Sachin Agarwal, MD, MPH, a postdoctoral fellow in cardiovascular medicine at Johns Hopkins Hospital in Baltimore, Md.
A person who smokes two packs a day for 10 years, in other words, faces the same risks as a person who smokes one pack a day for 20 years, he says.
Previous studies have shown that five to 15 years after kicking the habit, former smokers' stroke risk drops to that of people who have never taken a puff. But those studies generally considered only how much time had passed and not how many packs of cigarettes a person smoked each day, he says.
"For new smokers, the message is, if you can't stop, take a good look at how much you are smoking," Agarwal tells WebMD.
Larry B. Goldstein, MD, director of the Duke Center for Cerebrovascular Medicine at Duke University in Durham, N.C., and an American Heart Association spokesman, agrees. "People who can't quit should at least smoke as little as possible," he says.
Predicting Stroke Risk
The new study, presented here at the International Stroke Conference 2006, included a total of 42 men and women; 15 of them had never lit up and 27 of them were former smokers.
The 27 former smokers had quit an average of 30 years previously. Their average smoking exposure over their lifetime was 20 pack-years, which was calculated by multiplying the number of years smoked by the number of packs smoked daily.
Then, the researchers used magnetic resonance imaging (MRI) to compare the thickness of the walls of the carotid arteries of the former smokers and the "never" smokers. Carotid arteries are important blood vessels that supply oxygenated blood to the brain. It is your carotid artery that you feel when you check your pulse at the side of your neck.