Smokers must quit for 16 years to level out cardiovascular risk
Cigarette smoking is on the decline in the United States, and researchers have been quantifying the health benefits of quitting. However, new research from the American Heart Association has revealed that it takes more than 15 years for former smokers to reduce their cardiovascular disease risk to the level of those who never smoked.
Previous studies have concluded that the increased risk for cardiovascular disease among smokers diminishes just a few years after quitting. However, those studies did not account as accurately for the history of the smokers, including variations in the number of cigarettes smoked per day, or quitting followed by a relapse.
For the current investigation, the researchers obtained detailed information from 8,700 participants in the Framingham Heart Study, including lifetime smoking history. The individuals were all free of cardiovascular disease at the beginning of the study.
The participants were followed up on an average of 27 years later, when cardiovascular disease risk was compared among current, former, and non-smokers.
The study revealed that former smokers who had quit within the last five years reduced their cardiovascular disease risk by 38 percent compared to those who continued to smoke. In addition, the experts found that the risk of cardiovascular disease among former smokers did not return to the level of non-smokers for 16 years.
The researchers also determined that more than 70 percent of cardiovascular disease events in current or former smokers occurred among those who smoked at least one pack a day for 20 years.
Study co-author Meredith Duncan is a Ph.D. student at Vanderbilt University Medical Center in Nashville, Tennessee.
“These findings underscore the benefits of quitting smoking within five years, which is 38 percent lower risk of a heart attack, stroke, or other forms of cardiovascular disease risk compared to people who continue to smoke,” said Duncan. “We also found that cardiovascular disease risk remains elevated for up to 16 years for former smokers compared to people who have never smoked. The bottom line is if you smoke, now is a very good time to quit.”
The research will be presented in Chicago at the American Heart Association’s Scientific Sessions 2018.