Subtract Cigarettes, Add Years

It's never too late. That's the message Duke and American Cancer Society researchers have for smokers who think they've got nothing to gain by kicking the habit. A new study shows that even sixty-five-year-old, lifelong cigarette smokers can add a few years to their lives by quitting.

"If you smoke, you should quit regardless of your age, the earlier the better. But even for people who are sixty-five, there is reason to stop smoking: There's a benefit of gaining a year and a half to nearly four years of additional life," says the study's author, Donald H. Taylor Jr., an assistant research professor of public policy at Duke's Center for Health Policy, Law, and Management, a part of the Terry Sanford Institute of Public Policy.

The study, covered in the June issue of American Journal of Public Health, was funded by the National Institute on Aging. It analyzed fifteen years of data from the Cancer Prevention Study II. Because those data were drawn from a large, national sample, researchers were able to identify precisely the negative effect on life span for smokers who had quit for various periods and compare that with people who never smoked or smoked until death. The researchers then projected life expectancies for smokers who quit and found that the tangible benefits of smoking cessation extended across all age ranges, even to senior citizens.

"Quitting earlier had clear advantages in terms of average life-years saved relative to continuing to smoke," Taylor says. "If someone quits smoking by thirty-five, they can really avoid most of the reduction of life span."

Men who stopped smoking by age thirty-five added 6.9 to 8.5 years to their lives and women added 6.1 to 7.7 years, compared to those who continued to smoke. Quitting at age forty-five can extend life 5.6 to 7.1 years for men, and 5.6 to 7.2 years for women, the study showed. Men who put down cigarettes at fifty-five can buy themselves an additional 3.4 to 4.8 years, women 4.2 to 5.6 years. Even men who stop smoking at sixty-five can count on living 1.4 to two years longer than they would if they kept puffing; women gain 2.7 to 3.7 years.

Most studies have presented the benefits of smoking cessation in terms of reduction of health risks, such as lowering the chance of heart disease or lung cancer. The new study may provide new fodder for health-care providers who want to encourage patients to stop smoking. Says Taylor, "We hope that representing the benefits of stopping smoking in years added to life is more understandable to smokers, and will encourage them to quit."