All-cause mortality returns to baseline 20 years after smokers quit.
The hazards of smoking are well known, as are the general benefits of quitting. In this prospective observational study, researchers investigated the effect of smoking and smoking cessation on overall and cause-specific mortality.
Nearly 105,000 women (age range, 30–55) in the Nurses’ Health Study were assessed at baseline and every 2 years from 1980 to 2004; during that time, 12,483 deaths occurred. All-cause mortality for current smokers, as compared with that for never-smokers, was significantly related to number of cigarettes smoked, with a hazard ratio of approximately 4 for smoking roughly two or more packs a day. Mortality in the first 5 years after quitting smoking, compared with continued smoking, declined 13% and returned to the level of never-smoking 20 years after quitting. Risk for dying from vascular disease declined to the never-smoker baseline level within 20 years, but the decline to baseline for lung cancer risk required more than 30 years. Approximately 28% of deaths among former smokers were attributable to smoking, compared with 64% among continuing smokers.
Comment: Editorialists note that half of all smokers alive today will die prematurely from smoking-related diseases. This study’s findings will help clinicians describe the benefits of quitting in greater detail than they could previously and should motivate them to be more aggressive in helping patients to quit smoking, given the early and rapid decline in mortality after quitting.
— Thomas L. Schwenk, MD
Published in Journal Watch General Medicine May 20, 2008
Kenfield SA et al. Smoking and smoking cessation in relation to mortality in women. JAMA 2008 May 7; 299:2037.