The annual death rates were 8.8 per 1000 participants in the quit-smoking program and 10.4 per 1000 in the usual care group. The annual death rates for those who actually quit was even more positive: 6.0 per 1000 patients compared with 11.0 per 1000 in those who did not quit smoking.
Overall, the death rate of those in both groups who were able to quit smoking was 46 percent lower than those who did not quit.
The study, "The Effects of a Smoking Cessation Intervention on 14.5-year Morality," is the first experimental study to show that stopping smoking adds years to life. It is published in the Feb. 15, 2005, issue of Annals of Internal Medicine.
The findings were based on data from the Lung Health Study. Randomized trials like the Lung Health Study are widely regarded as the gold standard for proof among clinical studies.
"We know that people who smoke should quit smoking," said one of the study authors, John E. Connett, PhD, professor of biostatistics of the University of Minnesota School of Public Health.
"This study showed that with very simple lung function tests -- spirometry -- we can find people who can benefit the most from an intensive quit-smoking program," Connet said. "And it not only made them healthier and feel better, it caused substantial reductions in death rate."
The participants in the study all had mild lung disease, which itself increases risk for more serious lung disease down the road.
In an editorial, "Smoking Kills, Experimental Proof from the Lung Health Study," Jonathan M. Samet, MD, MS, of the Johns Hopkins Bloomberg School of Public Health, says that the importance of the new findings is that t
Contact: Susan Anderson
American College of Physicians