According to a University of Manitoba study, published in the December 1998 issue of the Journal of Clinical Epidemiology, smokers who quit but go back to smoking retain better lung function than smokers who never quit. The same is true even for smokers who have tried to quit several times and failed.

Compiling and Comparing Data Author Robert P. Murray, PhD, of the University of Manitoba, Winnipeg, Canada and a team of researchers reviewed more than five years of data from the Lung Health Study Research Group, a randomized clinical trial of smoking cessation interventions that included 5,887 adult smokers with early chronic obstructive pulmonary disease.

Researchers compared 2,303 male smokers who continuously smoked during the study period with 730 male smokers, termed "intermittent quitters" who quit, but relapsed. According to the study, patients who made one or more unsuccessful attempts to quit retained better lung function than continuous smokers did. Dr. Murray concluded intermittent quitters could exhale more air after they took in deep breaths. This is called forced expiratory volume or FEV, and is an indicator of lung function.

Intermittent Smokers Show Benefit of Quitting The average rate of FEV loss (0.33 percent per year) was smallest among those who quit and avoided relapse. Intermittent quitters had an average FEV loss of 0.58 percent per year. Compared to intermittent quitters, FEV loss among continuous smokers doubled to 1.18 percent per year.

Researchers also found the difference in lung function loss between intermittent quitters and continuous smokers was associated less with differing quantities of cigarettes than it was with quitting-and-starting smoking patterns.

"The public health message from this study is that while complete smoking cessation remains the goal from a health perspective, attempts to stop smoking can also have a measurable health benefit. There is less cause for relapsed ex-smokers to be discouraged on their way to achieving complete cessation," the researchers wrote.

Don’t Be Discouraged About Relapsing One smoking cessation researcher said Dr. Murray’s study should affect the way people approach quitting smoking, according to one smoking cessation researcher. Instead of being discouraged by a relapse, would-be ex-smokers should view their relapse as a significant step toward complete nicotine abstinence, and should be encouraged by the health benefits of quitting for a time.

"If you quit and relapse, it’s not a wasted effort," said Robert A. Wise, MD, a pulmonologist and professor of medicine at Johns Hopkins School of Medicine. Dr. Wise was also an investigator in the Lung Health Study Research Group.

Evidence from the study could influence the way health insurance companies pay for smoking cessation therapy, added Dr. Wise. Instead of limiting coverage to one smoking cessation therapy per year, insurers may see the benefit of covering more than one attempt each year.

"Now they’ll see limiting coverage to one attempt is not in a patient’s best interest," Dr. Wise said.

Keep Up the Good Work Dr. Murray’s results reinforce what many clinicians have already seen in caring for patients who smoke and have obstructive pulmonary disease. "We deal a lot with patients who smoke," said Janet Boehm, a respiratory therapist and associate professor in the department of health professions at Youngstown State University. She is also the liaison to the Environmental Protection Agency (EPA) for the American Association of Respiratory Care, a trade association of respiratory therapists.

"We encourage them to quit by telling them they’ll begin to feel better almost immediately," Boehm said. She tells patients that quitting isn’t an easy task and relapse is a normal part of quitting smoking altogether. But she stresses that while quitting temporarily has its benefits, quitting permanently reduces smokers’ risk of lung cancer, a fact she knows on a personal level.