Much of the increased risk of death from smoking reduced within several years after quitting

May 06, 2008

Women who quit smoking significantly reduce their risk of death from coronary heart disease within 5 years and have about a 20 percent lower risk of death from smoking-related cancers within that time period, according to a study in the May 7 issue of JAMA.

“Tobacco use remains the leading preventable cause of death in the United States. Globally, approximately 5 million premature deaths were attributable to smoking in 2000. The World Health Organization projects by 2030 that tobacco-attributable deaths will annually account for 3 million deaths in industrialized countries and 7 million in developing countries,” the authors write. They add that the rate of mortality risk reduction after quitting compared with continuing to smoke is uncertain.

Stacey A. Kenfield, Sc.D., of the Harvard School of Public Health, Boston, and colleagues assessed the relationship between cigarette smoking and smoking cessation on total and cause-specific mortality in women by analyzing data from the Nurses’ Health Study, an observational study of 104,519 female participants, with follow-up from 1980 to 2004. A total of 12,483 deaths occurred in this group, 4,485 (35.9 percent) among never smokers, 3,602 (28.9 percent) among current smokers, and 4,396 (35.2 percent) among past smokers.

The researchers found a significant 13 percent reduction in the risk of all-cause mortality within the first 5 years of quitting smoking compared with continuing to smoke, and the excess risk decreased to the level of a never smoker 20 years after quitting, with some causes taking more or less time. “Significant trends were observed with increasing years since quitting for all major cause-specific outcomes. A more rapid decline in risk after quitting smoking compared with continuing to smoke was observed in the first 5 years for vascular diseases compared with other causes.”

“Much of the reduction in the excess risk for these causes of death were realized within the first 5 years for coronary heart disease and cerebrovascular disease. Sixty-one percent of the full potential benefit of quitting in regard to coronary heart disease mortality and 42 percent of the full potential benefit of quitting in regard to cerebrovascular mortality was realized within the first 5 years of quitting smoking, when comparing hazard ratios for recent quitters of less than 5 years with long-term quitters of 20 years or greater. For death due to respiratory disease, an 18 percent reduction in risk of death was observed 5 to 10 years after quitting smoking, with the risk reaching that of a never smoker’s risk after 20 years.”

For lung cancer mortality, a significant 21 percent reduction in risk was observed within the first 5 years compared with continuing smokers, but the excess risk did not disappear for 30 years. Past smokers with 20 to less than 30 years of cessation had an 87 percent reduction in risk of lung cancer mortality compared with current smokers. When including the other smoking-related cancers, the excess risk approached a never smoker’s risk more than 20 years after quitting smoking.

Significant trends were observed for earlier age at initiation of smoking for total mortality, respiratory disease mortality, and all smoking-related cancer mortality. The data also suggested that smoking is associated with an increased risk of colorectal cancer mortality but not ovarian cancer mortality. The researchers also found that approximately 64 percent of deaths among current smokers and 28 percent of deaths among former smokers were attributable to cigarette smoking.

“Early age at initiation is associated with an increased mortality risk so implementing and maintaining school tobacco prevention programs, in addition to enforcing youth access laws, are key preventive strategies. Effectively communicating risks to smokers and helping them quit successfully should be an integral part of public health programs,” the authors conclude.

Source: JAMA and Archives Journals

Explore further: Tips offered to docs, spouses for maintaining happy marriage

add to favorites email to friend print save as pdf

Related Stories

Coming up for air

Oct 29, 2014

Sometimes you've got to hit bottom to battle your way back up. In 1992, the United Nations cited Mexico City as having the worst air quality in the world, with so much pollution that birds sometimes dropped ...

The volcano of a hundred thousand mouths

Jul 02, 2014

When the 1893 World's Fair opened in Chicago, fairgoers aboard the world's first Ferris wheel soared high enough to compare two cities: the White City—gleaming whitewashed architecture built for the massive ...

Guns aren't the only things killing cops

Apr 11, 2014

The public does not realize—in fact, police themselves may not realize—that the dangers police officers are exposed to on a daily basis are far worse than anything on "Law and Order."

Recommended for you

Alcohol apps aimed at young

4 hours ago

Apps with names like 'Let's get Wasted!' and 'Drink Thin' have led a James Cook University Professor to call for Government action on alcohol advertising on mobile devices.

Proponent of the G spot takes on a critic

5 hours ago

Ashley Furin had a "very satisfying" sex life with her husband, she said. Then, seven years into their relationship, she had "an experience that rocked me to my core." They had found her G spot.

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.