Women Who Quit Smoking Live Longer

The life expectancy of women who quit smoking was dramatically increased compared with those women who continue smoking, a study found, confirming the benefits of smoking cessation in women.

"Even cessation at about 50 years of age avoids at least two-thirds of the continuing smoker's excess mortality in later middle age," researchers from the University of Oxford in England wrote.

In the Million Women Study, comprised of 1.3 million women in the United Kingdom enrolled between 1996 and 2001, participants completed questionnaires on their smoking habits 3 years and 8 years after their initial recruitment.  After 8 years of follow-up, 44% of participants had quit smoking. 

The women were followed up to January 1, 2011 through the United Kingdom’s national mortality records.  Of the original 1.3 million women (excluding 0.1 million with previous disease), 66,000 had died.

For 12-year mortality, those smoking at baseline showed a mortality rate of 2.76 compared with those that had never smoked.  This included the 44% that had quit smoking.  In those still smoking at the 3-year follow-up, mortality was tripled, regardless of age.   

In those participants who quit between the ages of 25 years and 45 years, respective relative risk was 1.05 for all-cause mortality.  Those who quit between the ages of 50 years and 60 years were far greater risk than earlier quitters.

"Stopping well before age 40 years would avoid well over 90% of the excess hazard in continuing smokers" but "this does not ... mean that it is safe to smoke until age 40 years and then stop," researchers concluded. 

-Michael Potts