Just because a health plan will pay for smokers to try to quit doesn't mean they will, according to a new study.

SMOKING Interactive: Cigarette Chemicals Survey: Best Way To Quit? FROM OUR PARTNERS Help: Quit Smoking For Good Calculate: Cost Of Smoking Health: Smoking Complications Addiction: Nicotine Dependence

When two Minnesota health plans -- Blue Cross Blue Shield and HealthPartners -- decided in 1999 to cover the cost of antismoking drugs like bupropion and nicotine patches, researchers recruited more than 2,300 volunteers inside and outside those plans to see what would happen.

"Smokers with the benefit were no more likely to quit than were smokers without the benefit," said Raymond G. Boyle, a research investigator with HealthPartners, in an article in the November-December edition of the journal Health Affairs.

Despite recommendations from the federal government that insurers should cover smoking-cessation services, "After 12 months, the presence of the benefit was not associated with any change in use of bupropion, nicotine patches or nicotine gum," the researchers wrote. "In addition, the smoking-cessation benefit had no significant effect on attempts to quit smoking or actual quitting."

Previous studies have found that bupropion -- known as Zyban -- and the nicotine-replacement patches and gum are effective in getting smokers to quit, and many doctors are prescribing them with positive effect. Smoking cessation also includes counseling and other behavior-change therapies.

This study found that after one year of benefit coverage, only 30 percent of smokers were aware of that coverage. Furthermore, 6 percent of those who were not covered mistakenly thought they were.

The researchers said they saw no change in how physicians approached quit-smoking therapy after introduction of the benefit.

"Because smokers had to obtain a prescription to use the benefit, the very limited change in physicians' behavior could help to explain why quitting attempts and rates did not change in concert with use of pharmocotherapy," they wrote.

The researchers concluded that merely providing coverage for smoking-cessation products will not substantially affect rates of smoking cessation.

"It is possible that if other types of cessation support were covered as well, or if greater efforts were made to make smoker members aware of the coverage, different results might be seen," they wrote.