Clinical and public health significance of treatments to aid smoking cessation

There is good epidemiological evidence to show that for every continued year of smoking over the age of 40 yrs, the average smoker loses 3 months of life expectancy. Treatments to aid smoking cessation have the potential to save tens of thousands of lives annually if they: 1) lead users of those treatments to stop significantly earlier than they would otherwise have done; 2) do not undermine quitting in nonusers; and 3) are used by a significant proportion of smokers. There is strong evidence from high-quality randomised controlled trials to show that currently available treatments improve the chances of a cessation attempt succeeding permanently by between 2.5 and 10% points. For each success this brings forward quitting by an average of 25-30 yrs. Failure of a cessation attempt at 40 yrs of age costs an estimated 6-7 yrs of life expectancy. There is no evidence that introducing and publicising treatments undermines quitting in nonusers. The major factor limiting the public health benefit of treatments to aid cessation is the numbers of smokers that use them. At present, the most effective treatment combination of behavioural support plus medication is used by a very small minority of smokers. It is estimated that for every 100,000 smokers who use proven treatments to aid cessation, between 7,500 and 30,000 life-years will be saved in the future depending on the treatment. In England (UK), the use of smoking cessation treatment in 2008 is expected to save 270,000 lifeyears. A major priority for tobacco control should be finding ways of encouraging more smokers to use the most effective treatments.