Abstention from smoking extends life and compresses morbidity: a population based study of health expectancy among smokers and never smokers in Denmark

Objective-To estimate health expectancy that is, the average lifetime in good health-among never smokers, ex-smokers, and smokers in Denmark. Design-A method suggested by Peto and colleagues in 1992 for estimating smoking attributable mortality rates was used to construct a life table for never smokers. This life table and relative risks for death for ex-smokers and smokers versus never smokers were used to estimate life tables for ex-smokers and smokers. Life tables and prevalence rates of health status were combined and health expectancy was calculated by Sullivan's method. Setting The Danish adult population. Main outcome measures-The expected lifetime in self rated good health or without longstanding illness for never smokers and smokers. Results-The expected lifetime of a 20 year old man who will never begin to smoke is 56.7 years, 48.7 (95% confidence interval (Cl), 46.8 to 50.7) years of which are expected to be in self rated good health. The corresponding figures for a man who smokes heavily are 49.5 years, 36.5 (95% Cl 35.0 to 38.1) years of which are in self rated good health. A 20 year old woman who will never begin to smoke can expect to live a further 60.9 years, with 46.4 (95% Cl 44.9 to 47.8) years in self rated good health; if she is a lifelong heavy smoker, her expected lifetime is reduced to 53.8 years, 33.8 (95% Cl 31.7 to 35.9) years of which are in self rated good health. Health expectancy based on long standing illness is reduced for smokers when compared with never smokers. Conclusions-Smoking reduces the expected lifetime in good health and increases the expected lifetime in poor health.