Proportion of community-acquired pneumonia cases attributable to tobacco smoking

Study objectives: To assess the population-attributable risk (PAR) of smoki ng and the effect of tobacco smoking on the development of community-acquir ed pneumonia (CAP) in adults, Design: A population-based case-control study, Information on history of sm oking and other risk factors was obtained by a questionnaire administered b y interview. Setting: Mixed residential-industrial area having 74,610 adult inhabitants in Barcelona, Spain. Participants: Two hundred five male and female patients (age, 15 to 74 year s old) with CAP diagnosed between 1993 and 1995, They were matched to 475; control subjects randomly selected from the municipal census. Results: Smoking any type of tobacco had an odds ratio (OR) of CAP of 2.0 f or ever smokers (95% confidence interval [CI], 1.24 to 3.24); 1.88 for curr ent smokers (95% CI, 1.11 to 3.19); and 2.14 for ex-smokers (95% CI, 1.26 t o 3.65). A positive trend for increased risk of CAP was observed for an inc rease in the duration of the habit, the average number of cigarettes smoked daily, and cumulative cigarette consumption. Former smokers had a 50% redu ction in the OR 5 years after the cessation of smoking. The risk of CAP att ributable to the consumption of any type of tobacco in this population was 32.4% of cases (95% CI, 14.8 to 50.1%). In subjects without a history of CO PD, the PAR of tobacco was 23.0% (95% CI, 3.3 to 42.7%). Conclusion: This study gives better quantitative and qualitative evidence a bout the effects of tobacco smoking on the occurrence of pneumonia in the a dult community.