Chronic bronchitis in an elderly population.

BACKGROUND in order to describe the prevalence and prognostic implications of chronic bronchitis in individuals 65 years or older we analysed data from The Copenhagen City Heart Study. METHODS the population was studied in 1976-1978 resurveyed in 1981-1983 and 1991-1994 and followed with regard to survival for up to 12 years. Approximately 3,700 elderly participants with a mean age of 76 years were available for analyses. RESULTS the prevalence of chronic bronchitis was 13.0% in women and 18.6% in men. Multiple logistic regression yielded the following predictors for chronic bronchitis: male gender (odds ratio with 95% confidence interval = 1.1 (0.9-1.3)), previous smoking odds ratio = 1.7 (1.2-2.2), present smoking odds ratio = 2.1 (2.1-3.8), previous exposure to dusts and fumes (odds ratio = 2.2 (1.7-2.7)), chest infections in childhood (odds ratio = 2.1 (1.6-2.9)), more than 6 chest infections in previous 10 years (odds ratio = 6.2 (4.1-9.2)) and alcohol consumption of more than 3 drinks a day (odds ratio = 1.8 (1.3-2.3)). Chronic bronchitis was a significant predictor of both subsequent respiratory infections and survival. After adjustment for age, smoking and lung function, a Cox regression showed that chronic bronchitis was significantly related to mortality from all causes with a hazard ratio with 95% confidence interval = 1.3 (1.1-1.4), all benign respiratory diseases (hazard ratio = 2.0 (1.6-2.7)), obstructive lung disease (hazard ratio = 2.5 (1.7-3.6)) and lung cancer (hazard ratio = 2.0 (1.4-2.9)). CONCLUSIONS in an elderly population, chronic bronchitis is a prevalent condition with important prognostic implications.