Trends in the prevalence of COPD in elderly individuals in an air-polluted city in Japan: a cross-sectional study

PURPOSE: The aim of this study was to examine the effects of exposure to air pollution and cigarette smoke on respiratory function, respiratory symptoms, and the prevalence of COPD in individuals aged ≥50 years. PATIENTS AND METHODS: We used spirometry and medical questionnaires to screen 433 individuals from Omuta City, Japan, an area with high levels of air pollution. RESULTS: Non smokers had a high estimated COPD prevalence rate of 16%. Among smokers, the estimated prevalence of COPD was 29% in seniors (50- to 74-years group) and 37% in the elderly (>75 years group). We also found a correlation between levels of suspended particulate matter and COPD. CONCLUSION: Both smoking and chronic exposure to air pollution (>5 years) decreased respiratory function, exacerbated respiratory symptoms, and increased the prevalence of COPD. We strongly recommend periodic screening for the elderly patients to facilitate early detection of respiratory disease.