Social and occupational differences in chronic obstructive lung disease in Denmark 1981-1993

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a common crippling disorder related to exposure to noxious dust and fumes. The purpose of this study was to estimate relative rates of COPD in socioeconomic groups and in 'classic' high-risk industries. METHODS: Cohorts of all gainfully employed 20-59 year old Danes in the years 1981, 1986, and 1991 were formed, to compare standardized hospitalization ratios (SHR) and time trends (1981-93). RESULTS: The risk ratio (RR) between unskilled workers and senior salaried staff was 2.31, (95% CI 2.13-2.51) for men and 1.62 (1.38-1.92) for women. Among classic high-risk occupations we found a decreasing SHR in farmers and an increasing SHR in the hotel and restaurant industry and for taxi and bus drivers. The study confirmed earlier reports on high risks in the metal, rubber, and bakery industries. CONCLUSIONS: Apart from the reduced SHR among farmers there were no signs of decreasing differences in COPD risk.