Smoking habits and their confounding effects among occupational groups in Sweden

Smoking habits among different occupational groups in Sweden were estimated from nation wide surveys of living conditions in 1977 and 1980/81. These surveys were conducted by Statistics Sweden and consist of interviews covering the Swedish population aged 16-74 years. The sample includes about 12,000 persons for each of the two investigations. The results show that those who may be exposed to excess risks in their work environment, smoke more than those in other occupational groups. Transport and manufacturing workers, miners, wood and paper workers and painters, for example, have higher rates of daily smokers than the national average. The highest rates, however, were found among the category of early retired or unemployed. These findings confirm that an appropriate evaluation of occupationally-related diseases affected by smoking must take smoking data into consideration. If smoking data are available from other sources, adjusted work-related risks could be calculated. This presumes the absence of interaction effects. Procedures are given and illustrated. The paper also discusses the declining trends in smoking habits between 1977 and 1980/81 and possible reasons for differences in smoking habits between occupations.