Occupational exposure to dust, gases and fumes, a family history of asthma and impaired respiratory health

Objectives This study assessed the impact of occupational exposure to dust, gases, and fumes on respiratory symptoms, obstructive lung diseases, or the use of asthma medication among persons with and without a family history of asthma. Methods A population-based cohort was followed for 10 years. This study included all 1739 men and 1594 women occupationally active at the first survey. Exposure and respiratory health were assessed from questionnaires. Multiple logistic regression was used to estimate the effects in relation to occupational groups, with age, gender, and smoking habits as possible confounders, using both cross-sectional and longitudinal analyses. The susceptibility to impaired respiratory health was determined from a family history of asthma. Results A family history of asthma was reported by 27% of the men and 34% of the women. Both occupational exposure and a family history of asthma were associated with impaired respiratory health. The etiologic fractions showed that up to about 70% of the symptoms could be explained by a family history of asthma among those exposed to low levels of air pollutants, as well as among those with high exposure. However, high exposure contributed up to 35% of the symptoms both among those with and among those without a family history of asthma. The study indicates that the relative risk of occupational exposure to pollutants is similar for both persons with and those without a family history of asthma. Conclusions The relative risk for impaired respiratory health after exposure to occupational air pollutants seems to be similar for persons with and those without a susceptibility to impaired respiratory health.