Occupational risk factors for chronic respiratory disease in a New Zealand population using lifetime occupational history.

Objectives: To investigate associations between respiratory disease and occupational exposures in a New Zealand urban population, the Wellington Respiratory Survey.

Methods: Multiple regression analyses in a population sample of 1017 individuals aged 25 to 74 years with spirometry and questionnaire information, including a lifetime occupational history.

Results: Chronic bronchitis symptoms were associated with self-reported exposure to hairdressing, paint manufacturing, insecticides, welding, detergents and with ALOHA Job Exposure Matrix-assessed gases/fumes exposure. The strongest association was for hairdressing (odds ratio 6.91; 95% confidence interval: 2.02 to 23.70). Cumulative exposure to mineral dust and gases/fumes was associated with higher FEV₁% (forced expiratory volume in the first second of expiration) predicted. Analyses were limited by relatively small numbers of cases.

Conclusions: Increased risks of objectively defined respiratory disease, which have been previously documented, were not seen. Nevertheless, the study suggested increased risk of respiratory symptoms with various occupational exposures as well as likely healthy worker effect.