Physical and psychosocial working conditions as explanations for occupational class inequalities in self-rated health

Abstract

Socio-economic health inequalities are well documented, but efforts to explain health inequalities are less. However, previous studies suggest that working conditions provide potential explanations for inequalities in health. Cross-sectional questionnaire survey data, collected from municipal employees of the City of Helsinki, aged 40-60 years (n = 8960, response rate 67%) in 2000-02, were examined using binomial regression analysis. Socio-economic position was measured by six occupational social classes ranging from top managers to manual workers, and the outcome was self-rated health (SRH). Key physical and psychosocial working conditions and work arrangements were included as explanatory factors for inequalities in health. Occupational class inequalities in SRH were clear among women [prevalence ratio (PR) 1.89, 95% confidence interval (CI) 1.54-2.32] and men (PR 1.78, 95% CI 1.40-2.25). Heavy physical workload explained a half of the health inequalities among women and almost one-third among men. Physical and chemical exposures at work explained one-fifth of the health inequalities among women and a half among men. Job control explained 24% of the men's and 40% of women's inequalities, whereas job demands widened the inequalities by 13-14%. The effects of shift work and working hours were negligible. In the fully adjusted model, 60% of the women's and 32% of the men's inequalities in SRH were explained. Physical working conditions explained a large part and job control, a somewhat smaller part of socio-economic inequalities in SRH. Improving physical working conditions and increasing job control provide potential routes to reduced inequalities in health among employees.