Job strain and the incidence of heart diseases: A prospective community study in Quebec, Canada

Abstract

ObjectiveJob strain (high psychological demands and low decision control) is associated with cardiovascular diseases, however it remains unclear if the associations are explained by depressive symptoms, and whether there are sex differences. The objective of the present study was to evaluate the association between job strain and heart diseases in a middle-aged population-based cohort. MethodsBaseline data were from CARTaGENE, a community survey of adults aged 40–60 years in Quebec, Canada. Incidence of heart diseases was examined in 8073 individuals by linking survey data with administrative data. Cox regression models were used to examine the association between job strain and heart disease, adjusting for sociodemographic characteristics, behavioral and clinical factors, and depressive symptoms. ResultsIn total, 557 (6.9%) participants developed heart diseases over an average follow-up of 6.6 years. Job strain was associated with an increased risk of heart diseases in women (adjusted HR = 1.63, 95% CI 1.02–2.64) after controlling for depressive symptoms, behavioral and clinical factors. There was no overall association between job strain and heart diseases in men (adjusted HR = 0.96, 95% CI 0.62–1.49); an association was observed only in men aged 50 years and older. Incidence of heart diseases and high job strain was highest in those with labour jobs, and lowest in those with professional jobs. ConclusionJob strain was associated with an increased risk of heart diseases in middle-aged women and in men aged 50 years and older. This association was not accounted for by depressive symptoms or sociodemographic, clinical, and behavioral factors.