Abstract

Dimensions of the demand-control psychosocial work environment model have previously been linked increased incidence of both diabetes and hypertension in Canada. However, few investigations in Canada have examined the relationship between the demand-control model and cardiovascular disease.

We linked Ontario respondents to the 2000, 2002 and 2003 cycles of the Canadian Community Health Survey, to administrative health care and hospitalisation databases to identify incident cases of cardiovascular disease over a 15 years follow-up period. Our sample included employed labour market respondents, aged 35 and older, working 15 or more hours per week, with information on the psychosocial work environment, and who were free of heart disease at baseline (n=12,358). The demand-control model was defined based on median splits (active, passive, low strain and high strain), although models using the mid-population approach and the ratio of control to demands were also examined.

Over the study period 507 incident cardiovascular events occurred. The incidence was higher among men (5.5%) compared to women (2.6%). No statistically significant differences were observed across the four different demand-control categories in the full sample. In stratified analysis, passive work environments (low control and low demands) and low-strain environments (high control and low demands) were associated with increased risk of heart disease (HR=1.94, 95% CI 0.99–3.81; HR=2.06, 95% CI 1.01–4.17), compared to active work (high demands and high control) among women. No similar relationship was observed among men.

Among a representative sample of Ontario workers, high strain work environments were not associated with increased risk of heart disease. Passive and low strain environments (both characterised by low psychological demands) were associated with increased risk of heart disease among women, but not men. Implications of these findings for assessment of the psychosocial work environment in Canada will be discussed.