Objectives: To assess the incidence and case fatality rate (CFR) from acute coronary insufficiency in men among occupational categories and to analyse the relationship between these disparities and the distribution of cardiovascular risk factors in the French population.
Setting: Three registers of the WHO-MONICA project in France: the urban area of Lille and two French districts: Bas-Rhin and Haute-Garonne.
Methods: Two sets of data were used: 1) the incident cases collected by the three MONICA Collaborating Centres (MCC) of the French WHO-MONICA Project (Lille, Strasbourg and Toulouse), between 1985 and 1989; 2) a cross-sectional study on cardiovascular risk factor prevalence performed in 1985-1989 in the three areas corresponding to the MCC.
Subjects: The data concern 5133 new coronary events in men aged 30-59 and a sample of 1863 men aged 30-59.
Results: A strong relationship was observed between occupational categories and the incidence of acute myocardial infarction and coronary events as well as CFR. Both incidence and CFR were lower among senior executives. Incidence was higher among employees and workers. However, employees, as opposed to unskilled workers, did not have higher CFR. Using occupational category as a statistical unit, the incidence of first acute myocardial infarction and coronary events was associated with the prevalence of smokers in the population (r = 0.50, P = 0.06 and r = 0.61, P = 0.02). The CFR was associated with systolic blood pressure (r = 0.82, P = 0.002), and the prevalence of smokers (r = 0.65, P = 0.02). None of the measures of incidence or case fatality among categories was related to cholesterol, HDL-cholesterol or body mass index.
Conclusions: Strong differences were observed between occupational categories and the incidence of acute myocardial infarction, coronary events and CFR. These differences were found to be closely related to the social distribution of two major cardiovascular risk factors: tobacco smoking and blood pressure.