Socio-occupational differences in acute myocardial infarction case-fatality and coronary care in a northern Italian population

Aims To appraise 28-day case-fatality of myocardial infarction (MI) among sociooccupational classes; to assess the consistency of the results for different degrees of MI severity; to explore if such differences are related to differences in management and treatment of the acute attack. Methods All coronary events (n = 1077), registered in 1993-1994 among the 35-64 year old male residents in MONICA Area Brianza were investigated and classified into diagnostic categories according to MONICA criteria. For an cases standardized information on acute coronary care and interventions before and during hospitalization was collected. Classification of social classes was derived from the Erikson-Goldthorpe-Portocarero social class scheme, based on information on occupational characteristics widely available in European countries. Results An increasing rate of case-fatality for decreasing levels of socio-occupational class was found. The social gradient resulted mainly from the higher incidence of out-of-hospital cardiac arrests. Treatment before and during the acute attack cannot explain the observed differences. Conclusion Combining these results with those obtained in other MONICA centres, it appears that further decreases in coronary mortality might be achieved through specific programmes addressed in particular to the reduction of out-of-hospital case-fatality in lower social classes.