Surveillance of ischaemic heart disease: results from the Italian MONICA populations.

ABSTRACT

BACKGROUND: The major objectives are to report on coronary event mortality, incidence and attack rates and changes over time observed in the Italian MONICA populations and to assess if trends are consistent when different disease definitions are considered. An analysis of diagnostic agreement between clinical and MONICA categories is presented in the context of developing a model for estimating disease incidence in a population, based on currently available data. METHODS: Data were provided by the three Italian MONICA (MONItoring trends and determinants of CArdiovascular diseases) registers. The areas of Brianza and Friuli, both located in northern Italy, completed the 10-year period of registration. Data from the MONICA Latina area, located close to Rome, were limited to the first 3 years of registration. These data are used for assessing geographical differences in rates in the mid- 1980s and estimating the diagnostic agreement between International Classification of Diseases (ICD) codes and MONICA categories. Two diagnostic aggregates have been used the standard MONICA diagnostic definition for myocardial infarction (MI), which includes non-fatal definite myocardial infarction and fatal coronary events, and the coronary event definition which includes, in addition, non-fatal possible myocardial infarctions. RESULTS: From the mid-1980s to the mid-1990s, a considerable reduction in all-cause, cardiovascular and coronary mortality rates occurred in the monitored populations. Data from the MONICA registers confirm the accuracy of official reports of death rates and changes in Italy. Comparisons of time differences in attack and incidence rates of myocardial infarction and all coronary events indicate that the impact of the more severe manifestations of coronary heart diseases (fatal coronary event and acute MI) reduced during the period of observation, but when less severe events (minor myocardial infarction and angina pectoris) are considered, the overall impact of the disease on the population remained stable. CONCLUSION: Epidemiological surveillance of coronary syndromes is relevant over this time period of impressive changes in prevention and treatment. Continuing restrictions in available resources necessitate the development of simplified registration systems.