Risk‐factor levels and mortality of ischaemic heart disease in three Australasian centres

Abstract

As part of the World Health Organization MONICA Study, the prevalence of cardiovascular risk factors was estimated for Auckland (1982), Perth (1983) and Newcastle (1983). Measurements of blood pressure, blood lipid levels, the prevalence of cigarette smoking, obesity and other factors were obtained by similar methods in each centre from random samples of men and women aged between 35 and 64 years whose names were drawn from the electoral rolls. These risk-factor levels were then compared with official statistics on mortality of all causes and of ischaemic heart disease for the three populations around the same time. There were substantial differences in mortality among the three centres. Death rates of all causes and of ischaemic heart disease were lowest in Perth and highest in Newcastle (except for all-causes mortality for women, which was highest in Auckland). Compared with Perth, differences in the mortality rates of ischaemic heart disease were 27% higher for men and 35% higher for women in Auckland, and 44% and 95% higher, respectively, in Newcastle. Levels of risk factors showed the same pattern for Perth (lower) and Newcastle (higher) but were somewhat inconsistent for Auckland. The relative magnitudes of the differences in risk factors were less than for the differences in mortality. Thus, other risk factors, socioeconomic differences and differences in medical care may also contribute to the differences in ischaemic heart disease mortality rates and further explanations should be sought for the large differences among these cities.