Trends in ischaemic heart disease in the Hunter Region of New South Wales 1985-1989

Abstract

Objective: To find out whether trends in rates of non-fatal myocardial infarction (MI) parallel trends in rates of coronary death.

Design: A population-based observational study involving continuous surveillance of all suspected heart attacks or coronary deaths from 1985 to 1989.

Study population: Residents of the Hunter Region of New South Wales aged under 70 years.

Main outcome measures: Rates of non-fatal definite or possible MI or fatal MI or coronary death, as defined by the diagnostic criteria of the WHO MONICA Project.

Results: For men, mortality rates declined by an average of 16.2 per 100,000 per year (95% confidence interval [CI]: -23.8, -8.7); rates of non-fatal definite MI declined by 16.2 per 100,000 (95% CI: -27.8, -4.6); rates of non-fatal possible MI increased initially and then stabilised. For women smaller changes occurred in the same directions.

Conclusion: In this population trends in rates for non-fatal definite MI paralleled the declines in mortality rates. Rates for less severe non-fatal possible MI did not follow this pattern, perhaps reflecting increased medical attention to chest pain.