Modelling coronary heart disease mortality in Northern Ireland between 1987 and 2007: broader lessons for prevention

Aims: To quantify how much of the coronary heart disease (CHD) mortality decline in Northern Ireland between 1987 and 2007 could be attributed to medical and surgical treatments and how much to changes in population cardiovascular risk factors.

Methods and Results: The IMPACT mortality model was used to integrate data on uptake and effectiveness of cardiological treatments and risk factor trends in the Northern Ireland population between 1987 and 2007. The main data sources were official population and mortality statistics, hospital administration systems, primary care datasets, published trials and meta-analyses, clinical audits, and national surveys. Between 1987 and 2007, CHD mortality rates in Northern Ireland decreased by 52% in men and 60% in women aged 25–84 years. This resulted in 3180 fewer deaths in 2007 than expected if 1987 mortality rates had persisted. Approximately 35% of this decrease was attributed to increased uptake of treatments in individuals and 60% to population risk factor reductions (principally blood pressure, total cholesterol, and smoking); however, these reductions were partially offset by adverse trends in diabetes, physical inactivity, and obesity.

Conclusion: Approximately 60% of the substantial CHD mortality decline in Northern Ireland between 1987 and 2007 was attributable to major cardiovascular risk factor changes and approximately 35% was attributable to treatments. However, adverse trends in diabetes, obesity, and physical inactivity are of major concern.