[Analyzing the coronary heart disease mortality decline in a Mediterranean population: Spain 1988-2005]

Abstract

Introduction and objectives: To examine the extent to which the decrease in coronary heart disease mortality rates in Spain between 1988 and 2005 could be explained by changes in cardiovascular risk factors and by the use of medical and surgical treatments.

Methods: We used the previously validated IMPACT model to examine the contributions of exposure factors (risk factors and treatments) to the main outcome, changes in the mortality rates of death from coronary heart disease, among adults 35 to 74 years of age. Main data sources included official mortality statistics, results of longitudinal studies, national surveys, randomized controlled trials, and meta-analyses. The difference between observed and expected coronary heart disease deaths in 2005 was then partitioned between treatments and risk factors.

Results: From 1988 to 2005, the age-adjusted coronary heart disease mortality rates fell by almost 40%, resulting in 8530 fewer coronary heart disease deaths in 2005. Approximately 47% of the fall in deaths was attributed to treatments. The major treatment contributions came from initial therapy for acute coronary syndromes (11%), secondary prevention (10%), and heart failure (9%). About 50% of the fall in mortality was attributed to changes in risk factors. The largest mortality benefit came from changes in total cholesterol (about 31% of the mortality fall) and in systolic blood pressure (about 15%). However, some substantial gender differences were observed in risk factor trends with an increase in diabetes and obesity in men and an increase in smoking in young women. These generated additional deaths.

Conclusions: Approximately half of the coronary heart disease mortality fall in Spain was attributable to reductions in major risk factors, and half to evidence-based therapies. These results increase understanding of past trends and will help to inform planning for future prevention and treatment strategies in low-risk populations.