The evolving nature of coronary artery disease

Epidemiological studies have demonstrated a substantial decline in cardiovascular mortality in industrialized countries over the last 10 years. Improvements in primary prevention and in management of acute coronary syndromes account for this decline. Despite this spectacular progress, cardiovascular disease remains the number one cause of mortality worldwide and in low- and middle-income countries. ‘Westernized’ urban lifestyle in emerging countries and the epidemic of obesity and metabolic syndrome in North America appear to be challenging this positive trend, with evidence of adverse age- and sex-adjusted mortality rates from coronary artery disease (CAD) starting to emerge. In parallel, changes in the epidemiology of CAD are being mirrored by changes in the nature of its clinical presentation. Existing randomized trials in this area have limited generalizability and our contemporary understanding of CAD is reliant on registry data. These registries have shown that cardiovascular event rates in the outpatient population with CAD are predictable and overall remain high, although a clear spectrum of risk exists. Importantly, event rates can be modified by adherence to guideline-based therapy. Consequently, optimal secondary prevention and eliminating variation in sex- and age-based patterns of investigation remain a priority. Further studies of unselected outpatient CAD populations, such as the CLARIFY registry, will help improve understanding of the prognostic determinants and inform therapeutic strategies.