Aspirin to prevent incident cardiovascular disease: is it causing more damage than it prevents?

Abstract

Cardiovascular disease (CVD) principally encompasses fatal and nonfatal myocardial infarction (MI) and stroke. It remains a major challenge to healthcare with a high incidence, prevalence and mortality; hence, prevention is a highly relevant topic, with many clinical implications. This editorial will briefly cover the established role of aspirin in secondary prevention, then look at why it would be expected to be less useful in primary prevention and, finally, cover the evidence for this hypothesis. There are two aspects to the prevention of CVD: primary and secondary prevention. Primary prevention refers to the reduction of incident disease in essentially healthy subjects believed to be at high risk, whereas secondary prevention refers to prevention of recurrent events in those with prevalent or established CVD. Both primary and secondary prevention involve the management of modifiable risk factors, starting with lifestyle changes (e.g., increasing exercise, improving the diet and smoking cessation). Pharmacological interventions have two different broad aims: drugs such as statins and antihypertensives focus on reducing lowdensity lipoprotein cholesterol and blood pressure, as a means of reducing the development or progression of atheroma and, hence, reducing risk of plaque rupture and a cardiovascular event. By contrast, antiplatelets such as aspirin purely target the final step in this pathway, reducing the likelihood of thrombus formation in patients with a ruptured atherosclerotic plaque. It is important to clarify that the risk profiles of individuals in the primary and secondary prevention cohorts are very different. Patients who have already had an event such as a MI (i.e., second ary prevention) have demonstrated not only that they have atherosclerotic plaque but also that, as a result of genetic predisposition and acquired risk factors, they have a tendency to form acute thrombus. It therefore makes physio logical sense that aspirin would be beneficial in this group, and this is supported Carrie-Anne Ling, Susan Unwin-Golding, Alice Wood & Kausik Ray* Editorial