ABSTRACT
Atheroma is the most common cause of ischaemic heart disease, stroke and peripheral vascular disease. Since these are the major causes of morbidity and mortality among adults in industrialized societies, its prevention is of great importance. An important practical distinction is made between preventive measures in healthy people (called ‘primary prevention’) and measures in people who have survived a stroke or a heart attack, or who are symptomatic, e.g. from angina or claudication (called ‘secondary prevention’). The absolute risk per unit time is greatest in those with clinical evidence of established disease, so secondary prevention is especially worthwhile (and cost-effective, since the number needed to treat to prevent a further event is lower than with primary prevention). Primary prevention inevitably involves larger populations who are at relatively low absolute risk per unit time, so interventions must be inexpensive and have a low risk of adverse effects.
