Is carotid artery evaluation necessary for primary prevention in asymptomatic high-risk patients without atherosclerotic cardiovascular disease?

OBJECTIVE: Routine measurement of the carotid intima–media thickness is not recommended in recent clinical practice guidelines for risk assessment of the first atherosclerotic cardiovascular disease (ASCVD) event (the definition of which includes acute coronary syndromes, a history of myocardial infarction, stable or unstable angina, coronary or other arterial revascularization, stroke, transient ischemic attack, or peripheral arterial disease presumed to be of atherosclerotic origin). The aim of the present study was to elucidate the role of carotid artery evaluation for primary prevention of ASCVD in asymptomatic high-risk patients visiting a teaching hospital. METHODS: Eight hundred seventy-three patients (487 male [55.8%], mean age 59.4±11.5 years) who were statin-naive and without ASCVD, which was proven by coronary angiography or coronary CT angiography, were enrolled in this study. The patients underwent carotid scanning in the Medical Department of St Mary’s Hospital from September 2003 to March 2009. ASCVD outcomes were evaluated for median follow-up of 1,402 days. RESULTS: A total of 119 participants experienced ASCVD events. In multivariate Cox regression analysis, age (hazard ratio [HR] =1.026, 95% confidence interval [CI] =1.002–1.050, P=0.033), history of smoking (HR =1.751, 95% CI =1.089–2.815, P=0.021), statin therapy (HR =0.388, 95% CI =0.205–0.734, P=0.004), and carotid plaques (HR =1.556, 95% CI =1.009–2.400, P=0.045) were associated with ASCVD events. In middle-aged group (45≤ age <65, n=473), history of smoking (HR =1.995, 95% CI =1.142–3.485, P=0.015), statin therapy (HR =0.320, 95% CI =0.131–0.780, P=0.012), and carotid plaques (HR =1.993, 95% CI =1.116–3.560, P=0.020) were associated with ASCVD events. CONCLUSION: The presence of carotid plaques, history of smoking, and statin therapy might be important factors for primary prevention of ASCVD in asymptomatic high-risk patients, especially in middle-aged patients. Therefore, the results suggest that carotid artery parameters may have an additional predictive value for primary prevention of ASCVD in the middle-aged high-risk patients.