Background: Identifying plaque composition using ultrasound may aid in stratifying patients at high risk for cardiovascular disease (CVD). Calcification is an integral part of plaque progression and may contribute to plaque vulnerability. We investigated the ability of calcified carotid plaques identified using carotid ultrasound to predict cardiovascular outcomes in older adults.
Methods: Participants included 187 hypertensive and 187 normotensive adults undergoing a duplex scan to identify the presence of calcified carotid plaques. Hypertensive participants received either blood pressure treatment or placebo, and all participants were followed for incident cardiovascular events and death for a maximum of 11 years.
Results: The untreated hypertensive group was significantly associated with a higher time-to-any CVD event [relative risk (RR) 2.97, 95% confidence interval (CI) 2.03–4.35, P < 0.0001] and mortality (RR 3.11, 95% CI 1.92–5.04, P < 0.0001) when compared to the normotensive group. Participants with calcified carotid plaques had higher cardiovascular event rates (RR 6.22, 95% CI 1.97–19.6, P = 0.0018) and mortality (RR 6.30, 95% CI 1.55–25.7, P = 0.010) when compared to those without plaque. After controlling for age, male sex, blood pressure status, glucose, and IMT, the presence of calcified carotid plaques remained predictive of CVD events (RR 2.35, 95% CI 1.5–3.8, P = 0.0005) and mortality (RR 2.72, 95% CI 1.4–5.2, P = 0.0021).
Conclusion: Calcified carotid plaques may predict mortality and cardiovascular outcomes independent of traditional CVD risk factors and may serve as an additional CVD risk assessment in the elderly.
aSchool of Health Sciences, Saint Francis University, Loretto
bAllegheny Health Network, Allegheny General Hospital, Pittsburgh
cDepartment of Epidemiology, Graduate School of Public Health, University of Pittsburgh, Pennsylvania, USA
*Trina Thompson and Kelly J. Shields contributed equally to the completion of this work.
Correspondence to Kelly J. Shields, PhD, Allegheny Health Network, Allegheny General Hospital, 320 E North Ave, South Tower 8th FL, Pittsburgh, PA 15212, USA. E-mail: firstname.lastname@example.org
Abbreviations: CVA, any cerebrovascular event; BP, blood pressure; CVD, cardiovascular disease; CHS, Cardiovascular Health Study; CCA, common carotid artery; CTA, computed tomography angiography; CHF, congestive heart failure; CAC, coronary artery calcification; ICA, internal carotid arteries; IMT, intima–media thickness; MI, myocardial infarction; PAD, peripheral arterial disease; SLE, systemic lupus erythematosus; SHEP, Systolic Hypertension in the Elderly Program; TIA, transient ischemic attacks
Received 11 April, 2014
Revised 14 November, 2014
Accepted 14 November, 2014