Prevalence of specific variant carotid geometric patterns and incidence of cardiovascular events in older persons. The Cardiovascular Health Study (CHS E-131)

OBJECTIVES: We hypothesized that variant geometric patterns of the common carotid artery (CCA) predict the incidence of cardiovascular disease (CVD), after accounting for CCA intima-medial thickness (IMT). BACKGROUND: Common carotid artery intima-media thickness has been associated with the incidence of cardiovascular disease. METHODS: Noninvasive measurements of IMT were made with high-resolution ultrasonography in 5,640 subjects 65 years of age or older participating in the Cardiovascular Health Study. New coronary and/or cerebrovascular events served as outcome variables over a median 10.2-year follow-up. To characterize different carotid structural geometric patterns (CGP), vascular mass (VM) was combined with the wall-to-lumen ratio (W/L). Normal values for W/L and VM were defined as age-adjusted, gender-specific 75th percentiles of the 1,899 normotensive subjects free of CVD at baseline. Four CGPs were defined: CGP1 = normal W/L ratio and VM; CGP2 = arterial remodeling (i.e., increased W/L ratio with normal VM); CGP3 = arterial hypertrophy (i.e., increased W/L ratio with increased VM); and CGP4 = arterial hypertrophy with dilation (i.e., normal W/L ratio and increased VM). RESULTS: Coronary or cerebrovascular events (adjusted for age, gender, traditional risk factors, and IMT) were associated with CGP in subjects free of CVD at baseline. Specifically, the hazard ratio (Cox proportional-hazards analyses) for CGP3 (arterial hypertrophy) was 1.25 (95% confidence interval [CI] 1.03 to 1.53), and for CGP4 (arterial hypertrophy with dilation) was 1.43 (95% CI 1.16 to 1.75) compared with CGP1 (normal). CONCLUSIONS: Arterial hypertrophy defined by variant CGP patterns is associated with the development of new CVD, independent of age, traditional risk factors, and CCA IMT.