Predictors of carotid stenosis in older adults with and without isolated systolic hypertension

This study was designed to determine the prevalence of carotid stenosis and atherosclerosis in older adults with and without isolated systolic hypertension and to determine risk factors for carotid artery disease in these two groups. Duplex scans were performed on 187 participants of the Systolic Hypertension in the Elderly Program and on 187 normotensive control subjects. Doppler measures of blood flow velocity were used to determine the prevalence of internal carotid artery stenosis. Carotid stenosis was found in 25% of hypertensive participants but in only 7% of normotensive participants (p < 0.001). Among hypertensive participants, carotid stenosis was correlated with lower diastolic blood pressure (p = 0.022). In multivariate analysis, systolic blood pressure of > or = 160 mm Hg was the strongest predictor of carotid stenosis. Other variables independently related to stenosis were diastolic blood pressure of < 75 mm Hg (p = 0.001), alcohol use (p = 0.005), heart rate of > or = 80 beats per minute (p = 0.013), smoking (p = 0.034), high concentration of apoprotein B (p = 0.001), and low concentration of high density lipoprotein cholesterol (borderline significant, p = 0.069). Among hypertensive participants, the strongest predictor of carotid stenosis was low diastolic blood pressure. This relation persisted even after taking into account differences in pulse pressure. Isolated systolic hypertension is strongly correlated with carotid stenosis, and among those with isolated systolic hypertension low diastolic blood pressure is a marker for carotid stenosis.