We sought to determine the prognostic significance of the metabolic syndrome in hypertension.
Background
Increased cardiovascular risk in hypertensive patients might be partially attributable to metabolic disturbances.
Methods
We prospectively followed for up to 10.5 years (mean 4.1 years) a total of 1,742 hypertensive patients without cardiovascular disease (55% men; blood pressure [BP] 154/95 mm Hg; age 50 ± 12 years). A modified National Cholesterol Education Program definition for metabolic syndrome was used, with body mass index in place of waist circumference.
Results
During follow-up, 162 patients developed cardiovascular events (2.28 events/100 patient-years). Event rates in the groups with one to five characteristics of the metabolic syndrome were 1.54, 1.96, 2.97, 3.35, and 5.27 per 100 patient-years, respectively (p < 0.001). A total of 593 patients (34%) had the metabolic syndrome. Patients with the syndrome had an almost double cardiovascular event rate than those without (3.23 vs. 1.76 per 100 patient-years, p < 0.001). After adjustment for age, gender, total cholesterol, creatinine, smoking, left ventricular hypertrophy, and 24-h systolic BP, the risk of developing cardiovascular events was still higher in patients with the metabolic syndrome (hazard ratio [HR] 1.73, 95% confidence interval [CI] 1.25 to 2.38). The syndrome was an independent predictor of both cardiac and cerebrovascular events (HRs 1.48 and 2.11, respectively). The adverse prognostic value of the metabolic syndrome was attenuated but still significant among the 1,637 patients without diabetes (HR 1.43, 95% CI 1.02 to 2.08).
Conclusions
In hypertensive subjects, the metabolic syndrome amplifies cardiovascular risk associated with high BP, independent of the effect of several traditional cardiovascular risk factors.
Abbreviations
ATP-III
Adult Treatment Panel III of the National Cholesterol Education Program
BMI
body mass index
BP
blood pressure
CI
confidence interval
HR
hazard ratio
LV
left ventricular
PIUMA
Progetto Ipertensione Umbria Monitoraggio Ambulatoriale