Glucose metabolism in patients with essential hypertension

Purpose: Arterial hypertension is an insulin-resistant condition that has been associated with an increased incidence of diabetes. We assessed the prevalence of glucose abnormalities in a population of patients with essential hypertension. Methods: In this cross-sectional study, 420 consecutively referred essential hypertensive patients were studied at 16 hypertension clinics in university and community hospitals of Spain. Fasting and 2-hour plasma glucose and insulin levels were determined in nondiabetic patients. Results: An abnormal glucose metabolism was diagnosed in 68.5% (95% confidence interval [CI], 63.7%-72.9%) of the patients. Isolated insulin resistance, defined by a homeostasis model assessment-estimated insulin resistance (HOMA-IR) equal to or above 3.8, was shown in 9.3% (95% CI, 6.7%-12.5%); impaired fasting glucose in 11.2% (95% CI, 8.6%-14.7%); impaired glucose tolerance in 22.5% ( 95% CI, 18.5%-26.9%); silent undiagnosed type 2 diabetes in 11.5% (95% CI, 8.6%-14.5%); and known diabetes mellitus in 13.9% (95% CI, 10.4%-17.2%) of the patients. According to the European Group for the Study of Insulin Resistance and the Adult Treatment Program III criteria, the metabolic syndrome was diagnosed in 41.5% (95% CI, 35.9%-47.3%) and 47.9% (95% CI, 43.1%-52.8%) of the patients, respectively. The prevalence of left ventricular hypertrophy (defined by a left ventricular mass index [LVMI] >125 g/m(2)) was 44.2%. The relation between HOMA-IR and LVMI was statistically nonsignificant, and the LVMI values in the HOMA-IR quartiles were similar. Only 27 patients (6.4%) showed good control of cardiovascular risk factors. In most patients (273, 65%; 95% CI, 60.3%-69.4%) 2 or more cardiovascular risk factors were identified as not being under control. Conclusions: Two thirds of the patients attending hypertension clinics with essential hypertension show an abnormal glucose metabolism. The metabolic syndrome can be identified in a substantial number of these patients, and 2 or more cardiovascular risk factors are not controlled in the majority of patients. (C) 2006 Elsevier Inc. All rights reserved.