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/m2) 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.