Metabolic abnormalities, insulin resistance, and metabolic syndrome in children with primary hypertension.

BACKGROUND We sought to describe the prevalence of metabolic abnormalities and of metabolic syndrome (MS) and its relationship to target-organ damage in children with primary hypertension (PH). METHODS Patients included 113 children with untreated PH at a mean age of 14.6 years (range, 5 to 18 years). The control group consisted of 134 healthy children at a mean age of 13.5 years (range, 5 to 20 years). We performed a cross-sectional assessment of anthropometric and biochemical cardiovascular risk factors, homeostatic metabolic assessment (HOMA-IR), the insulin sensitivity index (ISI[0,120]), and adiponectin. RESULTS Metabolic syndrome, as defined by classic criteria, was present in 4 of 134 (3%) of controls versus 23 of 113 (20.4%) patients (P=.0001), but when PH was not taken as a criterion of MS, MS was diagnosed in 6.2% of patients (no significance). Left-ventricular hypertrophy (LVH) was found in 46 of 113 patients (40.7%), and severe LVH was found in 14 of 113 patients (12.5%). Patients with LVH had a greater body mass index, greater waist-to-hip-ratio, and greater number of parameters of metabolic syndrome (overall P<.05). Carotid (cIMT) and femoral superficial artery intima-media thicknesses correlated positively with HOMA-IR and negatively with ISI[0.120] and serum adiponectin (P<.05). The main predictor for cIMT was adiponectin (R2=0.178, beta=-0.466, P=.002). Left-ventricular hypertrophy was predicted (R2=0.332) by body mass index-standard deviation score (beta=0.551, P=.005) and HOMA-IR (beta=0.380, P=.04). CONCLUSIONS Metabolic syndrome, as defined by classic criteria, was diagnosed in 20% of children with PH, but when PH was not a criterion, MS was present in 6.2% of patients. Irrespective of the definition of MS, the applied markers of MS and insulin resistance were the main predictors of target-organ damage.