Hypertensive arteriopathy and intima-media (IMT) thickening is observed already in adolescents with primary hypertension (PH) at diagnosis. The injury of arterial wall may cause also generation of free radicals and free radicals may by itself perpetuate arterial wall injury. The aim of the study was to verify the hypothesis that children with PH are exposed to oxidative injury (Sox) due to impaired antioxidant barrier, and that markers of Sox correlate with IMT and metabolic risk factors of arteriosclerosis.
Study design: controlled, cross-sectional.
Patients: 76 children with untreated PH, aged 14.7 yrs (5-20): 23 girls, 53 boys.
Controls: 83 healthy children aged 13.4 yrs (4-23): 44 girls, 39 boys.
Methods: Sono-graphic assessment of IMT in common carotid (cIMT) and superficial femoral arteries (cIMT). Sox was assessed as thiobarbituric acid reactive substances plasma concentration (TBARS), glutathione plasma concentration (GSH) as well as, glutathione peroxidase activity (GPX) were tested to demonstrate free radical scavenger activity.
Results: PH pts had greater cIMT (p<0.0001), carotid wall cross sectional area (WCSA) (p<0.0001), fIMT (p<0.0001), lower HDL-cholesterol, apoA1/apoB than control group (p<0.05). GSH and GPX did not differ between groups but TBARS was significantly greater in PH pts (p <0.05). In control group fIMT significantly correlated with hCRP (r=0.30, p<0.01), homocysteine (r=0.3, p< 0.05), apoA1 (r=-0.2417, p<0.05), TBARS (r=0.329, p<0.01), GPX (r=-0.241, p<0.05) and with GSH (r=-0.22, p=0.05). In pts group, there were similar correlations between fIMT and hCRP (r=0.29, p<0.05), apoA1/apoB (r=-0.28, p<0.05).
Conclusions: PH pts are exposed to significantly higher Sox than controls. The significant correlations between markers of Sox and biochemical parameters suggest that hypertensive arteriopathy is an effect of complex interplay between Sox, metabolic and hemodynamic insults.