Abstract 085: Pediatric Dyslipidemia Is Associated With Higher Urinary Angiotensin Converting Enzyme Activity And Blood Pressure Values In A Brazilian Cohort

Abstract

Angiotensin converting enzyme (ACE) upregulation in adults contributes to cardiometabolic diseases including dyslipidemia and atherosclerosis. Objective: Investigate whether ACE activity is modulated in pediatric dyslipidemia. Methods: We evaluated anthropometric measurements, blood pressure and fasting lipid concentrations of 360 individuals (190 boys and 170 girls) aged from 6 to 19 year (mean 11.6). Categorization was done according to the levels of each lipoprotein (Total cholesterol (TC), triglycerides (TG), LDL-C, HDL-C, and non-HDL) into three groups: normolipidemic, borderline and dyslipidemic; reference values were according to American Academy of Pediatrics and Brazilian Pediatric Society. ACE activity in urine was measured with the substrates Z-FHL-OH and hippuryl-HL-OH. ACE activity ratio to infer N-domain activity was calculated (Z-FHL/h-HL). Results: Dyslipidemic levels of HDL-C, TG and LDL-C were observed in 23%, 9% and 3% of the participants, respectively. These clinical alterations were more frequent in obese children (Chi-square, p <0.001). ACE activity (Z-FHL) was higher in the groups with borderline and dyslipidemic values of HDL-C than in normolipidemic group (0.077 vs 0.070 vs 0.037 nmol/min/mg of creatinine, p = 0.01). The ratio of ACE activity was augmented in HDL-C borderline group when compared to HDL-C normolipidemic group (5.06 vs 2.39, p <0.01) and in LDL-C dyslipidemic group than in LDL-C borderline and LDL-C normolipidemic groups (8.66 vs 1.84 vs 2.88, p = 0.02). Volunteers with normal levels of TG presented lower diastolic blood pressure (DBP) mmHg (p = 0.02), percentile of DBP (p < 0.01), and percentile of systolic blood pressure (SBP) (p <0.01) than volunteers with borderline and dyslipidemic levels of TG. Also, increased DBP mmHg was observed in borderline and dyslipidemic HDL-C groups when compared to normolipidic HDL-C group. Conclusion: Pediatric hypertriglyceridemia, HDL-C deficiency and high LDL-C were related to higher urinary ACE activity (mainly N-domain). ACE modulation can contribute to higher risk of hypertension and other cardiometabolic alterations still in childhood and adolescence. Also, impairment in lipoprotein levels was associated with higher blood pressure values.