The impact of dyslipidemia on early markers of endothelial and renal dysfunction in children

Abstract Background Dyslipidemia has been associated with endothelial dysfunction in childhood. Impairment of renal function has been demonstrated in dyslipidemic adults. Objective The aim of this study was to assess markers of early endothelial and renal dysfunction in dyslipidemic children. Methods This was a cross-sectional study of 100 children with dyslipidemia and 100 age- and sex-matched control subjects without dyslipidemia aged 7 to 16 years. Renal dysfunction was assessed by measurement of serum creatinine and cystatin C levels, urinary beta 2-microglobulin levels, urinary albumin to creatinine (Alb:Cr) ratio, and by the estimated-glomerular filtration rate (eGFR), based on serum creatinine or cystatin C. Endothelial dysfunction and early vascular changes were evaluated by ultrasound assessment of flow-mediated dilation (FMD) of the brachial artery, and carotid intima-media thickness (cIMT), respectively. Results The markers of early renal dysfunction showed no difference between the dyslipidemic children and control subjects except for the urinary Alb:Cr ratio that was higher in the dyslipidemic children (median, 0.007 mg/mg vs 0.005 mg/mg, p=0.004). The urinary Alb:Cr ratio was positively correlated with the triglyceride to high-density lipoprotein cholesterol ratio (r=0.28, p=0.013). FMD values were lower in the dyslipidemic children than in the control subjects (8.504±4.73 % vs 10.535±4.35 %, p=0.004), but cIMT did not differ between groups. This decrease in FMD values was evident in children aged ≥10 years. FMD was independently associated with the level of lipoprotein (a) (beta=-0.29, p=0.01). Conclusion Among markers of endothelial and renal dysfunction investigated, FMD was found to be lower and the urinary Alb:Cr ratio higher in children with dyslipidemia.