Department of Nephrology, Kidney Transplantation & Hypertension, Children's Memorial Health Institute, Aleja Dzieci Polskich 20, 04-730 Warsaw, Poland
Prof. Dr. Ryszard Grenda
Department of Nephrology, Kidney Transplantation & Hypertension, Children's Memorial Health Institute, Aleja Dzieci Polskich 20, 04-730 Warsaw, Poland
Sonographic evaluation of arterial wall morphology and elasticity is increasingly accepted as a non-invasive tool in cardiovascular assessment. Several studies suggest that intima–media thickness (IMT) and arterial elasticity indices may sensitively reflect different vasculopathic processes in children. However, normative values and the impact of adolescent growth are largely unknown. We assessed the IMT of the common carotid (cIMT) and femoral arteries (fIMT), carotid elasticity indices and interacting anthropometric factors in 247 healthy subjects aged 10–20 years. cIMT, fIMT, incremental elastic modulus (Einc) and circumferential wall stress (CWS) were positively, and distensibility coefficient (DC) inversely, correlated with age, height, body mass index (BMI), systolic blood pressure (BP) and brachial pulse pressure (r = 0.56 to −0.45, P < 0.05 to 0.0001). DC (r = −0.29, P < 0.0001) and stiffness index β (r = 0.25, P < 0.0001), but not Einc, were significantly associated with cIMT independently of age. All vascular parameters showed non-Gaussian distributions. Excessively high IMT was associated with BMI and pulse pressure above the 90th percentile, and elevated Einc with high-normal BMI. Multivariate analysis identified independent positive effects of standardized BMI and brachial pulse pressure on normalized cIMT, negative effects of systolic BP and cIMT on DC, a positive effect of cIMT on stiffness, and positive effects of systolic BP and BMI on Einc and CWS. Morphological and functional measures of large arteries should be normalized to take account of changes during adolescence and skewed distributions. Relative body mass, systolic blood pressure and/or pulse pressure are determinants of IMT and elasticity.
1 May 2005 in Journal of the American Society of Nephrology
Increased intima-media thickness of the carotid arteries (cIMT) has been found in young adults with childhood-onset chronic kidney disease (CKD). The disease stage at which these patients first develop abnormalities of arterial texture is unknown. The objective of this study was to determine the onset and character of arterial changes in children aged 10 to 20 yr with different stages of CKD and to identify risk factors for early arteriopathy. High-resolution ultrasonography was conducted of common cIMT and femoral superficial artery IMT. Fifty-five children with stages 2 to 4 CKD (GFR 51 ± 31 ml/min per 1.73 m2), 37 on dialysis, and 34 after renal transplantation (Rtx; GFR 73 ± 31 ml/min per 1.73 m2) were studied. Control subjects were 270 healthy children, matched for age and gender. Compared with control subjects, cIMT, femoral superficial artery IMT (both as absolute values and as SD score of median of normal value), wall cross-sectional area, and lumen cross-sectional area of carotid artery were significantly increased in all patient groups and most markedly abnormal in dialysis patients. cIMT in CKD and Rtx patients was significantly lower in comparison with dialysis patients. cIMT correlated with mean past serum Ca × P product, the cumulative dose of calcium-based phosphate binders, and the time-averaged mean calcitriol dose. The cumulative phosphate binder intake, time-averaged Ca × P product, and young age were independent predictors of an increased cIMT. In children with CKD, thickening of IMT occurs early in the course of disease and is most marked in dialyzed patients. The changes may be partly reversible after Rtx.
Minimizing steroid exposure in pediatric renal transplant recipients can improve linear growth and reduce metabolic disorders. This randomized multicenter study investigated the impact of early steroid withdrawal on mean change in height standard deviation score (SDS) and the safety and efficacy of two immunosuppressive regimens during the first 6 months after transplantation. Children received tacrolimus, MMF, two doses of daclizumab and steroids until day 4 (TAC/MMF/DAC, n=98) or tacrolimus, MMF and standard‐dose steroids (TAC/MMF/STR, n=98). Mean change in height SDS was 0.16 ± 0.32 with TAC/MMF/DAC and 0.03 ± 0.32 with TAC/MMF/STR. The mean treatment group difference was 0.13 (p < 0.005 [95% CI 0.04–0.22]), 0.21 in prepubertal (p = 0.009 [95% CI 0.05–0.36]) and 0.05 in pubertal children (p = ns). Frequency of biopsy‐proven acute rejection was 10.2%, TAC/MMF/DAC, and 7.1%, TAC/MMF/STR. Patient and graft survival and renal function were similar. Significantly greater reductions in total cholesterol and triglycerides but significantly higher incidences of infection and anemia were found with TAC/MMF/DAC (p < 0.05 all comparisons). Early steroid withdrawal significantly aided growth at 6 months more so in prepubertal than pubertal children. This was accompanied by significantly better lipid and glucose metabolism profiles without increases in graft rejection or loss.