Determinants of baroreflex function in juvenile end-stage renal disease

Abstract

Arterial baroreflex sensitivity (BRS) is markedly reduced in middle-aged patients with end-stage renal disease (ESRD), due to the combined effects of aging, arterial stiffening, and autonomic neuropathy. Much less is known about the effects of ESRD on arterial baroreflex in juvenile patients. Therefore, we investigated baroreflex function and its relation to carotid artery elasticity and heart rate variability in children and young adults with ESRD. We studied 42 subjects (9-30 years): 14 patients on maintenance hemodialysis (HD), 14 renal transplant recipients (RT), and 14 healthy control subjects (C). Baroreflex function was determined by pharmacological (BRS) and spontaneous (sequence and spectral indices) techniques. Carotid artery elasticity was characterized by stiffness index beta. Heart rate variability was assessed using time and frequency domain measures. Data are expressed as mean+/-s.d. BRS was markedly reduced in HD as compared to C (10.0+/-4.2 vs 25.7+/-5.9 ms/mm Hg); spontaneous indices were reduced to similar extent. Carotid artery stiffness was approximately 50% higher in HD than in C and was inversely related to BRS. Heart rate variability was also compromised in HD, and was directly related to spontaneous indices. No significant differences existed in any of these variables between RT and C. Decreased baroreflex function in juvenile HD is partly due to loss of carotid artery elasticity and partly due to impaired heart rate variability. Renal transplantation may partly prevent impairment or improve compromised baroreflex function in young patients with ESRD.

Cardiovascular Autonomic Dysfunction in Chronic Kidney Disease: a Comprehensive Review

“…The inability to transduce BP changes to the brain, as recently shown in our CKD model in which impaired baroreceptor afferent function correlated with vascular remodeling in the aortic arch [13••], then is associated with defective baroreflex control of autonomic outflows and altered tonic levels of sympathetic and vagal efferent activity. Indeed, studies have shown a negative association between BRS and the magnitude of vascular calcification [97,101] and arterial stiffness [70] in chronic hemodialysis patients. In renal transplant patients, increased levels of muscle SNA were correlated with impaired arterial distensibility [102].…”

“…In clinical practice, prognostic information on cardiovascular morbidity and mortality in CKD may be derived by (1) measuring cardiac BRS, an independent predictor of sudden cardiac death accompanying CKD [24], and (2) using the baroreflex effectiveness index (BEI), a measure of the number of times baroreflex is active in controlling HR in response to BP fluctuations [67]; both tools are recognized as strong independent predictors of long-term survival in the CKD population [24]. Indeed, HR BRS, either spontaneous [24,[68][69][70] or evoked by pharmacologic manipulation of BP [31,65,70], and BEI [24] are reduced in CKD, and, most importantly, deficits correlate with reductions in the GFR [69], suggesting a direct association between deterioration in renal function and alterations in the cardiac baroreflex mechanism, rendering these markers useful in assessing cardiovascular risk in CKD.…”

Echocardiographic, electrocardiographic and blood pressure changes induced by icodextrin solution in diabetic patients on peritoneal dialysis

“…In dialysis patients, significant reduction in activity in both systems has been reported. 35,36 In diabetic patients without renal failure, pronounced derangement has been noted as strongly related to metabolic control. 37-39 R-R variability as an index of autonomic neuropathy was found associated with LVM in diabetic patients on hemodialysis, 40 41 It was hypothesized that an accumulation of icodextrin metabolites in the bloodstream exerts an osmotic effect, which increases the blood volume and, secondarily, BP and NT-pro-BNT.…”

High Pulse-Wave Velocity Defines a Very High Cardiovascular Risk Cohort of Dialysis Patients under Age 60

“…While these changes appear in the early stages of CKD, they are more pronounced in advanced stages. In CKD, poorly controlled (especially systolic) hypertension is associated with advanced arteriosclerosis, rigid arteries, impaired baroreflex sensitivity and autonomic dysfunction, creating a vicious cycle [41,42] . Additionally, in ESRD, the synergism between hyperphosphatemia, calcitriol, calcium carbonate, warfarin, hypertension and atherosclerosis provides the perfect breeding ground for vascular calcification [15,38] .…”