Fat‐Soluble Vitamins in Advanced CKD/ESKD: A Review

Abstract

Patients requiring dialysis often experience a significant decline in their nutritional status through a combination of chronic disease, reduced appetite, and dietary restrictions, which places them at risk for vitamin deficiencies. The concept of vitamin deficiency has evolved from obvious deficiency states to the subtle effects that suboptimal intake may have on chronic disease prevalence or progression. The purpose of this study was to summarize the current state of knowledge regarding the status of the fat-soluble vitamins (A, D, E, and K) in patients with chronic kidney disease receiving hemodialysis.

Vitamins (A, C and E) and oxidative status of hemodialysis patients treated with HFR and HFR-Supra

“…A/RBP molar ratios; AOPP values were in the normal range, while TAS values were higher-than-normal. For all parameters but AOPP, the levels we found were in agreement with those previously reported for uremic subjects [3, 8, 11, 40–42]. At difference, AOPP levels were significantly lower than it was previously reported for these patients [36].…”

“…Oxidative stress in ESRD is due to both enhanced oxidative capacity and reduced antioxidant defenses, the latter including impaired enzyme activities and decreased levels of antioxidant vitamins [1–3]. Vitamin deficiencies in ESRD may originate from diet restriction, reduced absorption by medications and co-morbidities, uremia-related alterations of metabolic pathways and intradialytic losses [3]. Vitamin C (Vit C) is the most abundant and effective water-soluble antioxidant in human plasma.…”

“…Vitamin E (Vit E) and Vitamin A (Vit A) are two fat-soluble plasma antioxidants and are transported in plasma by lipoproteins and retinol binding protein (RBP), respectively. Although inconsistent levels of Vit E levels have been reported in uremic patients [3], the administration of this vitamin has been suggested as a promising therapeutic strategy to limit both oxidative stress and its clinical consequences in hemodialysis patients; however, results obtained to date are contradictory [3, 9, 10]. Vit.…”

“…Vit. A levels are generally increased in ESRD patients, mainly due to homeostatic dysregulation of its plasma carrier, the retinol binding protein (RBP) [3, 11]. Nonetheless, in ESRD patients relatively higher Vit.…”

Calcitriol Accelerates Vascular Calcification Irrespective of Vitamin K Status in a Rat Model of Chronic Kidney Disease with Hyperphosphatemia and Secondary Hyperparathyroidism

“…MGP is a vitamin K-dependent protein and a potent inhibitor of VC (Luo et al, 1997). The g-carboxylation of five Gla domains by the enzyme g-glutamyl carboxylase, which requires vitamin K as a cofactor, is critical to the calcium binding function of MGP (Krueger et al, 2009;Holden et al, 2012). Marked MGP upregulation has been demonstrated in vivo in the aortas of animals with experimental CKD (Sweatt et al, 2003;Lomashvili et al, 2011), although the increase is of the inactive form of MGP when there is insufficient vitamin K-mediated carboxylation.…”