Vitamin A and retinol-binding protein deficiency among chronic liver disease patients

Abstract

Vitamin A deficiency (VAD) is associated with the progression of chronic liver disease (CLD). The aim in this study was to assess levels of serum retinol and retinol-binding protein (RBP) as well as liver vitamin A stores in the presence of liver cirrhosis and hepatocellular carcinoma. Methods: We ascertained the serum retinol and RBP levels of randomly selected CLD patients divided into two groups, one given 1500 UI (n ¼ 89) and the other receiving 2500 UI (n ¼ 89) doses of retinyl palmitate for the relative dose response test. Blood samples were collected in a fasting state and 5 and 7 h after supplementation. Results: The prevalence of VAD was 62.4%. There was a progressive drop in serum retinol (P < 0.001) and RBP (P ¼ 0.002) according to the severity of the liver disease, and a greater prevalence of severe VAD was noted in cirrhosis Child & Pugh C (52.8%). Fifty percent of the pa tients presented a low availability of RBP relative to retinol concentration, and there was no peak in RBP levels regardless of the dose of retinyl palmitate administered. Conclusions: Our findings suggest serum retinol and RBP are relevant as indicators of vitamin A nutritional status in the presence of CLD. Liver vitamin A store cannot be evaluated using the RDR test because CLD causes a reduction in RBP synthesis and interferes with the mobilization of endogenous vitamin A. Considering how the patients already showed a drop in RBP relative to retinol concentrations, it is reasonable to assume vitamin A supplementation may trigger harmful effects in CLD patients.