Usefulness of Retinol-Binding Protein in Predicting Mortality in Patients With Chronic Liver Disease.

Background and Aim: Rapid turnover proteins (RTPs), including retinol-binding protein (RBP), prealbumin, and transferrin, are useful in evaluating dynamic nutritional status. This study aimed to investigate the relationship between serum RTP levels and mortality in patients with chronic liver disease (CLD). Methods: We evaluated 341 patients with CLD admitted between October 2011 and December 2021. Those with RBP levels below 2.7 mg/dL for males and 1.9 mg/dL for females were included in the low RBP group. Factors associated with mortality and low RBP were evaluated using the Cox proportional hazard regression and logistic regression models. Results: The median age of the included patients was 67 years, and 48% were male. The median model for end-stage liver disease (MELD) score was 8 points, and the median RBP, prealbumin, and transferrin levels were 1.5 mg/dL, 11 mg/dL, and 227 mg/dL, respectively. During a median observational period, 23% of the patients died. Multivariate analysis showed that the RBP level (hazard ratio, 0.62; 95% confidence interval [CI], 0.46-0.81) was independently associated with mortality, while prealbumin and transferrin were not. Additional analysis revealed that male sex (odds ratio, 8.62; 95% CI, 2.56-29.00) and albumin level (odds ratio, 0.10; 95% CI, 0.04-0.26) were significantly associated with the low RBP levels in patients with CLD. Conclusions: The serum RBP level is a dynamic biomarker associated with mortality in patients with CLD, independent of liver functional reserve, and it may be a useful indicator for nutritional intervention in these patients.