RESUMO
BACKGROUND: Oxidative stress plays a role in nonalcoholic fatty liver disease (NAFLD) pathogenesis and may increase consumption of vitamin A for antioxidant purposes. It is hypothesized that drops in vitamin A concentration induce liver disease progression and increase hepatocellular carcinoma risk. The aim of this study was to assess concentrations of serum and liver retinol in the class III obese and correlate them with the histological diagnosis of NAFLD. METHODS: The sample group was composed of 68 class III obese (body mass index, BMI ≥ 40 kg/m(2)) males and females who underwent bariatric surgery for treating obesity. Concentrations of serum and liver retinol were determined using high-performance liquid chromatography. The cutoff values used to denote inadequate serum and liver retinol stores were <1.05 µmol/L and ≤20 µg/g, respectively. Anthropometric measurements were taken, and NAFLD was diagnosed via histological assessment. RESULTS: All the patients had some degree of NAFLD. Inadequate concentrations of serum and liver retinol were found in 35.9 and 67.9% of them, respectively. A significant association was found between liver retinol concentrations and the histological classification of the disease (p < 0.001). No such association was found for serum retinol. CONCLUSIONS: This study confirms the association between liver retinol and degree of NAFLD, underscoring the need for further research in this area, to identify which patients might benefit from supplementation of vitamin A.