RESUMO
OBJECTIVES: Non-alcoholic fatty liver disease (NAFLD) is related to obesity, insulin resistance, dyslipidemia, and metabolic syndrome. The increasing prevalence of NAFLD results in a significant number of patients manifesting chronic liver disease over time. The aim of this study was to analyze the predictive factors to estimate NAFLD severity in patients who are candidates for Roux-en-Y gastric bypass. METHODS: This descriptive observational study was conducted with 136 obese patients who were candidates for Roux-en-Y gastric bypass and had mild, moderate, or severe NAFLD. RESULTS: Severe NAFLD was more prevalent among the men (P = 0.007), and mild NAFLD was more prevalent among the women (P = 0.007). Hyperferritinemia was observed in the group with severe NAFLD (P = 0.01). Neck circumference and waist-to-height ratio were associated with an increased risk when comparing the groups with mild and severe NAFLD and those with moderate and severe NAFLD (P = 0.023 and P = 0.001, respectively); the alanine aminotransferase (ALT) and aspartate aminotransferase ratio values were >1 (P = 0.002) in the same comparisons. The regression analyses showed that an increase of 1 ng/mL in vitamin D reduced the chances of severe steatosis by 10% (P = 0.043), and an increase of 1 U/L ALT increased the chances of severe steatosis by 13% (P = 0.002). CONCLUSION: High neck circumference and low waist-to-height ratio values, male sex, hyperferritinemia, increased serum ALT values, and decreased vitamin D levels were related to the risk for severe NAFLD.