Statistical analysis
All statistical analyses were conducted using SPSS 22.0 (IBM Corp., Armonk, NY, USA). Continuous variables are presented as mean±standard deviation for those with normal distributions and as median and interquartile range for those with skewed distributions. Categorical variables are presented as numbers with percentages. Continuous variables were compared using the Student’st -test or Mann–Whitney U test, and categorical variables were compared using the chi-squared or Fisher’s exact tests, as applicable. Correlations between D-lactate and clinical parameters in patients with NAFLD were determined using Pearson’s or Spearman’s correlation, as applicable. P˂0.05 (two-sided) was considered to indicate statistical significance.