Risk factors and biomarkers of nonalcoholic fatty liver disease: an observational cross-sectional population survey

Objective Non-alcoholic fatty liver disease (NAFLD) is a major public health burden in China, and its prevalence is increasing. This study aimed to determine the risk factors and biomarkers of NAFLD. Design An observational cross-sectional primary survey. Setting Central China. Participants The study included 1479 participants aged over 18 and below 80 years, not currently being treated for cancer or infectious disease or no surgery in the previous year, and no history of cancer or an infectious disease. Participants underwent clinical examination, metabolomic assay and anthropometric assessment. Univariate and logistic regression analyses were used to evaluate associations between covariates and NAFLD. Main outcome measures Risk factors and metabolic biomarkers including sex, body mass index, hypertension, body fat ratio, blood triglycerides, blood fasting glucose, liver enzyme elevation, uric acid and oleic acid-hydroxy oleic acid (OAHOA). Results Data from the 447 participants (mean age 44.3 +/- 11.9 years) were analysed, and the prevalence of NAFLD was 24.7%. Male sex (OR 3.484, 95% CI 2.028 to 5.988), body mass index >= 24 kg/m(2) (OR 8.494, 95% CI 5.581 to 12.928), body fat ratio (>= 25 for women, >= 20 for men) (OR 1.833, 95% CI 1.286 to 2.756), triglycerides >= 1.7 mmol/L (OR 1.340, 95% CI 1.006 to 1.785), fasting glucose >= 6.1 mmol/L (OR 3.324, 95% CI 1.888 to 5.850), blood pressure >= 140/90 mm Hg or antihypertensive drug treatment (OR 1.451, 95% CI 1.069 to 1.970), uric acid (>= 357 mu mol/L for women, >= 416 mu mol/L for men) (OR 2.755, 95% CI 2.009 to 3.778) and OAHOA (< 5 nmol/L) (OR 1.340, 95% CI 1.006 to 1.785) were independent predictors of NAFLD (all P<0.05). These results were verified by all 1479 participants. Conclusions NAFLD was common among the study participants. In particular, NAFLD was correlated with uric acid. We identified OAHOA as a novel marker of NAFLD prevalence. It provides a reference on the prevention of NAFLD and related metabolic diseases with the rapid urbanisation, technological advancement and population ageing in China over the recent decades.