Liver fat content is independently associated with microalbuminuria in a normotensive, euglycaemic Chinese population: a community-based, cross-sectional study

Objective: Non-alcoholic fatty liver disease (NAFLD) is associated with microalbuminuria (MA) in patients with diabetes/pre-diabetes. Whether this association is mediated by blood glucose and blood pressure (BP) remains unclear. This study investigated whether liver fat content (LFC) was associated with MA in a normotensive and non-diabetic population.

Design: A cross-sectional substudy.

Settings: LFC was determined from the hepatic/renal echogenicity ratio at ultrasound. MA was defined as an albumin-to-creatinine ratio (ACR) of 30-300 µg/mg (early- morning urine sample). Multivariable logistic regression and receiver operating characteristic (ROC) curve analyses were used to evaluate LFC as a predictor of MA.

Participants: Between May 2010 and June 2011, this cross-sectional, community-based study enrolled residents from Shanghai (China), aged ≥40 years and with normal glucose tolerance and BP.

Results: A total of 550 residents (median age, 57 years; 174 men) were enrolled and stratified according to LFC quartiles. ACR (p<0.001) and MA prevalence (p=0.012) increased across the LFC quartiles. Multivariable logistic regression showed that the OR for MA (per SD increase in LFC) was 1.840 (95% CI 1.173 to 2.887, p=0.008) after adjustment for potential confounders including age, gender, waist-hip ratio, blood urea nitrogen, systolic and diastolic BP, fasting blood glucose, postprandial glucose, low-density lipoprotein-cholesterol, triglycerides, high-density lipoprotein-cholesterol, total cholesterol, estimated glomerular filtration rate and lipid-lowering drugs. The ROC analysis revealed that the optimal LFC cut-off value for predicting MA was 6.82%.

Conclusion: LFC is independently associated with MA in normotensive, euglycaemic middle-aged and elderly Chinese individuals. Screening for MA in people with NAFLD might facilitate early intervention to minimise kidney disease risk.