Evidences have suggested complement C3 is a biomarker for nonalcoholic fatty liver disease (NAFLD) in the general population.
The present study was conducted to explore the predictive function of C3 for NAFLD in chronic kidney disease (CKD) patients.
CKD patients were recruited for evaluation of their liver function, kidney function, serum lipids, glycated hemoglobin, blood, and immune function. The glomerular filtration rate was calculated using the CKD-EPI equation. NAFLD was diagnosed according to predefined ultrasonographic criteria.
A total of 648 consecutive CKD patients were included, with 216 (33.3%) patients diagnosed with NAFLD. The NAFLD group had significant higher levels of serum protein, serum albumin, triglycerides, glycated hemoglobin, complement C3, hemoglobin (p = 0.001), alanine aminotransferase (p = 0.002), estimated glomerular filtration rate (p = 0.007), and C4 (p = 0.043) and lower levels of cystatin C, β2-microglobulin, proteinuria (p = 0.001), and high-density lipoprotein cholesterol (p = 0.008). In a logistic regression model, only complement C3 (OR = 1.003; 95% CI 1.002-1.004, p = 0.001) was associated with a higher likelihood of being diagnosed with NAFLD. Finally, we constructed ROC curves for complement C3 for prediction of having NAFLD. The best cut-off for complement C3 was 993.5 mg/L and it yielded a sensitivity of 63.9% and a specificity of 70.1%.
Our study revealed that complement C3 can be used as a surrogate biomarker of NAFLD in CKD patients.

© 2020 The Author(s) Published by S. Karger AG, Basel.

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