Serum complement C3 as a diagnostic biomarker for metabolic dysfunction -associated steatotic liver disease in middle-aged and elderly adults: a cross-sectional study

作者：Dan Ye, Hai‐fen Ma, Jingjing Zhou, Jiaofeng Wang, Jiaheng Shi, Jie Chen, Zhijun Bao, Xiaona Hu · 发表于：BMC Gastroenterology · 年份：2025 · DOI：10.1186/s12876-025-04394-w · 被引用次数：2 · 研究领域：Complement system in diseases、Liver Disease and Transplantation、Liver Disease Diagnosis and Treatment

BACKGROUND: Metabolic dysfunction-associated steatotic liver disease (MASLD) is the leading cause of chronic liver disease globally, with significant liver fibrosis (SLF) determining clinical outcomes. Although complement activation is involved in MASLD pathogenesis, the clinical significance of circulating complement proteins (C1q, C3, C4, total activity) in aging populations remains unclear. This cross-sectional study aimed to evaluate the association between serum complement levels and MASLD/SLF in middle-aged and elderly adults. METHODS: We recruited 266 consecutive MASLD patients (age ≥ 45) and 150 age- and sex-matched healthy controls from Huadong Hospital. Multivariate logistic regression identified independent predictors of MASLD and SLF. Nonlinear relationships were assessed using restricted cubic splines. Spearman's correlation and mediation analyses explored clinical associations, while ROC curves evaluated diagnostic performance against established non-invasive indices. RESULTS: MASLD patients showed significantly higher levels of C1q, C3, C4, and total complement activity than controls (P < 0.05). After multivariate adjustment, C3 was independently associated with MASLD (OR = 1.04 per mg/dL, 95% CI: 1.02-1.06; P < 0.001). A nonlinear, inverted U-shaped relationship was observed between C3 and MASLD risk (P = 0.015), with peak risk at 143 mg/dL (OR = 2.53). C3 demonstrated high diagnostic accuracy for MASLD (AUC = 0.80, 95% CI: 0.75-0.85), comparable to validated ...