阿尔茨海默病 (AD) 的特点是异常炎症反应，而补体 C5a (C5a) 已知会引发炎症。本研究旨在探讨 AD 患者血清 C5a、炎症反应和认知功能之间的关联。总共包括 242 名 CE 患者和 132 名年龄匹配的对照者。酶联免疫吸附测定显示，随着 AD 阶段的进展，C5a、白细胞介素 (IL)-4、IL-6、IL-10、IL-1β 和肿瘤坏死因子 (TNF)-α 的水平升高。 Pearson 相关系数和受试者工作特征曲线显示，血清 C5a 水平、炎症细胞因子水平、神经精神量表 (NPI) 和日常生活活动 (ADL) 评分之间呈正相关，与简易精神状态检查 (MMSE) 和蒙特利尔认知能力呈负相关评估（MoCA）分数。血清C5a高于68.68pg/mL有助于AD的诊断。多变量logistic分析显示，血清C5a是IL-1β/IL-6/IL-10/TNF-α的独立危险因素，也是IL-4的独立保护因素。较高的血清 C5a 水平与较低的 MMSE 和 MoCA 评分相关。总之，血清 C5a 水平升高有利于 AD 诊断以及炎症和认知功能障碍的预测。版权所有 © 2024。由 Elsevier B.V. 出版。

Alzheimer's disease (AD) is characterized by abnormal inflammatory responses, and complement C5a (C5a) is known to initiate inflammation. This study aimed to investigate the associations between serum C5a, inflammatory responses, and cognitive function in AD patients. A total of 242 CE patients and 132 age-matched controls were included. Enzyme-linked immunosorbent assay revealed increased levels of C5a, interleukin (IL)-4, IL-6, IL-10, IL-1β, and tumor necrosis factor (TNF)-α with advancing stages of AD. Pearson correlation coefficient and receiver operating characteristic curve revealed positive correlations between serum C5a levels, inflammatory cytokine levels, Neuropsychiatric Inventory (NPI) and Activities of Daily Living (ADL) scores, and negative correlations with Mini-mental State Examination (MMSE) and Montreal cognitive assessment (MoCA) scores. Serum C5a above 68.68 pg/mL could aid in the diagnosis of AD. Multivariable logistic analysis revealed that serum C5a was an independent risk factor for IL-1β/IL-6/IL-10/TNF-α and an independent protective factor for IL-4. Higher serum C5a levels were associated with lower MMSE and MoCA scores. In conclusion, elevated serum C5a levels were beneficial for AD diagnosis and predictive of inflammation and cognitive dysfunction.Copyright © 2024. Published by Elsevier B.V.