Blood biomarkers of traumatic brain injury and cognitive impairment in older veterans

Objective: To determine whether blood-based biomarkers can differentiate older veterans with and without traumatic brain injury (TBI) and cognitive impairment (CI). Methods: We enrolled 155 veterans from two veterans’ retirement homes: 90 without TBI and 65 with TBI history. Participants were further separated into CI groups: Controls (no TBI, no CI), n=60; no TBI with CI, n=30; TBI without CI, n=30; and TBI with CI, n=35. TBI was determined by the Ohio State University TBI Identification Method. CI was defined as impaired cognitive testing, dementia diagnosis, or use of dementia medication. Blood specimens were enriched for CNS-derived exosomes. Proteins [neurofilament light (NfL), total tau, glial fibrillary acidic protein (GFAP), alpha synuclein, β-amyloid 42 (Aβ42), and phosphorylated tau (pTAU)] and cytokines [tumor necrosis factor alpha (TNFa), interleukin 6 (IL-6) and interleukin 10] were measured using ultrasensitive immunoassays. Results: Veterans were, on average, 79 yea...研究目的：探究基于血液的生物标志物能否区分伴与不伴创伤性脑损伤（Traumatic Brain Injury, TBI）及认知障碍（Cognitive Impairment, CI）的老年退伍军人。 研究方法：本研究从两家退伍军人养老院招募155名退伍军人，其中90名无创伤性脑损伤病史，65名有创伤性脑损伤病史。进一步将受试者按认知状态分组：对照组（无创伤性脑损伤、无认知障碍），n=60；无创伤性脑损伤伴认知障碍组，n=30；有创伤性脑损伤无认知障碍组，n=30；有创伤性脑损伤伴认知障碍组，n=35。创伤性脑损伤采用俄亥俄州立大学创伤性脑损伤识别方法（Ohio State University TBI Identification Method）进行判定；认知障碍定义为认知测试结果异常、痴呆诊断或使用痴呆治疗药物。采集血液标本并富集中枢神经系统源性外泌体（CNS-derived exosomes），采用超灵敏免疫分析法检测相关蛋白与细胞因子：蛋白包括神经丝轻链（Neurofilament Light, NfL）、总tau蛋白、胶质纤维酸性蛋白（Glial Fibrillary Acidic Protein, GFAP）、α-突触核蛋白、β-淀粉样蛋白42（β-amyloid 42, Aβ42）以及磷酸化tau（phosphorylated tau, pTAU）；细胞因子包括肿瘤坏死因子α（Tumor Necrosis Factor alpha, TNF-α）、白细胞介素6（Interleukin 6, IL-6）与白细胞介素10。 研究结果：退伍军人平均年龄为79岁……