Lawrence Michael R, Arnetz Judith E, Counts Scott E, Ahmed Aiesha, Arnetz Bengt B
Division of Clinical Neuropsychology, Corewell Health, Grand Rapids, Michigan, United States of America.
Department of Neurology, Corewell Health, Grand Rapids, Michigan, United States of America.
PLoS One. 2025 May 15;20(5):e0315486. doi: 10.1371/journal.pone.0315486. eCollection 2025.
Substantial numbers of individuals who contract COVID-19 experience long-lasting cognitive symptoms such as brain fog. Yet research to date has not compared these patients with healthy controls with a history of laboratory-confirmed COVID-19 infection, making it difficult to understand why certain COVID patients develop post-COVID cognitive symptoms while others do not. The objective of this pilot study was to compare two groups of laboratory-confirmed post-COVID patients, with and without cognitive symptoms, on measures of cognitive and psychological functioning, self-reported perceptions of functional status and quality of life, and biomarkers of stress, inflammation, and neuroplasticity. Using a case-control design, 17 participants were recruited from a healthcare system in western Michigan, USA in 2022-2024. All participants were aged 25-65 and had a positive polymerase chain reaction (PCR) test confirming previous COVID-19 infection. Ten participants reported cognitive symptoms (long COVID group) while seven were fully recovered with no residual symptoms (controls). All participants underwent an interview on their self-rated health and quality of life, a battery of neurocognitive tests, and blood draw for biomarker analysis. No group differences were detected for neuropsychological test measures except for letter fluency where the long COVID group scored significantly lower (p < .05). The long COVID group had significantly lower ratings than controls on quality of life, physical health, emotional functioning, and psychological well-being. Serum levels of nerve growth factor (NGF), a biomarker of brain plasticity, were significantly lower in the long COVID group, which was significantly more likely than controls to have serum levels of inflammatory marker (interleukin (IL)-10) values greater than or equal to the median (p = 0.015). Biomarker analyses suggest possible prolonged inflammatory processes in long COVID patients compared to fully recovered patients. Results of decreased neuroplastic functioning give credence to patients' reports of post-COVID changes in brain function.
大量感染新冠病毒的人会出现持续时间较长的认知症状，如脑雾。然而，迄今为止的研究尚未将这些患者与有实验室确诊新冠病毒感染史的健康对照者进行比较，因此很难理解为什么某些新冠患者会出现新冠后认知症状，而另一些患者则不会。这项初步研究的目的是比较两组实验室确诊的新冠后患者，一组有认知症状，另一组没有认知症状，比较他们在认知和心理功能、自我报告的功能状态和生活质量感知以及压力、炎症和神经可塑性生物标志物方面的情况。采用病例对照设计，2022年至2024年期间从美国密歇根州西部的一个医疗系统招募了17名参与者。所有参与者年龄在25岁至65岁之间，聚合酶链反应（PCR）检测呈阳性，证实此前感染过新冠病毒。10名参与者报告有认知症状（长新冠组），而7名已完全康复且无残留症状（对照组）。所有参与者都接受了关于自评健康和生活质量的访谈、一系列神经认知测试，并进行了血液抽取以进行生物标志物分析。除了字母流畅性测试外，神经心理学测试指标在两组之间未检测到差异，长新冠组在字母流畅性测试中的得分显著较低（p < 0.05）。长新冠组在生活质量、身体健康、情绪功能和心理健康方面的评分显著低于对照组。作为大脑可塑性生物标志物的神经生长因子（NGF）血清水平在长新冠组中显著较低，该组血清炎症标志物（白细胞介素（IL）-10）水平大于或等于中位数的可能性显著高于对照组（p = 0.015）。生物标志物分析表明，与完全康复的患者相比，长新冠患者可能存在炎症过程延长的情况。神经可塑性功能下降的结果证实了患者关于新冠后大脑功能变化的报告。
