Data Sheet 1_Cognitive assessment in myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS): a cognitive substudy of the multi-site clinical assessment of ME/CFS (MCAM).docx

IntroductionPatients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) experience cognitive problems with attention, information processing speed, working memory, learning efficiency, and executive function. Commonly, patients report worsening of cognitive symptoms over time after physical and/or cognitive challenges. To determine, monitor, and manage longitudinal decrements in cognitive function after such exposures, it is important to be able to screen for cognitive dysfunction and changes over time in clinic and also remotely at home. The primary objectives of this paper were: (1) to determine whether a brief computerized cognitive screening battery will detect differences in cognitive function between ME/CFS and Healthy Controls (HC), (2) to monitor the impact of a full-day study visit on cognitive function over time, and (3) to evaluate the impact of exercise testing on cognitive dysfunction.
MethodsThis cognitive sub-study was conducted between 2013 and 2019 across seven U.S. ME/CFS clinics as part of the Multi-Site Clinical Assessment of ME/CFS (MCAM) study. The analysis included 426 participants (261 ME/CFS and 165 HC), who completed cognitive assessments including a computerized CogState Brief Screening Battery (CBSB) administered across five timepoints (T0-T4) at the start of and following a full day in-clinic visit that included exercise testing for a subset of participants (182 ME/CFS and 160 HC). Exercise testing consisted of ramped cycle ergometry to volitional exhaustion. The primary outcomes are performance accuracy and latency (performance speed) on the computerized CBSB administered online in clinic (T0 and T1) and at home (T2-T4).
ResultsNo difference was found in performance accuracy between ME/CFS and HCs whereas information processing speed was significantly slower for ME/CFS at most timepoints with Cohen’s d effect sizes ranging from 0.3–0.5 (p < 0.01). The cognitive decline over time on all CBSB tasks was similar for patients with ME/CFS independent of whether exercise testing was included in the clinic visit.
ConclusionThe challenges of a clinic visit (including cognitive testing) can lead to further cognitive deficits. A single short session of intense exercise does not further reduce speed of performance on any CBSB tasks.

引言
肌痛性脑脊髓炎/慢性疲劳综合征（Myalgic Encephalomyelitis/Chronic Fatigue Syndrome, ME/CFS）患者会出现注意力、信息处理速度、工作记忆、学习效率及执行功能方面的认知障碍。通常，患者会报告在躯体或认知负荷后，其认知症状会随时间进展而加重。为了确定、监测并管理此类负荷后认知功能的纵向减退，能够在临床环境以及居家远程场景下筛查认知功能障碍及其随时间的变化，具有重要意义。本研究的主要目标包括：(1) 验证简短的计算机化认知筛查组合能否区分ME/CFS患者与健康对照（Healthy Controls, HC）的认知功能差异；(2) 监测为期一日的临床访视对认知功能的随时间变化影响；(3) 评估运动测试对认知功能障碍的影响。
方法
本认知亚研究作为ME/CFS多中心临床评估（Multi-Site Clinical Assessment of ME/CFS, MCAM）研究的一部分，于2013年至2019年间在美国7家ME/CFS诊疗机构开展。本分析纳入426名受试者（261名ME/CFS患者与165名健康对照），所有受试者均完成了认知评估，其中包括计算机化的CogState简短筛查组合（CogState Brief Screening Battery, CBSB）；评估共设置5个时间节点（T0至T4），分别于为期一日的临床访视开始前及结束后完成，其中部分受试者（182名ME/CFS患者与160名健康对照）需在访视中完成运动测试。运动测试采用递增功率自行车运动至力竭的方案。本研究的主要结局指标为：在临床环境（T0与T1）及居家场景（T2至T4）中通过线上施测的CBSB任务的正确率与反应时（即完成速度）。
结果
ME/CFS患者与健康对照的任务正确率无显著差异，但在多数时间节点上，ME/CFS患者的信息处理速度显著更慢，Cohen's d效应量区间为0.3~0.5（p < 0.01）。无论临床访视是否包含运动测试，ME/CFS患者在所有CBSB任务中的认知功能随时间的下降趋势均一致。
结论
临床访视带来的负荷（包括认知测试本身）可能会进一步加重认知缺损。单次短时高强度运动不会进一步降低任何CBSB任务的完成速度。