Department of Psychology, University of Campania "Luigi Vanvitelli", Caserta, Italy.
Department of Psychology, University of Campania "Luigi Vanvitelli", Caserta, Italy.
Mult Scler Relat Disord. 2019 May;30:265-276. doi: 10.1016/j.msard.2019.02.017. Epub 2019 Feb 14.
Inconsistent evidence is available about the possibility that cognitive reserve (CR) moderates the impact of disease progression, evaluated by MRI biomarkers (lesion load, white matter or gray matter volumes) or clinical proxies of physical disability (i.e. the Expanded Disability Status Scale, EDSS) on cognition in Multiple Sclerosis (MS). A meta-analytic study with a meta-regression approach was performed to investigate the possible role of CR as moderator of the impact of brain damage and physical disability on cognition.
Two literature searches were performed to retrieve all studies that investigated the relationship between MRI biomarkers and cognition, or the relationship between physical disability and cognition. Data about CR proxies (education, vocabulary knowledge, CR questionnaires) were also collected. We performed several meta-analyses with random effect models (Hedges' g), and a moderator analysis with a meta-regression approach (with CR entered as a numerical moderator). A p value of < 0.05 was set for statistical significance.
We found a significant impact of lesion load and gray matter abnormalities on most cognitive domains. Meta-regression showed that CR significantly moderated the relationship between brain damage and verbal fluency. Moreover, we found a significant impact of physical disability on cognitive functioning, but CR did not mitigate the relationship between EDSS and cognitive performance.
The present findings limit the protective role of CR against the impact of the brain damage to selected aspects of cognition (those related to lexical access and cognitive flexibility) in MS. These findings reinforce the need for longitudinal studies exploring the moderator effect of CR over the course of MS.
关于认知储备（CR）是否能缓和磁共振成像生物标志物（病灶负荷、白质或灰质体积）或身体残疾的临床替代指标（即扩展残疾状态量表，EDSS）评估的疾病进展对多发性硬化症（MS）认知的影响，目前的证据并不一致。本研究采用元分析和元回归方法，旨在探讨 CR 作为脑损伤和身体残疾对认知影响的调节因素的可能作用。
进行了两次文献检索，以检索所有研究病灶负荷与认知之间、身体残疾与认知之间的关系。还收集了关于 CR 替代指标（教育、词汇知识、CR 问卷）的数据。我们采用随机效应模型（Hedges'g）进行了几项荟萃分析，并采用元回归方法进行了调节分析（将 CR 作为数值调节因素）。设定统计学显著性水平为 p 值 < 0.05。
我们发现病灶负荷和灰质异常对大多数认知域有显著影响。元回归显示，CR 显著调节了脑损伤与言语流畅性之间的关系。此外，我们发现身体残疾对认知功能有显著影响，但 CR 并不能减轻 EDSS 与认知表现之间的关系。
本研究结果限制了 CR 对 MS 患者脑损伤影响的保护作用，仅针对认知的某些方面（与词汇获取和认知灵活性相关的方面）。这些发现强调了需要进行探索 CR 在 MS 病程中作为调节因素的作用的纵向研究。
