Department of Neurology, Medical School, University of Cyprus, Old Road Nicosia-Limmasol 215-6, CY2029 Aglantzia, Nicosia, Cyprus; Department of Neurology, NIMTS Hospital, Monis Petraki 10-12, GR11521, Athens, Greece.
The Multiple Sclerosis Center, 2nd Department of Neurology, AHEPA University Hospital, Medical School, Aristotle University of Thessaloniki, Stilp. Kyriakidi 1, GR54636, Thessaloniki, Greece.
Mult Scler Relat Disord. 2020 Jun;41:102047. doi: 10.1016/j.msard.2020.102047. Epub 2020 Mar 7.
Cognitive impairment (CI) affects about 40-70% of multiple sclerosis (MS) patients. Brain MRI explains about 33-50% of the CI variance in MS. The cognitive reserve (CR) hypothesis has been postulated to identify other factors that can account for more variance in this outcome. The objective of this study was to explore the impact of CR on cognitive performance in MS patients.
A total of 526 MS outpatients were recruited (70.9% females, 41.7 ± 11.1 years old). CR was cross-sectionally assessed by the CR Index questionnaire (CRIq). Cognitive assessment was performed using the Brief International Cognitive Assessment for Multiple Sclerosis (BICAMS) tool to evaluate information processing speed, verbal memory and visuospatial memory. The role of CRIq in MS cognition was investigated by using multiple linear regression models to account for possible confounders.
In total 202 (38.4%) patients were found with CI (i.e. failure in at least one of the three cognitive tests used based on normative data from 212 healthy controls). The CRIq score of CI patients was lower than that of non-CI patients (p < 0.001). CRIq score was significantly correlated with information processing speed (rho = 0.364, p < 0.001), verbal memory (rho = 0.237, p < 0.001) and visuospatial memory (rho = 0.331, p < 0.001), having adjusted for age and sex. CRIq was also significantly associated with disability (rho = -0.188, p < 0.001) and depressive symptoms (rho = -0.220, p < 0.001). Roughly, CRIq, disability and depressive symptoms significantly explained 12.2-23.7% of cognitive performance in MS. A significant interaction between CRIq and disability was also found for information processing speed.
CR has a protective role in MS-related cognitive dysfunction. The differential effect of CR on distinct cognitive domains is supported. Interventions targeting CR to prevent cognitive impairment in MS patients are warranted by the study findings.
认知障碍（CI）影响约 40-70%的多发性硬化症（MS）患者。脑 MRI 可解释 MS 患者 CI 变异的 33-50%。认知储备（CR）假说已被提出，以确定其他因素可以解释该结果的更多变异。本研究的目的是探讨 CR 对 MS 患者认知表现的影响。
共招募了 526 名 MS 门诊患者（70.9%为女性，41.7±11.1 岁）。CR 采用 CR 指数问卷（CRIq）进行横断面评估。使用简短国际认知评估多发性硬化症（BICAMS）工具进行认知评估，以评估信息处理速度、言语记忆和视空间记忆。使用多元线性回归模型来研究 CRIq 在 MS 认知中的作用，以考虑可能的混杂因素。
共有 202 名（38.4%）患者存在 CI（即根据 212 名健康对照者的正常数据，在三项认知测试中的至少一项失败）。CI 患者的 CRIq 评分低于非 CI 患者（p<0.001）。CRIq 评分与信息处理速度（rho=0.364，p<0.001）、言语记忆（rho=0.237，p<0.001）和视空间记忆（rho=0.331，p<0.001）显著相关，调整了年龄和性别。CRIq 也与残疾（rho=-0.188，p<0.001）和抑郁症状（rho=-0.220，p<0.001）显著相关。大约，CRIq、残疾和抑郁症状显著解释了 MS 患者认知表现的 12.2-23.7%。还发现 CRIq 与残疾之间存在显著的交互作用，对信息处理速度有影响。
CR 对 MS 相关认知功能障碍具有保护作用。支持 CR 对不同认知领域的不同影响。研究结果表明，针对 CR 的干预措施对预防 MS 患者认知障碍是必要的。
