Cognitive reserve

[Petr75]

2019 Feb 14
Department of Psychology, University of Campania "Luigi Vanvitelli", Caserta, Italy
Does cognitive reserve play any role in multiple sclerosis? A meta-analytic study
https://www.ncbi.nlm.nih.gov/pubmed/30852304

Abstract
BACKGROUND:
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.
METHODS:
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.
RESULTS:
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.
CONCLUSION:
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.

[Petr75]

2019 Oct 21
Department NEUROFARBA, Section of Neurosciences, University of Florence, Florence, Italy
Cognitive impairment in multiple sclerosis: An exploratory analysis of environmental and lifestyle risk factors.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6802833/

Abstract
BACKGROUND:
Many potentially modifiable risk factors for MS are investigated. It is not known, however, if these factors also apply to MS-related cognitive impairment (CI), a frequent consequence of MS.
OBJECTIVE:
The aim of our study was to assess risk factors for CI in MS patients, focusing on environmental exposures, lifestyle and comorbidities.
METHODS:
We included MS patients referring to MS Centers in Florence and Barletta between 2014 and 2017. Neuropsychological performance was assessed through the Rao's battery and Stroop test, cognitive reserve (premorbid intelligence quotient-IQ) was evaluated using the National Adult Reading Test (NART). Potential risk factors were investigated through a semi-structured questionnaire.
RESULTS:
150 patients were included. CI was detected in 45 (30%) subjects and was associated with older age (p<0.005), older age at MS onset (p = 0.016), higher EDSS score (p<0.005), progressive disease course (p = 0.048) and lower premorbid IQ score (p<0.005). As for risk factors, CI was related with lower physical activity in childhood-adolescence (p<0.005). In women, hormonal therapy resulted to be protective against CI (p = 0.041). However, in the multivariable analysis, the only significant predictors of CI were older age (p<0.05; OR 1.06, 95% CI 1.02-1.10) and lower premorbid IQ (p<0.05; OR 0.93, 95% CI: 0.88-0.98). Removing IQ from the model, CI was associated with higher EDSS (p = 0.030; OR 1.25, 95% CI 1.02-1.53) and, marginally, previous physical activity (p = 0.066; OR 0.49, 95% CI: 0.23-1.05).
CONCLUSIONS:
Our findings suggest that physical activity in childhood-adolescence could be a contributor to cognitive reserve building, thus representing a potential protective factors for MS-related CI susceptible to preventive strategies.