BACKGROUND: Although there is evidence that shows worse cognitive functioning in male patients with multiple sclerosis (MS), the role of brain pathology in this context is under-investigated. OBJECTIVE: To investigate sex differences in cognitive performance of MS patients, in the context of brain pathology and disease burden. METHODS: Brain MRI, neurological examination, neuropsychological assessment (Brief International Cognitive Assessment in MS-BICAMS, and Paced Auditory Verbal Learning Test-PASAT), and patient-reported outcome questionnaires were performed/administered in 1052 MS patients. RESULTS: Females had higher raw scores in the Symbol Digit Modalities Test (SDMT) (57.0 vs. 54.0; p < 0.001) and Categorical Verbal Learning Test (CVLT) (63.0 vs. 57.0; p < 0.001), but paradoxically, females evaluated their cognitive performance by MS Neuropsychological Questionnaire as being worse (16.6 vs 14.5, p = 0.004). Females had a trend for a weaker negative correlation between T2 lesion volume and SDMT ([Formula: see text] = - 0.37 in females vs. - 0.46 in men; interaction p = 0.038). On the other hand, women had a trend for a stronger correlation between Brain Parenchymal Fraction (BPF) and a visual memory test (Spearman's [Formula: see text] = 0.31 vs. 0.21; interaction p = 0.016). All these trends were not significant after correction for false discovery rate. CONCLUSIONS: Although, females consider their cognition as worse, males had at a group level slightly worse verbal memory and information processing speed. However, the sex differences in cognitive performance were smaller than the variability of scores within the same sex group. Brain MRI measures did not explain the sex differences in cognitive performance among MS patients.

• Keywords
• Brain atrophy, Cognition, Lesion volume, MRI, Multiple sclerosis, Sex,
• MeSH
• Cognition MeSH
• Cognitive Dysfunction * MeSH
• Cognition Disorders * diagnosis   MeSH
• Humans MeSH
• Magnetic Resonance Imaging MeSH
• Brain diagnostic imaging   MeSH
• Neuropsychological Tests MeSH
• Sex Characteristics MeSH
• Multiple Sclerosis * complications   diagnostic imaging   MeSH
• Check Tag
• Humans MeSH
• Male MeSH
• Female MeSH
• Publication type
• Journal Article MeSH

(1) Background: Cognitive deterioration is an important marker of disease activity in multiple sclerosis (MS). It is vital to detect cognitive decline as soon as possible. Cognitive deterioration can take the form of isolated cognitive decline (ICD) with no other clinical signs of disease progression present. (2) Methods: We investigated 1091 MS patients from the longitudinal GQ (Grant Quantitative) study, assessing their radiological, neurological, and neuropsychological data. Additionally, the confirmatory analysis was conducted. Clinical disease activity was defined as the presence of new relapse or disability worsening. MRI activity was defined as the presence of new or enlarged T2 lesions on brain MRI. (3) Results: Overall, 6.4% of patients experienced cognitive decline and 4.0% experienced ICD without corresponding clinical activity. The vast majority of cognitively worsening patients showed concomitant progression in other neurological and radiologic measures. There were no differences in disease severity between completely stable patients and cognitively worsening patients but with normal cognition at baseline. (4) Conclusions: Only a small proportion of MS patients experience ICD over short-term follow-up. Patients with severe MS are more prone to cognitive decline; however, patients with normal cognitive performance and mild MS might benefit from the early detection of cognitive decline the most.

• Keywords
• MRI, cognition, cognitive decline, disability, disease activity monitoring, isolated cognitive decline, multiple sclerosis, relapse,
• Publication type
• Journal Article MeSH

BACKGROUND: Cognitive deficits are common in early multiple sclerosis (MS), however, spatial navigation changes and their associations with brain pathology remain poorly understood. OBJECTIVE: To characterize the profile of spatial navigation changes in two main navigational strategies, egocentric (self-centred) and allocentric (world-centred), and their associations with demyelinating and neurodegenerative changes in early MS. METHODS: Participants with early MS after the first clinical event (n = 51) and age-, gender- and education-matched controls (n = 42) underwent spatial navigation testing in a real-space human analogue of the Morris water maze task, comprehensive neuropsychological assessment, and MRI brain scan with voxel-based morphometry and volumetric analyses. RESULTS: The early MS group had lower performance in the egocentric (p = 0.010), allocentric (p = 0.004) and allocentric-delayed (p = 0.038) navigation tasks controlling for age, gender and education. Based on the applied criteria, lower spatial navigation performance was present in 26-29 and 33-41% of the participants with early MS in the egocentric and the allocentric task, respectively. Larger lesion load volume in cortical, subcortical and cerebellar regions (ß ≥ 0.29; p ≤ 0.032) unlike brain atrophy was associated with less accurate allocentric navigation performance. CONCLUSION: Lower spatial navigation performance is present in up to 41% of the participants with early MS. Demyelinating lesions in early MS may disrupt neural network forming the basis of allocentric navigation.

• Keywords
• Allocentric, Cognition, Egocentric, Lesion load, MRI, Neuropsychology, Volumetry, Voxel-based morphometry,
• MeSH
• Cognition MeSH
• Cognitive Dysfunction * MeSH
• Humans MeSH
• Neuropsychological Tests MeSH
• Spatial Navigation * MeSH
• Multiple Sclerosis * diagnostic imaging   MeSH
• Space Perception MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH