With the proposal of the Brief International Cognitive Assessment for Multiple Sclerosis (BICAMS) battery, the need to screen for cognitive deficits within standard clinical care of patients with multiple sclerosis (MS) has been acknowledged. Data regarding how patient characteristics might predict low cognitive performance and therefore require particularly close monitoring is, however, limited so far. We investigated a large, nationwide patient cohort from ambulatory settings, representing the typical distribution of different subtypes, levels of physical disability, and disease durations. Besides cognitive testing with BICAMS, additional sampling of multiple demographics and clinical variables allowed us to characterize general and domain‐specific prevalence patterns of cognitive impairment (CI) as well as to delineate which factors are associated with cognitive performance. In a total of 1,094 patients, CI was present in 28% (using a conservative cut‐off of the 5th percentile below normative values), with information‐processing speed being most frequently affected. Impairment was overall higher in patients with primary progressive (PPMS) and secondary progressive MS than in patients with relapsing–remitting (RR)MS. Regression modelling revealed that disease subtype (i.e., PPMS), long disease duration, high physical disability, unemployment, low educational level, high age, male sex, and the absence of current disease‐modifying treatment were important predictors for worse BICAMS’ test performance. These results emphasize the importance of continuous cognitive assessment during regular neurological follow‐up visits, with a particular focus on patients being identified as high‐risk subjects for CI according to the reported factors.

ObjectiveRetinal layer thickness (RLT) measured by optical coherence tomography (OCT) is considered a noninvasive, cost-efficient marker of neurodegeneration in multiple sclerosis (MS). We aimed to investigate associations of RLT with cognitive performance and its potential as indicator of cognitive status in patients with MS by performing generalized estimating equation (GEE) analyses.MethodsIn this cross-sectional study, patients with at least mild signs of cognitive impairment were examined by OCT as well as by the Brief International Cognitive Assessment for MS and tests assessing attention and executive functions (Trail Making Test [TMT] A and B). Associations of these factors were investigated using GEE models controlling for demographic and disease-related factors and correcting for multiple testing.ResultsA total of 64 patients entered the study. In the final sample (n = 50 [n = 14 excluded due to missing data or drop-outs]; n = 44 relapsing-remitting MS and n = 6 secondary progressive MS, mean Expanded Disability Status Scale score = 2.59 [SD = 1.17], disease duration [median] = 7.34 [interquartile range = 12.1]), 36.0% were cognitively impaired. RLT of the macular retinal nerve fiber layer was associated with performance in TMT-B (β = −0.259). Analyses focusing on the upper and lower tertile of RLT additionally revealed associations between macular ganglion cell-inner plexiform layer and TMT-B and verbal short-term memory and learning, respectively.ConclusionIn patients with MS, at less advanced disease stages, RLT was especially associated with cognitive flexibility promoting OCT as a potential marker advocating further extensive neuropsychological examination.

ObjectiveTo explore the hypothesis that serum neurofilament light chain (sNfL) indicative of neuroaxonal damage may improve precise disease profiling with regard to cognition and neuropsychiatric symptoms, we analyzed potential associations of sNfL levels with cognitive test scores, fatigue, depression, and anxiety.MethodsPatients with relapsing-remitting and secondary progressive MS (SPMS) underwent an elaborated assessment including MRI, various cognitive tests, and patient-reported outcomes. We determined sNfL levels by single molecule array (Simoa) assay. Relationships between sNfL, cognition, neuropsychiatric symptoms, and demographical data were analyzed using correlations, group comparisons, and regressions.ResultsIn 45 clinically stable patients with MS (Expanded Disability Status Scale = 2.73 ± 1.12, disease duration = 10.03 ± 7.49 years), 40.0% were cognitively impaired. Mean sNfL levels were 16.02 ± 10.39 pg/mL, with higher levels in the SPMS subgroup (p = 0.038). sNfL levels did reliably link neither with the investigated cognitive and affective parameters nor with fatigue levels. The only relationship found in a small subgroup of patients with SPMS (n = 7) with visuospatial learning (r = −0.950, p = 0.001) and memory (r = −0.813; p = 0.026) disappeared when further controlling for age, educational level, and sex.ConclusionsIn patients with stable MS at less advanced disease stages, sNfL did not convincingly relate to cognitive performance, fatigue, depression, or anxiety and thus may not serve as a surrogate biomarker for neuropsychological status in such populations.