Long-term course and morphological MRI correlates of cognitive function in multiple sclerosis

Abstract

Background: Cognitive impairment frequently occurs in patients with MS (pwMS). Magnetic resonance imaging (MRI) markers could help to identify patients at risk for decline. Objective: To characterize the long-term course and morphological MRI correlates of cognitive function in pwMS. Methods: We invited 116 pwMS who had undergone clinical, cognitive, and MRI evaluations between 2006 and 2012 (baseline, BL) to attend follow-up (FU) testing between 2016 and 2018. Disability (expanded disability status scale (EDSS)), cognition (brief repeatable battery of neuropsychological test (BRB-N)), global and regional T2-lesion load (T2-LL), brain volumes, and cortical thickness were assessed. Results: Sixty-three pwMS were willing to attend the FU (54%; median EDSS = 2, interquartile range (IQR) = 2) and did not differ from non-participating pwMS regarding BL characteristics. At BL, half of the participants showed cognitive deficits in at least one domain. Across the entire group, we observed no relevant changes in physical disability and cognition over 10 years. BL thalamic volume best predicted cognitive function at FU, in addition to age and BL cognition, explaining 67% of variance. Cognitive decliners (23.8%) were older, had longer disease duration, and a tendency for lower thalamic volume at BL. Conclusion: Thalamic volume predicted FU cognitive function and distinguished declining from stable pwMS, underlining the potential of MRI to define risk groups.

Iron Rims in Patients With Multiple Sclerosis as Neurodegenerative Marker? A 7-Tesla Magnetic Resonance Study

“…Among gray matter structures, the thalamus is considered particularly susceptible to neurodegeneration through lesions within the thalamus itself, but also indirectly via the crossing demyelinated nerve tracts of the white matter and cortex, and therefore serves as a measure of diffuse parenchymal damage ( 88 ). Thalamic volume changes have been reported to be associated with cognitive impairment ( 89 – 91 ). This would be consistent with our results showing significant thalamic volume loss within 3 years in the atrophy cohort.…”

Information processing speed as a prognostic marker of physical impairment and progression in patients with multiple sclerosis

“…Test scores were transformed into standardized z-scores and adjusted for age, sex and education (Scherer et al, 2004). Cognitive impairment in one cognitive test was defined by a z-value <-1.5 (Pinter et al, 2020). (Kurtzke, 1983).…”

Slowly expanding lesions are a marker of progressive MS – Commentary

“…In this context, also cognitive function should be considered, highlighted by findings identifying thalamic volume at baseline as a predictor of cognitive function and declining MS at 10 years. 8 In summary, SELs are not ready yet to serve as a marker of progressive MS, but may characterize a relevant lesion subtype. By way of nature, they only represent a small part of the picture in a complex disease, where in addition diffuse brain and spinal cord and compartmental gray matter damage 9 and functional reorganization 10 play a role.…”