The MSReactor cognitive platform can detect changes in psychomotor, attention and working memory reaction time performance in progressive MS patients.

Abstract

Introduction:Existing measures of progression in multiple sclerosis (MS) are unidimensional and weighted towards ambulation. The lack of sensitive markers of disease progression in the absence of inflammatory relapses has hindered the development of treatment options for progressive MS. MSReactor is a web-based cognitive platform that is acceptable to patients and sensitive to changes in neurological disability. Identification of sensitive measures of progression in MS will result in earlier detection and better definitions of disease progression. Objectives/Aims:To determine the sensitivity of the MSReactor tests to measure changes in cognitive performance in progressive MS. Method(s):MSReactor incorporates simple reaction time (SRT), choice reaction time (CRT) and one back tasks (OBK) measuring broad cognitive domains of information processing speed, attention and working memory, respectively. MSReactor tests were completed approximately 6-monthly at routine outpatient visits, with the option of additional tests remotely. Baseline clinical data (Expanded Disability Status Scale (EDSS) and MS duration) was collected by treating physicians during routine follow up. Change in cognitive performance was calculated in participants with progressive MS (pwpMS) who had completed more than 2 MSReactor sessions. Participants were divided into quartiles based on cognitive performance change and clinical characteristics described. Difference in cognitive change between quartiles was analysed with the Mann-Whitney-Wilcoxon test. Result(s):Fifty-six pwpMS completed testing over 787 days (median, interquartile range (IQR) 381-1596). Median test number was 7 (IQR 4-14). For all tests, at least 50% of the cohort displayed worsening reaction times. The quartile of cognitive change with greatest slowing of reaction times were significantly worse than in remaining quartiles combined, demonstrating a mean slowing in cognitive performance of 174 milliseconds (ms), 188ms and 225ms compared to -29ms, -32ms and -75ms for the SRT, CRT and OBK tasks, respectively. Thirty-eight pwpMS had EDSS scores recorded within 6 months of MSReactor testing. No significant differences in baseline EDSS or disease duration were observed between the worst performing quartile and the rest of the cohort in all tasks. Conclusion(s):In this first study, we demonstrate that MSReactor tasks can detect changes in cognitive functioning in pwpMS. This finding paves the way for larger studies to determine the trajectory of cognitive changes, and to assess the sensitivity of MSReactor to detect neurological disease progression and be considered as an outcome measure in therapy trials in progressive MS.