The present study will investigate the correlation between objective and subjective cognition in multiple sclerosis. The study will also investigate the impact of covariates such as fatigue and depression, the relationship with the Expanded Disability Status Scale (EDSS) and brain volumetrics as measured on magnetic resonance imaging (MRI). Additionally, the study will provide insights into patients' experiences with cognition, and the usability of the used objective cognitive assessments.

Cognitive impairment is a significant burden that affects 43 to 70% of persons with multiple sclerosis (pwMS) 1. Cognitive problems have been observed in the earliest stages of multiple sclerosis (MS) and multiple studies have provided evidence for the predictive value of early cognitive impairment for future disease progression 2-6. However, cognitive function is not often discussed with pwMS or routinely assessed by healthcare providers (HCPs) leading to sub-optimal treatment of cognitive problems in MS 7. Furthermore, cognitive dysfunction that can be reliably detected by objective measures is poorly recognized by pwMS, resulting in a disconnect between objective and subjective measures of cognitive function 8-10.

The present study will investigate the correlation between what cognitive problems people with MS perceive and what objective cognitive testing actually shows. This study will also provide insights about the presence of this disconnect in different strata of the Expanded Disability Status Scale (EDSS) 11, and the relationship with possible confounders (MS symptoms, fatigue, etc.) and brain volumetrics as measured on magnetic resonance imaging (MRI).

Study Design:

CogMS is an observational, cross-sectional, remote, real-world study of cognitive function in patients with multiple sclerosis. We will investigate the correlation between subjective and objective patient self-evaluations of cognitive function while also investigating the prevalence of objective cognitive impairment in different EDSS strata of pwMS. MS patients will be stratified by EDSS to evaluate the correlation between objective and subjective cognition in three different EDSS strata (EDSS 0 - 2; 2.5 - 3.5; 4.0 - 5.5) and the occurrence of objective cognitive dysfunction in these EDSS stages of MS.

All data will be captured using the icompanion app in a remote, non-clinical setting (i.e., patient's home) within three weeks of patient onboarding. In the icompanion app, patients will be asked to perform the icognition cognitive test battery together with patient-reported outcomes (PROs) for subjective cognition, MS symptoms, prEDSS, depression and fatigue. If available, a recent (max. 6 months) MRI scan will be provided from which volumetric measurements can be calculated using icometrix' icobrain software.

Finally, patients will be asked to answer questions on their experiences with cognition since diagnosis, their preferences and opinions about cognition as a treatment goal, and the usability of the icognition battery, and the preference compared to paper-based neuropsychological tests.

Inclusion Criteria:

• Providing a signed informed consent
• Aged between 18 and 65 years old
• MS diagnosis (CIS, RRMS)
• Absence of hand function problems which limit the use of a device like a smartphone
• No history of relapse with onset 30 days prior to start of study
• No other major neurological or psychiatric disorders
• No history of cognitive rehabilitation treatment

Exclusion Criteria:

• Disease duration longer than 15 years
• Patients with established cognitive disorders other than MS
• Drug and/or alcohol abuse

300 CIS/RRMS patients, aged 18 to 65 (inclusive), with a maximum disease duration of 15 years.