Use of composite scores in the quantification of deterioration in multiple sclerosis

Harmonizing Definitions for Progression Independent of Relapse Activity in Multiple Sclerosis: A Systematic Review

Importance

Emerging evidence suggests that progression independent of relapse activity (PIRA) is a substantial contributor to long-term disability accumulation in relapsing-remitting multiple sclerosis (RRMS). To date, there is no uniform agreed-upon definition of PIRA, limiting the comparability of published studies.

Objective

To summarize the current evidence about PIRA based on a systematic review, to discuss the various terminologies used in the context of PIRA, and to propose a harmonized definition for PIRA for use in clinical practice and future trials.

Evidence Review

A literature search was conducted using the search terms multiple sclerosis, PIRA, progression independent of relapse activity, silent progression, and progression unrelated to relapses in PubMed, Embase, Cochrane, and Web of Science, published between January 1990 and December 2022.

Findings

Of 119 identified single records, 48 eligible studies were analyzed. PIRA was reported to occur in roughly 5% of all patients with RRMS per annum, causing at least 50% of all disability accrual events in typical RRMS. The proportion of PIRA vs relapse-associated worsening increased with age, longer disease duration, and, despite lower absolute event numbers, potent suppression of relapses by highly effective disease-modifying therapy. However, different studies used various definitions of PIRA, rendering the comparability of studies difficult.

Conclusion and Relevance

PIRA is the most frequent manifestation of disability accumulation across the full spectrum of traditional MS phenotypes, including clinically isolated syndrome and early RRMS. The harmonized definition suggested here may improve the comparability of results in current and future cohorts and data sets.

Teleneurology in patients with multiple sclerosis: EDSS ratings derived remotely and from hands-on examination

We compared the telemedicine assessment of 20 patients with multiple sclerosis (MS) with the findings of a hands-on examiner. The remote specialist was a neurologist with expertise in MS; the hands-on examination was performed by an experienced mid-level practitioner. We also compared the findings of a second specialist viewing the examination in the room with the patient. The videoconference link operated at a bandwidth of 384 kbit/s. All three examiners independently completed a standardized rating scale for neurological functions. Cronbach's alpha for the three raters' total expanded disability status scale (EDSS) score was 0.99 with individual correlations ranging from 0.96-0.97. Agreement between raters for individual neurological domain scores was more variable. The most consistent assessments were for optic, bowel and bladder, and cerebral functions. The least consistent were for cerebellar and brain stem functions. Agreement between the remote and local examiners was similar to that reported for different neurological examiners directly assessing the same patient using the EDSS rating system.

Day-to-day variability of maximum walking distance in MS patients can mislead to relevant changes in the Expanded Disability Status Scale (EDSS): average walking speed is a more constant parameter

In this preliminary study we measured maximum walking distance and walking time on four consecutive days in 29 patients with clinically stable multiple sclerosis (MS). Patients were included in the study if they could achieve a maximum unaided walking distance of 100 up to 500 m. Our results showed a certain day-to-day variability of maximum walking distance, in some cases meaning changes up to 1.5 points in the expanded disability status scale (EDSS), which could be misinterpreted as a progression of the disease. Simultaneous measurements of maximum walking time showed a similar variability, unlike the mean walking speed which turned out to be more stable. Our results therefore suggest that scoring of MS patients should not be based on one single measurement of the maximum walking distance. The more reliable parameter appears to be the mean walking speed.