Patients with multiple sclerosis (MS) experienced such a level of fatigue that they were willing to exchange worsening MS symptoms for fatigue relief, according to study findings published in the Multiple Sclerosis Journal.
The majority of patients with MS (~80%) report that fatigue affects their health-related quality of life, daily activities, and work productivity, and some studies have reported that fatigue was as important to patients as disease-related physical disability. In general, fatigue symptoms worsen with disease progression.
To quantify the toll fatigue has on patients with MS, researchers sourced data for this study from the Oral Ponesimod Versus Teriflunomide In Relapsing Multiple Sclerosis trial (OPTIMUM; ClinicalTrials.gov Identifier: NCT02425644) and a discrete choice experiment (DCE). The Fatigue Symptoms and Impacts Questionnaire–Relapsing Multiple Sclerosis, symptom domain (FSIQ-RMS-S) instrument was used to quantify symptoms of fatigue and to correlate symptoms of fatigue with MS relapse and progression.
The OPTIMUM trial comprised 567 patients receiving 20 mg ponesimod and 566 patients receiving 14 mg teriflunomide, and the DCE trial comprised 817 patients. These cohorts included individuals aged 18-82 years, 64.0%-77.0% were women, 91.8%-97.7% were White, the average time since diagnosis was 4.3-9.4 years, and 76.5%-97.5% had relapsing-remitting MS.
At baseline, patients who received ponesimod reported an average FSIQ-RMS-S score of 31.9 (range, 0-95.4) points and 1.7 (range, 0.5) relapses in the prior 2 years, those who received teriflunomide had an average FSIQ-RMS-S score of 32.8 (range, 0-88.4) points with 1.7 (range, 0-6) relapses, and those in the DCE cohort had a score of 54.4 (range, 0-100) points with 3.9 (range, 3-6) relapses.
Based on patient report, FSIQ-RMS-S scores of 25 points were mapped to a fatigue level corresponding with “a little difficulty”, 50 points with “moderate difficulty”, and 75 points with “quite a bit of difficulty”.
In exchange for a 3-57-point change in FSIQ-RMS-S physical fatigue scores, patients were willing to accept an increase in the rate of MS relapse by 0.06 relapses per year and a 0.15-0.17-year decrease in the time to disease progression. Similarly, for a 3.57-point change in FSIQ-RMS-S cognitive fatigue scores, patients were willing to accept 0.09-0.10 more relapses per year and a 0.24-0.28-year decrease in the time to disease progression.
These findings may have been biased as participants in both OPTIMUM and DCE reported differing baseline levels of fatigue, which may have affected correlations between fatigue and MS relapse and progression outcomes.
The results of this study suggested that patients with MS were willing to exchange disease relapse and progression for fatigue relief. The researchers concluded that “These observations highlight the level of disruption caused by fatigue and the importance of fatigue treatment to people living with MS.”
Disclosure: Multiple authors declared affiliations with industry. Please refer to the original article for a full list of disclosures.
Fox RJ, Tervonen T, Phillips-Beyer A, et al. The relevance of fatigue to relapse rate in multiple sclerosis: Applying patient preference data to the OPTIMUM trial. Mult Scler. Published online December 22, 2022. doi:10.1177/13524585221140270