Multiple sclerosis relapses are associated with increased fatigue and reduced health-related quality of life - A post hoc analysis of the TEMSO and TOWER studies.

Background: Two pivotal phase 3 teriflunomide studies provided data on relapses, fatigue, and health-related quality of life (HRQoL) in patients with relapsing forms of multiple sclerosis (MS).

Objectives: Using pooled data from the TEMSO (NCT00134563) and TOWER (NCT00751881) studies, we investigated the association between relapse severity, and changes from baseline to Week 108 in fatigue and HRQoL outcomes.

Methods: Four definitions of relapse severity were applied in this analysis: sequelae post-relapse; relapse leading to hospitalization; relapse requiring intravenous corticosteroids; and intense relapse. We assessed the association between relapse severity and changes in Fatigue Impact Scale score (n=959), physical and mental health component summary scores from the Short Form (SF)-36 questionnaire (n=904), and SF-6D utility index scores (n=820).

Results: Irrespective of the definition of relapse severity applied, in patients experiencing severe relapse(s), fatigue was increased and HRQoL was decreased; these changes were statistically significant (p<0.0001), and were also clinically significant in many cases. The greatest worsening in fatigue and HRQoL was observed in patients with relapses leading to hospitalization.

Conclusions: Given that severe relapses adversely affect patient-reported fatigue and HRQoL, prevention of severe relapses should be an important therapeutic aim in the treatment of patients with MS.