Characterizing Fatigue by Multiple Sclerosis Subtype and Determining Validity of a Fatigue Scale Specific to Persons...

Area of Science:

• Neurology
• Clinical Research
• Patient-Reported Outcomes

Background:

• Fatigue is a significant and disabling symptom in multiple sclerosis (MS).
• Progressive MS (PMS) patients report higher fatigue prevalence than relapsing MS (RRMS) patients.
• Existing fatigue assessment tools lack specific validation for PMS, despite distinct symptom characterization.

Purpose of the Study:

• To characterize fatigue differences between RRMS and PMS subtypes.
• To determine the convergent validity of the Fatigue Symptoms and Impacts Questionnaire (FSIQ) in PMS patients.

Main Methods:

• A nationwide survey collected data from 806 participants (637 RRMS, 169 PMS).
• Data included demographics, disease severity, fatigue, quality of life, and functioning.
• Convergent validity of FSIQ was assessed using correlation analyses.

Main Results:

• PMS patients reported significantly higher fatigue severity than RRMS patients (P < .001).
• FSIQ subdomains (physical, cognitive/emotional, coping) showed moderate to excellent validity (r = 0.5-0.75, r > 0.75) with other fatigue measures (P < .001).

Conclusions:

• Elevated fatigue in PMS highlights the need for validated assessment tools.
• The FSIQ is a valid, freely available instrument for measuring physical, mental, and emotional fatigue in PMS.