Prevalence of fatigue and its association with clinical features in progressive and non-progressive forms of Multiple Sclerosis.

BACKGROUND

Fatigue is a complex and disabling symptom of Multiple Sclerosis (MS); however, there is conflicting evidence of the relationship between fatigue and clinical features of MS. Furthermore, few studies have considered these relationships specifically in a progressive MS population.

AIMS

(1) estimate the prevalence of self-reported fatigue in people with MS; (2) evaluate the relationship between fatigue severity/impact and clinical features of MS; (3) compare the prevalence of fatigue, and the strength of relationship between fatigue severity/impact and clinical features of MS in progressive and non-progressive forms of MS.

METHODS

An online survey was conducted to measure the severity (Fatigue Severity Scale (FSS)) and impact of self-reported fatigue (Modified Fatigue Impact Scale) in people with MS. The survey also contained questionnaires related to disability, quality of life, MS impact, anxiety and depression, cognition, and sleep quality.

RESULTS

412 people responded to the survey, of which 68.7% reported having fatigue (FSS ≥ 5). The prevalence of fatigue was significantly higher in participants with progressive MS (81%) in comparison to those with non-progressive forms of MS (64%, p = 0.01). Fatigue severity and impact were associated with quality of life, MS impact, anxiety, depression, cognition, and sleep quality in both progressive and non-progressive MS populations (p < 0.05). However, fatigue severity (r = 0.335) and impact (r = 0.391) were correlated with disability only in participants with non-progressive MS.

CONCLUSION

Fatigue was more prevalent amongst participants with progressive MS. In addition, higher fatigue severity and impact were associated with greater physical, cognitive, and psychological impairment, although the strength of association between these outcomes was generally similar regardless of the type of MS.