Associations between fatigue impact and physical and neurobehavioural factors: An exploration in people with progressive multiple sclerosis

The sample comprised 308 pwPMS (62 % female, 27 % primary progressive, 73 % secondary progressive), mean age 52.5 ± 7.2 yrs, median EDSS score 6.0 (4.5-6.5), mean MFIS_Total 44.1 ± 17.1, with 67.2 % categorised as fatigued. Fatigued participants walked shorter distances (6MWT, p = 0.043), had worse MSWS-12 scores (p < 0.001), and lower average % in MVPA (p = 0.026). The magnitude of associations was mostly weak between MFIS_Total and physical measures (r = 0.13 to 0.18), apart from the MSWS-12 where it was strong (r = 0.51). The magnitude of correlations were strong between the MFIS_Total and neurobehavioural measures of anxiety (r = 0.56), depression (r = 0.59), and measures of disease impact (MSIS-physical r = 0.67; MSIS-mental r = 0.71). This pattern was broadly similar for the MSIF subscales. The multivariable model indicated a five-point increase in MSWS-12 was associated with a 14 % increase in the odds of being fatigued (OR [95 %CI]: 1.14 [1.07-1.22], p < 0.0001) CONCLUSION: Management of fatigue should consider both physical and neurobehavioural factors, in cognitively impaired persons with progressive MS.