Article

Fatigue is a debilitating symptom in multiple sclerosis (MS).
Previous studies showed no association between fatigue as perceived by the
patient and physiological measures of fatigability. OBJECTIVE: The authors
investigated associations between perceived fatigue and measures of fatigability
after correction for differences in maximal voluntary contraction (MVC). METHODS:
A total of 20 people with relapsing-remitting MS with an Extended Disability
Severity Score less than 5.5 and 20 healthy controls filled out the Fatigue
Severity Score questionnaire of perceived fatigue. The authors obtained the MVC
from the first dorsal interosseus muscle, voluntary muscle activation, and force
decline during a sustained MVC (124 s, muscle fatigue). RESULTS: Patients
perceived increased levels of fatigue compared with controls (P < .001). Although
patients and controls developed similar amounts of muscle fatigue during the
sustained contraction, a linear regression model that included both muscle
fatigue and MVC was positively associated with perceived fatigue in patients only
(R (2) = 0.45; P = .01). Voluntary activation during the sustained contraction
was negatively associated with perceived fatigue (R (2) = 0.25; P = .02).
CONCLUSION: The data indicate that fatigue perceived by MS patients is associated
with measures of fatigability. This observation helps in the understanding of
mechanisms underlying the increased levels of fatigue perceived by MS patients.
These data also emphasize that for comparison of fatigue-related parameters
between groups, correction for individual maximal force is essential.

Langue : ANGLAIS