Summary
Fatigue is a frequent and disabling symptom in patients with multiple sclerosis (MS). The objective of the study was to compare fatigue and sleepiness in MS, and their relationship to physical activity. Merkelbach S, Schulz H, Kölmel HW, Gora G, Klingelhöfer J, Dachsel R, Hoffmann F, Polzer U. J Neurol. 2010 Aug 18. [Epub ahead of print]
Details
The study compares fatigue and sleepiness in 80 patients with MS
and their relationship to physical activity. Interestingly, using
a combination of clinical scores, scales and questionnaires, they
found sleepiness varies to an appreciable extent independently
from fatigue. Sleepiness and fatigue converge for situations that
demand self-paced activation, while they differ for situations in
which external cues contribute to the level of activation such as
watching TV or driving a car. While fatigue correlated
significantly with age, the same wasn’t true with sleepiness. The
perceived overlapping of fatigue and sleepiness in MS as concepts
and lack of clear demarcation has proven an obstacle for research
in this field. This paper goes some way to improving our
understanding of these overlapping but distinct symptoms.