By K. Ickmans et al.
BACKGROUND: Both good physical and cognitive functioning have a positive influence on the execution of activities of daily living. Patients with chronic fatigue syndrome (CFS) as well as patients with fibromyalgia (FM) have marked cognitive deficits. Furthermore, a good physical and functional health status may have a positive impact on a variety of cognitive skills. A link that has already been observed in young and old healthy individuals, but in patients with CFS evidence is limited.
OBJECTIVE: To examine whether recovery of upper limb muscle function could be a significant predictor of cognitive performance in patients with CFS and CFS with comorbid FM. Furthermore, this study determined whether cognitive performance is different in CFS patients with and without comorbid FM.
DESIGN: A case-control design.
METHODS: Eighteen patients with CFS-only, 30 patients with CFS+FM, and 30 healthy inactive controls were studied. Participants first completed three performance-based cognitive tests designed to assess selective and sustained attention, cognitive inhibition, and working memory capacity. Seven days later, they performed a fatiguing upper limb exercise test with subsequent recovery measures.
RESULTS: Recovery of upper limb muscle function was found to be a significant predictor of cognitive performance in patients with CFS. Patients with CFS+FM, but not patients with CFS-only showed significantly decreased cognitive performance compared with the controls.
LIMITATIONS: The cross-sectional nature of this study does not allow for inferences of causation.
CONCLUSIONS: The results suggest that a better physical health status could predict better mental health in patients with CFS. Furthermore, they underline disease heterogeneity, suggesting that reducing this in future research is important to better understand and uncover mechanisms regarding the nature of divers impairments in these patients.
Source: Ickmans K, Meeus M, De Kooning M, Lambrecht L, Pattyn N, Nijs J. Can Recovery of Peripheral Muscle Function Predict Cognitive Task Performance in Chronic Fatigue Syndrome With and Without Fibromyalgia? Phys Ther. 2013 Dec 20. [Epub ahead of print]