Fieke S. Koopman, Merel A. Brehm, Anita Beelen, Nicole Voet, Gijs Bleijenberg, Alexander Geurts, Frans Nollet
Department of Rehabilitation , Academic Medical Center, University of Amsterdam, PO 22660, 1100 DD Amsterdam, The Netherlands. E-mail: s.koopman@amc.uva.nl
DOI: 10.2340/16501977-2247

Background: Cognitive behavioural therapy does not reduce fatigue in post-polio syndrome, but is effective in facioscapulohumeral dystrophy. This difference in efficacy might be explained by a different role of cognitions in these conditions.
Objective: To compare fatigue-related cognitions between patients with post-polio syndrome and facio-scapulohumeral dystrophy.
Subjects: Patients with post-polio syndrome (n = 21) and facioscapulohumeral dystrophy (n = 24) allocated to a cognitive behavioural therapy intervention in 2 identical trials.
Methods: Assessed cognitions included: sense of control over fatigue; catastrophizing; acceptance; focusing on fatigue; and perceived social support. Group
differences in cognitions (independent t-tests or Mann–Whitney U tests) and group differences in the association of cognitions with fatigue (linear regression models) were studied.
Results: No differences in cognitions were found between the 2 groups (p > 0. 18). Furthermore, there were no cognition-by-group interaction effects, except for “perceived social support”, for which a different association with fatigue was found between the 2 groups (p = 0. 01). However, univariate models revealed no associations per group.
Conclusion: Fatigue-related cognitions in severely fatigued patients with post-polio syndrome are not clearly different from that in facioscapulohumeral dystrophy. Thus, the lack of efficacy of cognitive behavioural therapy in post-polio syndrome cannot be attributed to unique cognitive characteristics of this population.

Post-polio syndrome (PPS) and facioscapulohumeral dystrophy (FSHD) are two different neuromuscular disorders. Fatigue is a frequent complaint in both disorders. A recent study showed that cognitive behavioral therapy (CBT), which is a type of psychotherapy that helps patients to identify and reshape thoughts and behavior patterns that contribute to the fatigue was effective in alleviating fatigue in FSHD but not in PPS. In this study we investigated whether this difference in effectiveness might be explained by dissimilar fatigue-related thoughts (for example focusing on fatigue) in both conditions. We used questionnaires to measure the fatigue-related thoughts in 21 patients with PPS and 24 patients with FSHD . It appeared that fatigue-related thoughts in PPS were similar to those in FSHD and thus do not explain the difference in effectiveness of CBT.

Appendix S1