Indre Bileviciute-Ljungar, Marie-Louise Schult, Kristian Borg, Jan Ekholm
Department of Clinical Sciences, Karolinska Institutet, Danderyd University Hospital, Stockholm, Sweden. E-mail. indre.ljungar@ki.se
DOI: 10.2340/16501977-2697

Objective: To create and evaluate a preliminary ICF Core Set for myalgic encephalomyelitis/chronic fatigue syndrome using a team-based approach.
Design: Observational study.
Subjects/patients: A total of 100 consecutive patients (mean age 45 years (standard deviation (SD) 9 years)) were assessed by a rehabilitation team and included in the study.
Methods: A preliminary International Classification of Functioning, Disability and Health (ICF) Core Set was created, based on literature studies, and on discussion forums between the team and the researchers. Patients were assessed by a rehabilitation medicine team regarding impairments in body function, activity limitations, and restrictions in participation.
Results: Clinical assessments of the component Body Functions found impairments in energy, fatigue, physical endurance, fatigability, sleep and pain in 82–100% of patients. At least half of the patients had impairments in higher cognitive functions, attention, and emotions, as well as sound and light hypersensitivity, general hyper-reactivity and thermoregulatory functions. For the component Activity/Participation, the most frequent limitations and restrictions were in doing housework (93%), assisting others (92%), acquisition of goods and services (90%), remunerative employment (87%), handling stressful situations (83%), preparing food (83%), recreation and leisure (82%), informal socializing (78%) and carrying out daily activities (77%). The most frequent degrees of impairments/limitations/restrictions assessed were light and moderate, except for remuneative employment, for which restrictions were severe.
Conclusion: Using unconventional methods, this study sets out a preliminary ICF Core Set list for patients with myalgic encephalomyelitis/chronic fatigue syndrome. Further studies are required to improve and test this Core Set in myalgic encephalomyelitis/chronic fatigue syndrome populations.

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a disabling condition with no diagnostic or prognostic markers. The patient group is heterogeneous, and impairments in functioning and disability vary between patients. The International Classification of Functioning, Disability and Health (ICF) is a well-established method to assess patient’s functioning and disability. This study sets out a preliminary ICF Core Set for ME/CFS in rehabilitation medicine. However, this requires improvement, and approval by research society and clinicians working with ME/CFS. The introduction of post-exertional malaise as a new category in the ICF should also be considered.

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