Chronic fatigue syndrome (ME/CFS)
Myalgic encephalomyelitis or chronic fatigue syndrome (ME/CFS) is a disabling long-term illness diagnosed from a characteristic symptom pattern, especially post-exertional malaise, after assessment for alternative and coexisting conditions; management is person-led energy management and symptom support, not fixed graded exercise.
Definition
Myalgic encephalomyelitis or chronic fatigue syndrome (ME/CFS) is a disabling long-term illness characterised by debilitating fatigue, post-exertional malaise, unrefreshing sleep or sleep disturbance, cognitive difficulties and substantial functional reduction. NICE confirms the diagnosis after 3 months of the core symptom pattern when another condition does not explain it; no single diagnostic test confirms the illness.
First principles
Post-exertional malaise is central
ME/CFS is not ordinary tiredness. The defining pattern includes debilitating fatigue that is not substantially relieved by rest, post-exertional malaise after cognitive, physical, emotional or social activity, unrefreshing sleep or sleep disturbance, and cognitive difficulties. Post-exertional malaise is often delayed by hours or days, disproportionate to the activity and followed by prolonged recovery; it may occur after activity that previously felt manageable.
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