World Sleep Day, an annual event organised by the World Sleep Day Committee, aims to raise awareness about sleep-related issues and promote better prevention and management of sleep disorders. This year’s theme, ‘Sleep Equity for Global Health’, highlights that ‘sleep is essential to health, but measurable differences in sleep health persist across populations across the world, creating additional burdens and reinforcing health inequities’. As the vast majority of people with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) report having difficulties with sleep, the relevance of World Sleep Day is evident.
The significance of quality sleep cannot be overstated, as it directly influences day-to-day functioning and overall wellbeing. Poor sleep and sleep disorders are a public health concern because they contribute to substantial societal and individual burden. Short-term consequences include reduced attention, memory and learning, whilst long-term effects encompass health problems such as diabetes, weakened immunity, and cardiovascular conditions.
Studies reveal a correlation between poor sleep quality and diminished quality of life in ME/CFS patients. Sleep disturbances intensify existing symptoms like fatigue and cognitive dysfunction. Whilst there is ample evidence of sleep dysfunction in ME/CFS, research into underlying causes remains limited. Most studies use the Fukuda criteria for chronic fatigue syndrome (CFS) which considers post-exertional malaise (PEM) to be optional for diagnosis rather than a cardinal feature as in criteria for ME/CFS. Nevertheless, these studies serve as a starting point for future research.
Some key research areas explored in relation to CFS, include – Polysomnography (sleep studies) indicating a considerable proportion of individuals meet criteria for sleep apnoea and periodic limb movement disorder. Reduced nocturnal heart rate variability suggesting potential autonomic nervous system dysregulation during sleep, leading to unrefreshing sleep. Differences in deep sleep, with reduced slow wave activity observed in CFS participants compared to healthy controls.
Whilst NICE guidelines recommend personalised sleep management strategies for individuals with ME/CFS, considering the possibility of underlying sleep disorders, the committee recognised the challenge of providing advice due to the lack of evidence and consensus in this complex area. World Sleep Day is an opportunity to talk about sleep inequities globally and emphasise the need for targeted research, including into conditions such as ME/CFS.
