Chronic Fatigue Syndrome and Sleep Disturbance

Author: Rohan Smith | Functional Medicine Practitioner | Adelaide, SA

Quick Answer

Sleep disturbance is a core and defining feature of Chronic Fatigue Syndrome (CFS/ME). Most individuals experience non-restorative sleep, insomnia, hypersomnia, or disrupted circadian rhythms. These disturbances are not explained by poor sleep habits alone and are more commonly associated with neuroendocrine, immune, autonomic, and mitochondrial dysregulation rather than primary sleep disorders.

Core Concept: Why Sleep Is Central to CFS

Chronic Fatigue Syndrome, also referred to as Myalgic Encephalomyelitis (ME/CFS), is characterised by persistent fatigue lasting longer than six months, accompanied by post-exertional malaise, cognitive dysfunction, and unrefreshing sleep. Importantly, sleep in CFS is frequently described as non-restorative, meaning individuals wake feeling unrefreshed regardless of sleep duration.

Unlike primary insomnia, sleep disturbance in CFS reflects dysregulation of biological systems that govern circadian rhythm, stress signalling, immune communication, and cellular energy metabolism. A broader clinical overview of these patterns is explored in our chronic fatigue resource hub.

Sleep Symptoms Commonly Seen in CFS

• Insomnia: difficulty initiating or maintaining sleep
• Hypersomnia: excessive sleep duration or pronounced daytime sleepiness
• Non-restorative sleep: waking unrefreshed despite adequate sleep opportunity
• Circadian rhythm disruption: delayed sleep phase or irregular sleep–wake cycles
• Sleep-disordered breathing: including obstructive sleep apnoea in a subset of individuals

Why Does CFS Affect Sleep?

HPA Axis Dysregulation

The hypothalamic–pituitary–adrenal (HPA) axis regulates cortisol secretion and circadian rhythm. In CFS, altered diurnal cortisol patterns have been observed, which may impair sleep initiation, reduce slow-wave sleep, and contribute to early-morning waking. These changes appear functional rather than structural and may reflect chronic stress signalling rather than adrenal failure. A deeper discussion of this physiology is outlined in our overview of HPA axis dysregulation in chronic fatigue.

Immune and Neuroinflammatory Signalling

CFS is associated with immune dysregulation and altered cytokine activity. Pro-inflammatory cytokines such as interleukin-1β and tumour necrosis factor-α are known to influence sleep architecture. Persistent immune activation may therefore disrupt sleep continuity and contribute to the experience of unrefreshing sleep. Immune signalling is closely connected to the gut–immune axis, which may further influence sleep and fatigue patterns.

Autonomic Nervous System Imbalance

Many individuals with CFS exhibit autonomic dysfunction, including sympathetic overactivation and reduced parasympathetic tone. This chronically hyper-aroused physiological state can interfere with sleep onset, sleep depth, and overnight recovery, even in the absence of overt psychological stress. These patterns frequently overlap with presentations discussed in our mental health and nervous system regulation resources.

Mitochondrial and Energy Metabolism Dysfunction

Mitochondria play a central role in cellular energy production and circadian regulation. Emerging evidence suggests altered mitochondrial function in CFS, which may impair nocturnal cellular repair processes and contribute to persistent fatigue despite adequate sleep duration. Related metabolic contributors are discussed further in our resource on methylation and cellular energy regulation.

How Is Sleep Addressed in CFS?

There is no single intervention that resolves sleep disturbance in CFS. Management focuses on identifying contributing biological drivers while supporting sleep regulation and circadian stability.

Sleep Hygiene and Circadian Support

Foundational sleep hygiene strategies include consistent sleep–wake timing, appropriate light exposure, avoidance of stimulants later in the day, and creating a low-arousal sleep environment. While rarely sufficient in isolation, these measures support circadian entrainment.

Cognitive Behavioural Therapy for Insomnia (CBT-I)

CBT-I may improve sleep efficiency and reduce insomnia severity in some individuals with CFS. Importantly, CBT-I targets sleep-related behaviours rather than the underlying disease process and should be applied cautiously to avoid symptom exacerbation.

Nutrient and Neurochemical Support

Certain nutrients and compounds, such as melatonin, glycine, or magnesium-based interventions, may support sleep regulation in selected individuals. These should be used under professional guidance, particularly given the altered supplement sensitivity commonly reported in CFS.

When to Consider Functional Testing

Persistent sleep disturbance despite behavioural interventions may warrant further assessment. Functional evaluation may explore circadian cortisol patterns, autonomic balance, nutrient status, mitochondrial metabolism, or contributing gut–immune factors, depending on the clinical presentation. Testing options are outlined in our broader functional testing services.

Next Steps

Sleep disturbance in Chronic Fatigue Syndrome is not a secondary complaint—it is a central feature of the condition. Meaningful improvement often requires an integrated approach that recognises the complex neuroimmune and metabolic drivers involved.

If you are experiencing chronic fatigue with unrefreshing sleep and routine investigations have been unremarkable, a functional medicine approach may help clarify contributing mechanisms and guide personalised support.

Key Insights

• Unrefreshing sleep is a defining feature of CFS/ME
• Sleep disturbance reflects systemic dysregulation rather than poor sleep habits alone
• HPA axis, immune signalling, autonomic balance, and mitochondrial function all influence sleep quality
• Management focuses on regulation and support, not cure

Book a Consultation

If you are looking for a functional medicine practitioner or chronic fatigue specialist in Adelaide, Elemental Health and Nutrition offers comprehensive assessment and personalised care for complex fatigue presentations.

References

1. Institute of Medicine. Beyond Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: Redefining an Illness. National Academies Press; 2015.
2. Jason LA, et al. Unrefreshing sleep in ME/CFS. Journal of Health Psychology. 2011.
3. Clauw DJ. Perspectives on fatigue from chronic fatigue syndrome. Journal of Rheumatology. 2000.
4. Van Cauwenbergh D, et al. Sleep disturbances in chronic fatigue syndrome. Clinical Rehabilitation. 2014.
5. Cleare AJ. The HPA axis and chronic fatigue syndrome. Endocrine Reviews. 2003.
6. Torres-Harding S, et al. Neuroendocrine abnormalities in CFS. Biological Psychology. 2008.
7. Morris G, Maes M. Immune-inflammatory pathways in ME/CFS. Neuro Endocrinology Letters. 2013.
8. Montoya JG, et al. Cytokine signature associated with disease severity in CFS. PNAS. 2017.
9. Newton JL, et al. Autonomic dysfunction in chronic fatigue syndrome. QJM. 2007.
10. Wyller VB, et al. Sympathetic nervous system activity in CFS. European Journal of Neurology. 2008.
11. Myhill S, et al. Mitochondrial dysfunction in chronic fatigue syndrome. International Journal of Clinical and Experimental Medicine. 2009.
12. Naviaux RK, et al. Metabolic features of chronic fatigue syndrome. PNAS. 2016.
13. Jackson ML, et al. Sleep disturbances in chronic fatigue syndrome. Sleep Medicine Reviews. 2015.
14. Mitchell AJ, et al. CBT for insomnia in chronic illness. Sleep Medicine Clinics. 2019.
15. Brzezinski A. Melatonin in humans. New England Journal of Medicine. 1997.
16. Yamadera H, et al. Glycine ingestion improves sleep quality. Sleep and Biological Rhythms. 2007.