Fatigue, Sleep, and Autoimmune and Related Disorders.
Zielinski, Mark R, Systrom, David M, Rose, Noel R · Frontiers in immunology · 2019 · DOI
Quick Summary
Severe fatigue is one of the most disabling symptoms reported by people with autoimmune diseases, including ME/CFS. This review examines how inflammation and the brain contribute to fatigue in these conditions. The authors explain that fatigue involves multiple body systems—including energy supply, metabolism, mood, and sleep—all of which can be disrupted by inflammation.
Why It Matters
This review provides a comprehensive framework for understanding why ME/CFS patients experience profound, disproportionate fatigue and why this symptom is so difficult to treat. By highlighting inflammation and CNS dysfunction as central mechanisms, it validates patient experiences and suggests multiple potential therapeutic targets for future research and clinical intervention.
Observed Findings
Fatigue is the most common symptom across multiple autoimmune diseases including ME/CFS, MS, SLE, RA, celiac disease, and type 1 diabetes.
Fatigue episodes vary in severity and duration but can severely impair simple activities such as climbing stairs or crossing a room.
Physiological processes implicated in fatigue include oxygen/nutrient supply, metabolism, mood, motivation, sleep, and central nervous system function.
Inflammation affects multiple systems known to contribute to fatigue.
The central nervous system is impacted directly or indirectly in numerous autoimmune and related disorders, contributing to fatigue.
Inferred Conclusions
Fatigue in autoimmune diseases is multifactorial and involves dysfunction across multiple physiological systems rather than a single mechanism.
Inflammation serves as a common pathophysiological link affecting oxygen delivery, metabolism, mood regulation, and CNS function in fatigue.
The central nervous system plays a critical role in fatigue pathophysiology and represents an important therapeutic target.
Understanding fatigue requires integration of peripheral inflammatory mechanisms with central neurobiological processes.
Remaining Questions
What This Study Does Not Prove
This review does not establish specific biomarkers or prove causal mechanisms of fatigue in any single disease. As a narrative/systematic review, it synthesizes existing literature rather than providing new experimental data, and it does not determine whether inflammation causes CNS dysfunction in fatigue or vice versa. The study also does not quantify the relative contribution of each proposed mechanism to overall fatigue severity.
About the PEM badge: “PEM required” means post-exertional malaise was an explicit required diagnostic criterion for participant inclusion in this study — not that PEM was studied, observed, or discussed. Studies using criteria that do not require PEM (e.g. Fukuda, Oxford) are tagged “PEM not required”. How the atlas works →