To synthesize current knowledge on narcolepsy as an immune-mediated hypothalamic encephalopathy, emphasizing the synthesis of evidence across immunology, genetics, pathology, systems neuroscience, diagnosis, and therapeutics, and propose a framework for precision sleep medicine.
Key Findings:
Narcolepsy is increasingly recognized as a multisystem hypothalamic encephalopathy rather than merely a disorder of excessive sleepiness and cataplexy.
The selective loss of orexin neurons is linked to immune-mediated pathophysiology, with evidence of autoreactive T cells targeting these neurons.
Current diagnostic frameworks are inadequate, as cataplexy is not always present and cerebrospinal fluid orexin deficiency may be absent in some phenotypes, challenging traditional classifications.
Mechanism-directed therapies, such as orexin receptor agonists, show promise in addressing the underlying neurotransmitter deficit.
Interpretation:
Narcolepsy should be viewed as a model disorder that highlights the complex interplay between sleep, emotion, and immunity, necessitating a shift toward a phenotype–biomarker–mechanism stratification model in diagnosis and treatment.
Limitations:
The narrative review format may not capture all quantitative outcomes or systematic data, potentially limiting the comprehensiveness of findings.
Emerging therapies are still in clinical trials, and long-term efficacy and safety remain to be fully established.
Conclusion:
Narcolepsy represents a critical intersection of neuroimmunology and sleep medicine, warranting a comprehensive understanding and innovative therapeutic approaches.
