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Last reviewed: 16 Mar 2025
Last updated: 31 Jul 2024

Summary

Definition

History and exam

Key diagnostic factors

  • excessive daytime sleepiness
  • cataplexy
  • hypnagogic/hypnopompic hallucinations
  • sleep paralysis

Other diagnostic factors

  • chronic fatigue or tiredness
  • poor performance at work
  • poor memory and concentration
  • car accidents
  • slurred speech
  • blurred vision
  • irregular breathing pattern
  • sleep attacks
  • fragmented nocturnal sleep
  • symptoms of other sleep disorders
  • obesity
  • status cataplecticus
  • hepatomegaly
  • paresis

Risk factors

  • low cerebrospinal fluid hypocretin
  • human leukocyte antigen (HLA)-DQB1*0602
  • Prader-Willi syndrome
  • Niemann-Pick disease type C
  • linkage to 4p13-q21
  • genes on chromosome 6 or chromosome 21
  • hypothalamic tumors
  • hypothalamic infarct/hemorrhage
  • head trauma
  • central nervous system infection
  • central nervous system arteriovenous malformations
  • multiple sclerosis
  • myotonic dystrophy

Diagnostic tests

1st tests to order

  • actigraphy and sleep diary
  • overnight polysomnography
  • multiple sleep latency test (MSLT)

Tests to consider

  • HLA typing
  • cerebrospinal fluid hypocretin-1 level
  • maintenance of wakefulness test

Treatment algorithm

Contributors

Authors

Octavian C. Ioachimescu, MD, PhD
Octavian C. Ioachimescu

Associate Professor

Emory University

Atlanta VA Medical Center

Atlanta

GA

Disclosures

OCI is an editor of a book cited in this topic.

Peer reviewers

Kumaraswamy Budur, MD

Medical Doctor

Sleep Disorders Center

Department of Psychiatry

Cleveland Clinic

Cleveland

OH

Disclosures

KB declares that he has no competing interests.

Seiji Nishino, MD, PhD

Associate Professor

Psychiatry and Behavioral Science

Stanford University School of Medicine

Stanford

CA

Disclosures

SN declares that he has no competing interests.

Kingman P. Strohl, MD, FCCP

Professor of Medicine

Director

Center for Sleep Disorders Research

Professor of Anatomy

Department of Medicine

Case Western Reserve University

Cleveland

OH

Disclosures

KPS declares that he has no competing interests.

Paul Reading, MBBS

Consultant Neurologist

James Cook University Hospital

Middlesbrough

UK

Disclosures

PR declares that he has no competing interests.

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