Obstructive sleep apnoea in adults

Last reviewed: 23 Feb 2023
Last updated: 15 Oct 2020



History and exam

Key diagnostic factors

  • obesity
  • male sex
  • maxillomandibular anomalies
  • excessive daytime sleepiness
  • episodes of apnoea
  • episodic gasping
  • restless sleep
  • insomnia
  • macroglossia
  • chronic snoring
More key diagnostic factors

Other diagnostic factors

  • cardiovascular disease
  • weight gain
  • large neck circumference
  • endocrine disorders
  • history of difficult intubation for general anaesthesia
  • family history of OSA or snoring
  • history of mucopolysaccharidoses
  • history of GORD
  • history of Down's syndrome
  • history of tooth extractions for crowding
  • history of motor vehicle accidents
  • neurocognitive dysfunction
  • mood disorders
  • nocturia
  • erectile dysfunction
  • morning headaches
  • heartburn/dyspepsia
  • dry mouth
  • nocturnal sweating
Other diagnostic factors

Risk factors

  • obesity
  • male sex
  • post-menopause (women)
  • large neck circumference
  • maxillomandibular anomalies (e.g., narrowing, retrognathia, and high, arched palate)
  • increased volume of soft tissues (includes tonsils, adenoids, and tongue)
  • family history of OSA
  • chronic snoring
  • nasal obstruction
  • polycystic ovary syndrome
  • levels of sex hormones
  • hypothyroidism
  • Down's syndrome
  • mucopolysaccharidoses
  • alcohol use
  • increasing age
  • black, Hispanic, and Asian ethnicity
  • tobacco smoking
More risk factors

Diagnostic investigations

1st investigations to order

  • polysomnography (PSG)
  • portable multichannel sleep tests
  • awake fibreoptic endoscopy
More 1st investigations to order

Emerging tests

  • cine MRI
  • drug-induced sleep endoscopy (DISE)
  • cardiovascular and neurological tests
  • biochemical or genetic signatures and assays

Treatment algorithm


Apnoea-Hypopnoea Index (AHI) or Respiratory Event Index (REI) of ≥30 episodes/hour: no discrete anatomical lesions

AHI or REI of ≥5 but <30 episodes/hour: no discrete anatomical lesions

AHI or REI of ≥5 episodes/hour with discrete anatomical lesions


persistent postoperative OSA



Ofer Jacobowitz, MD, PhD, FAASM

Co-director of Sleep

ENT and Allergy Associates

Associate Professor

Department of Otolaryngology

Northwell/Zucker School of Medicine, Hofstra University

New York



OJ is a scientific consultant for, and has received a consulting fee from, LivaNova and Nyxoah. OJ has received research support from LivaNova for US Food and Drug Administration trial research. Both LivaNova and Nyxoah have developed implantable neurostimulation systems for obstructive sleep apnoea.

Peer reviewers

Carla Daltro, MD

Professor of Medicine

Bahiana School of Medicine and Public Health



CD has been reimbursed by Sanofi-Aventis, Novartis, Merck Sharp Dohme, and Eli Lilly as an investigator of clinical trials.

Krishna M. Sundar, MD

Adjunct Assistant Professor

University of Utah


Pulmonary & Critical Care Research

IHC Urban South Intermountain Utah Valley Pulmonary Clinic




KMS declares that he has no competing interests.

  • Differentials

    • Central sleep apnoea and Cheyne-Stokes respiration (CSB)
    • Narcolepsy
    • Insufficient sleep
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  • Guidelines

    • Continuous positive airway pressure for the treatment of obstructive sleep apnoea/hypopnoea syndrome
    • Treatment of adult obstructive sleep apnea with positive airway pressure
    More Guidelines
  • Patient leaflets

    Sleep apnoea in adults (obstructive)

    More Patient leaflets
  • Calculators

    Epworth Sleepiness Scale (ESS)

    More Calculators
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