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ukmla 2026

Obstructive Sleep Apnoea (ENT perspective)

Repeated upper airway collapse during sleep — apnoeas/hypopnoeas, sleep fragmentation, excessive daytime sleepiness. CPAP first-line for moderate-severe (NICE NG202). ENT: assess anatomical contributors

Review date
reviewed 2026-04-05
Reading time
6 min read
Author
Dr Kola Tytler MBBS CertHE MBA MSt MRCGP
ENTcommonchronic
On this page
Condition details
ENT
common
6 min read
reviewed 2026-04-05
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About This Page

This is a clinician-written, evidence-based summary aligned to the 2026 MLA Content Map. It is intended for medical students and junior doctors preparing for the UKMLA. Always cross-reference with NICE guidance, local protocols, and clinical judgement.

Key points

  • Recurrent upper airway obstruction during sleep → apnoeas (≥10 sec) and hypopnoeas → desaturation + sleep fragmentation
  • Symptoms: excessive daytime sleepiness, loud snoring, witnessed apnoeas, unrefreshing sleep
  • Screening: Epworth ≥11 suggests excessive sleepiness. STOP-BANG questionnaire
  • Diagnosis: sleep study — AHI: mild 5–14, moderate 15–29, severe ≥30
  • NICE NG202: CPAP first-line for moderate-severe OSAHS. MAD for mild-moderate or CPAP intolerance
  • Children: adenotonsillectomy is first-line and often curative
  • DVLA: must inform if excessive sleepiness. Cannot drive until treated

Overview

OSAHS involves repeated partial (hypopnoea) or complete (apnoea) upper airway obstruction during sleep, causing oxygen desaturation and sleep fragmentation. Upper airway collapses from reduced pharyngeal muscle tone compounded by anatomical narrowing (obesity, tonsillar hypertrophy, retrognathia). From an ENT perspective, assessment for correctable anatomical factors is important — particularly tonsillar hypertrophy in children (most common cause) and in adults not tolerating CPAP.

Epidemiology

Affects ~4% middle-aged men, ~2% women. ~80% moderate-severe undiagnosed. Prevalence increases with age and BMI. Strongest risk factor: obesity. Others: male, >40, alcohol, sedatives, hypothyroidism, Down syndrome. In children: adenotonsillar hypertrophy is the most common cause.

Clinical Features

Symptoms
Excessive daytime sleepiness — falling asleep in meetings, driving
Loud snoring, witnessed apnoeas (partner reports)
Unrefreshing sleep, morning headache
Nocturia, reduced libido
Falling asleep while driving
Children: snoring, mouth breathing, behavioural problems, enuresis
Signs
Obesity (BMI >30), collar >17 inches
Crowded oropharynx: Mallampati III/IV, large tonsils, macroglossia
Retrognathia
Hypertension (OSA is most common secondary cause)
Children: adenotonsillar hypertrophy, adenoid facies

Investigations

First-line
Epworth Sleepiness Scale0–24 score. ≥11 = excessive sleepiness. Screening only
STOP-BANGSnoring, Tiredness, Observed apnoeas, Pressure, BMI >35, Age >50, Neck >40 cm, Gender male. ≥3 = high risk
Second-line
Home respiratory polygraphyRecords airflow, effort, SpO₂ overnight. Calculates AHI. Sufficient for most
Polysomnography (PSG)Gold-standard full sleep study — if diagnostic uncertainty or comorbid sleep disorders
Specialist
DISEDrug-induced sleep endoscopy — identifies level of collapse for surgical planning
TFTsExclude hypothyroidism as contributing factor

Management

NICE NG202 (OSAHS), 2021
1
Lifestyle (all patients)
  • Weight loss: 10% can significantly reduce AHI
  • Avoid evening alcohol and sedatives
  • Smoking cessation, exercise
  • Positional therapy if supine-predominant
2
CPAP (first-line moderate-severe)
  • Pneumatic splint keeping upper airway open
  • Offer for AHI ≥15 (moderate-severe)
  • For mild (AHI 5–14): offer if symptoms affect QoL or priority factors (e.g. professional driver)
  • Telemonitoring to support adherence
  • Minimum effective use ≥4 hours/night
3
MAD
  • Custom mandibular advancement device — holds mandible forward
  • Alternative for mild-moderate or CPAP intolerance
  • Less effective than CPAP for severe
4
ENT/surgical
  • Children: adenotonsillectomy = first-line, often curative
  • Adults: tonsillectomy if hypertrophy, nasal surgery to improve CPAP tolerance
  • DISE-guided multilevel surgery for selected CPAP failures
  • Hypoglossal nerve stimulation (Inspire) for selected patients
5
DVLA
  • MUST inform DVLA if excessive daytime sleepiness
  • Cannot drive until treated and symptoms controlled
  • Group 2 (HGV/bus): stricter — specialist assessment + CPAP compliance

Complications

  • Cardiovascular: Hypertension (most common secondary cause), AF, stroke, HF, MI
  • RTAs: 2–7× increased risk — DVLA notification mandatory
  • Metabolic syndrome, T2DM
  • Neurocognitive: Impaired concentration, depression
  • Pulmonary hypertension/cor pulmonale
  • Increased perioperative risk
UKMLA Exam Tips
  • 1AHI: mild 5–14, moderate 15–29, severe ≥30 — know for treatment decisions
  • 2CPAP first-line for moderate-severe (NICE NG202). MAD for mild-moderate/CPAP intolerance
  • 3In children: adenotonsillectomy FIRST-LINE — different from adults
  • 4DVLA: MUST notify if sleepy. Cannot drive until treated. Group 2 even stricter
  • 5OSA = most common SECONDARY cause of hypertension — consider in resistant HTN
  • 6Epworth ≥11 = excessive sleepiness but does NOT diagnose OSA — need sleep study
  • 7Mallampati IV (hard palate only visible) = most crowded oropharynx = highest OSA risk

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Verified Sources & References

NICE NG202 — OSAHS
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