AKT · Respiratory/Airways diseaselow yield

Obstructive sleep apnoea

Repetitive upper-airway collapse during sleep → intermittent hypoxia and sleep fragmentation

Overview

Repetitive collapse of the upper airway during sleep causing apnoeas/hypopnoeas, intermittent hypoxia and fragmented sleep. It presents with snoring, witnessed apnoeas and daytime sleepiness, typically in an overweight, middle-aged man. It is diagnosed by sleep study and treated with weight loss and CPAP. It is important because of road-traffic-accident risk (DVLA), hypertension and cardiovascular consequences.

Recognise

Loud snoring, witnessed apnoeas, choking/gasping arousals; daytime somnolence (Epworth Sleepiness Scale), morning headache, poor concentration
Risk factors: obesity, large neck circumference, male, middle age, retrognathia, alcohol/sedatives, hypothyroidism, acromegaly
Associations: hypertension (often resistant), atrial fibrillation, type 2 diabetes, cardiovascular disease, pulmonary hypertension

Red flags

Excessive sleepiness with driving/occupational risk → advise re driving and DVLA notification (group 1: stop until controlled)
Severe OSA with cardiovascular/respiratory consequences → prompt treatment

Differentials & how to tell them apart

Simple snoringno apnoeas/desaturations or daytime sleepiness on sleep study

Other causes of daytime sleepinessnarcolepsy, depression, poor sleep hygiene, sedatives, hypothyroidism

Obesity hypoventilation syndromedaytime hypercapnia in obesity (overlaps OSA)

Investigations

Epworth Sleepiness Scale; sleep study (polysomnography or home oximetry/respiratory polygraphy — apnoea-hypopnoea index grades severity); assess for secondary causes (TFTs, acromegaly); BP and cardiovascular/metabolic assessment.

Management

Weight loss + CPAP (moderate-severe); mandibular device for mild/CPAP-intolerant

1Assess sleepiness (Epworth) and confirm with a sleep study; treat reversible/secondary causes and start weight loss/lifestyle measures. Moderate-severe OSA → CPAP.Gate: Advise on driving and DVLA notification where sleepiness poses an accident risk (group 1: stop driving until satisfactorily controlled).
2Mandibular advancement device for mild OSA or CPAP intolerance; manage the associated hypertension/cardiovascular/metabolic risk.

Weight loss + lifestyle (reduce alcohol/sedatives, sleep position) + treat secondary causes — foundation; manage hypothyroidism/acromegaly

CPAP (continuous positive airway pressure) — first-line for moderate-severe OSA — splints the airway open; improves sleepiness, BP and accident risk

Mandibular advancement device — for mild OSA or CPAP intolerance

DVLA advice + manage cardiovascular risk — counsel on driving/occupational sleepiness; treat hypertension

Key points

Overweight middle-aged man + loud snoring + witnessed apnoeas + daytime sleepiness (Epworth) = OSA → sleep study, then weight loss + CPAP (moderate-severe). Drives resistant hypertension/AF/CV risk. Counsel DVLA/driving for sleepiness.

Monitor & prognosis

Symptoms/Epworth, CPAP adherence, BP/cardiovascular risk, weight.

CPAP markedly improves symptoms, BP and accident risk with good adherence.

Source: NICE NG202 (OSA)