Update on the assessment and investigation of adult obstructive sleep apnoea

Obstructive sleep apnoea (OSA) is common. Medicare Benefits Schedule rules regarding which patients are eligible for a sleep study without first needing to see a sleep or respiratory specialist have recently changed and incorporate validated questionnaires of OSA risk and subjective sleepiness.

The aim of this article is to bring general practitioners (GPs) up to date with the key factors that should be assessed when considering whether a patient has OSA. It also highlights the strengths and weaknesses of the screening questionnaires, and the pros and cons of different types of sleep studies.

OSA may significantly affect quality of life, mood, safety and cardiovascular risk. Assessment should focus on symptoms. Screening questionnaires have high sensitivity but, when used alone, poor specificity for moderate-to-severe OSA. The Epworth Sleepiness Scale (ESS) is a poor marker of OSA but does predict response to treatment when elevated. GPs can directly order sleep studies when OSA questionnaires are positive and the ESS is elevated; however, negative questionnaires do not exclude OSA or another sleep disorder.