Detecting Sleep Apnoea Syndrome in Primary Care with Screening Questionnaires and the Epworth Sleepiness Scale

Objective: To examine the utility of apnoea screening questionnaires, alone and in combination with the Epworth sleepiness scale (ESS), for detecting obstructive sleep apnoea (OSA) in primary care.

Design, Setting: Prospective validation study in an Australian general population cohort.

Participants: 424 of 772 randomly invited Tasmanian Longitudinal Health Study, 6th decade follow-up participants with OSA symptoms (mean age, 52.9 years; SD, 0.9 year) who completed OSA screening questionnaires and underwent type 4 sleep studies.

Main Outcome Measures: Clinically relevant OSA, defined as moderate to severe OSA (15 or more oxygen desaturation events/hour), or mild OSA (5-14 events/hour) and excessive daytime sleepiness (ESS ≥ 8); diagnostic test properties of the Berlin (BQ), STOP-Bang and OSA-50 questionnaires, alone or combined with an ESS ≥ 8.

Results: STOP-Bang and OSA-50 correctly identified most participants with clinically relevant OSA (sensitivity, 81% and 86% respectively), but with poor specificity (36% and 21% respectively); the specificity (59%) and sensitivity of the BQ (65%) were both low. When combined with the criterion ESS ≥ 8, the specificity of each questionnaire was high (94-96%), but sensitivity was low (36-51%). Sensitivity and specificity could be adjusted according to specific needs by varying the STOP-Bang cut-off score when combined with the ESS ≥ 8 criterion.

Conclusions: For people likely to trigger OSA assessment in primary care, the STOP-Bang, BQ, and OSA-50 questionnaires, combined with the ESS, can be used to rule in, but not to rule out clinically relevant OSA. Combined use of the STOP-Bang with different cut-off scores and the ESS facilitates a flexible balance between sensitivity and specificity.