Authors (including presenting author) :
CK Tseng, TF Chan, WK Tang, HW Ho, YF Cheng, CT Kwok, SO Ling, P Tam, CW Yim, PK Ng, YW Mok, HY Kwan
Affiliation :
Department of Respiratory Medicine, Kowloon Hospital
Keyword 1: :
Obstructive sleep apnoea syndrome
Keyword 2: :
oral appliances
Keyword 3: :
Clinical outcomes
Introduction :
Obstructive sleep apnoea syndrome (OSAS) is a common disorder that requires long-term effective treatment to prevent metabolic and cardiovascular risks. Continuous positive airway pressure(CPAP) remains the gold standard treatment but compliance is often poor. Literature suggested that oral appliance (OA) is an effective alternative with better compliance. Local data is scarce.
Objectives :
To determine the response rates and compliance of OA in OSAS patients.
Methodology :
This is a retrospective cohort study of OSA patients who underwent follow-up polysomnography (PSG) with their customized OA in the Department of Respiratory Medicine, Kowloon Hospital. They either failed to tolerate or refused CPAP. Their baseline Apnoea-Hypopnoea Index (AHI), Epworth Sleepiness Score(ESS), Body-Mass Index(BMI) and neck circumference were recorded. OA responders were divided into complete (AHI < 5/h), near-complete (AHI reduced to < 10/h and >50% reduction in baseline AHI) and partial (>50% reduction in baseline AHI). Otherwise they were non-responder. Compliance to OA was also evaluated.
Result & Outcome :
From 01/01/2016 to 07/08/2025, 157 patients had follow-up PSG with OA performed. Majority were male (n=101, 64.3%). Mean (SD) age was 59.6(10.6); AHI 23.0 (16.8); ESS 11.0(4.7); BMI 25.7(3.6); Neck circumference 37.9cm (4.4). At baseline, 41.4%, 31.2% and 27.4% had mild, moderate and severe OSA, respectively. About 36.9%(n=58) were responders, comprising 7.0% partial responders, 10.2% near complete responders, and 19.7% complete responders. Unlike reported in other literatures, OA response rates in our cohort were higher in moderate (n=24, 49.0%) and severe 3(n=19, 44.2%) OSA than in mild cases (n=15, 23.1%) (p=0.004). Although over half of them did not respond to OA (n=99, 63.1%), higher compliance rate to OA was noted among responders 82.7% than non-responders (38.4%). Conclusion: OA therapy demonstrated meaningful efficacy in patients with moderate and severe OSAS, with nearly one fifth achieving complete response and a further proportion showing near complete or partial improvement. Importantly, compliance was substantially higher among responders, underscoring the clinical value of OA as a practical alternative for patients unable to tolerate CPAP. Although overall response rates were modest, the stratified outcomes highlight that disease severity influences treatment success, suggesting that careful patient selection can optimize therapeutic benefit. These findings reinforce the role of OA in broadening management options for OSAS, particularly in real world settings where CPAP compliance remains challenging. Early identification of suitable candidates and structured follow up may enhance outcomes, reduce long term morbidity, and improve patients’ quality of life.
