To assess the effectiveness of a stage-matched intervention on adherence to mandibular advancement appliance (MAA) in participants with obstructive sleep apnoea (OSA).

A randomised parallel-arm, Hospital-based, clinical trial was undertaken at the Royal London Dental Hospital, UK. Fifty-six participants (Adults ≥ 18 years) with newly diagnosed OSA were enrolled in the study and randomised to intervention care (IC) and standardized care (SC) groups. Participants in the SC group received routine care whilst participants in the IC group received the stage-matched intervention, developed using the behaviour change model, the health-action process approach (HAPA). Data indicating MAA adherence was collected both objectively and subjectively, from micro-sensors embedded in the MAA design and sleep diaries, respectively at 3- and 6-months. In addition, a range of questionnaires was designed to assess risk perception, outcome expectancy, self-efficacy (SEMSA), daytime sleepiness, quality of sleep, socioeconomic position, and social support.

The mean objective adherence for 30 participants at 3-month (IC = 15, SC = 15) was 2.02 (SD = 2.68) vs 2.63 (SD = 2.57) hours/night in the IC and SC group respectively. Whilst the mean objective adherence for 25 participants at 6-month (IC = 10, SC = 15) was 2.42 (SD = 2.59) vs 3.21 (SD = 3.37) hours/night for IC and SC groups respectively. No correlation was seen between daytime sleepiness (p = 0.24), quality of sleep (p = 0.96), social support (p = 0.52), socioeconomic position (p = 0.96) and mean adherence. Linear regression for adherence presented a positive coefficient for risk perception (p = 0.035, r² = 0.16) and outcome expectancy (p = 0.003, r² = 0.28).

Given the positive correlation between risk perception, outcome expectancy and patient adherence. Further research would be beneficial in describing the determinants of adherence, such as risk perception, and outcome expectancy in relation to adherence to MAA.