Continuous positive airway pressure education on adherence in adults with obstructive sleep apnoea

Poor adherence to continuous positive airway pressure (CPAP) treatment in patients with obstructive sleep apnoea (OSA) limits its therapeutic effectiveness and has a major impact on clinical outcomes. Effective education programme is important to enhance CPAP use. However, existing education programmes are either manpower or resource demanding and may not be feasible in clinical practice. Moreover, the Self-Efficacy Measure for Sleep Apnoea (SEMSA) has been widely adopted for assessing adherence-related cognitions on CPAP therapy in OSA patients, but it was not available for Chinese. The aims of this thesis are: (i) to perform linguistic and psychometric evaluation of a Chinese version of SEMSA (SEMSA-C); (ii) to examine the efficacy of brief motivational enhancement education programme in addition to standard care versus standard care only on improving adherence to CPAP treatment in patients with OSA. The SEMSA-C was obtained after the standard forward-backward translation process. A randomised controlled trial was then conducted on newly diagnosed OSA patients. Patients in the control group received standard care (SC) comprising advice on the importance of CPAP therapy and its care while those in the intervention group received SC plus motivational enhancement education programme (ME). ME focused to enhance subjects’ knowledge, motivation and self-efficacy to use CPAP, comprising one 45-minute session on the day after CPAP titration and one 10-minute telephone follow-up shortly after commencing CPAP treatment. Epworth Sleepiness Scale (ESS), SEMSA-C, and quality of life were assessed. CPAP usage data were downloaded at the completion of this 3-month study. The primary outcome was the CPAP adherence. Furthermore, 21 patients were randomly sampled at baseline and completed the SEMSA-C at one week. 100 patients (Men : Women, 84 : 16) with OSA indicated for CPAP treatment were recruited, with an average age of 52±10 years, and apnoea hypopnoea index (AHI) of 36.2±22 events/hour. Factor analysis of SEMSA-C identified three factors: risk perception, outcome expectancies and treatment self-efficacy. Their corresponding internal consistency was high with Cronbach’s alpha >0.88, which were larger than all correlations between subscales (Range: 0.14 to 0.58). The correlations between items and their hypothesized subscale (Range: 0.58 to 0.85) were generally higher than the correlations between items and their competing subscales (Range: -0.10 to 0.58). One-week test-retest intra-class correlation ranged from 0.70 to 0.82. CPAP adherence was associated with outcome expectancies and treatment self-efficacy at 3-month assessment. Furthermore, SEMSA-C demonstrated an improvement in self-efficacy (standardised response mean = 0.33, p = .044) but no significant changes were observed in the other two factors, after CPAP use. The 100 patients were followed for 3 months. The interventional effects maintained during the 3-month study period. There were a better CPAP use [higher daily CPAP usage of 2 hours/day (Cohen d = 1.33, p < .001), four-fold the number of subjects using CPAP for ≥ 70% of days with ≥ 4 hours per day (p < 0.001)], and greater improvements in ESS by 2.2 (p = 0.001) and treatment self-efficacy by 0.2 (p = 0.012) in the intervention group, relative to the control group. The traditional Chinese SEMSA-C possesses satisfactory psychometric properties. It is a reliable and responsive instrument to measure perceived risks, outcome expectancies and treatment self-efficacy in Chinese patients with OSA. Moreover, the newly developed brief motivational enhancement education programme in addition to standard care is effective in improving adherence to CPAP treatment, treatment self-efficacy and daytime sleepiness.published_or_final_versionNursing StudiesDoctoralDoctor of Nursin