Six early CPAP-usage behavioural patterns determine peak CPAP adherence and permit tailored intervention, in patients with obstructive sleep apnoea

Background High rates of non-adherence to continuous positive airway pressure (CPAP) in obstructive sleep apnoea hamper good clinical outcomes. Current recommendations assumes two behaviours (adherence and non-adherence) and days 7-90 follow-up post-CPAP initiation mitigates against non-adherence. Objectives To investigate associations between early CPAP-usage behaviours and (1) CPAP adherence at month 3 of treatment and (2) sleep centres' treatment pathways (the procedures patients undergo that may affect barriers or facilitators of CPAP adherence). Methods We conducted growth mixture modelling (GMM) on retrospective data from 1000 patients at 5 UK sleep centres. Night 1 to month 3 telemonitored CPAP-usage data were downloaded from 200 patients per centre who started CPAP in 2019 (100) or 2020 (100). Adherence was defined using accepted criteria (mean CPAP-usage ≥4 hours/night for ≥70% of nights). Results GMM identified six distinct CPAP-usage behaviour patterns over month 1. In four (54% of patients), CPAP-usage increased or decreased, in two (remaining 46%), CPAP-usage/non-usage was consistent. 62% of the cohort were non-adherent by month 3, despite pathways following current recommendations. 98% of patients who were non-adherent by month 3 were already non-adherent by month 1. Regression analysis with a separate dataset demonstrated that early CPAP-usage behaviour explained 86% of the variance in CPAP non-adherence at month 3. Conclusions These data, supported by previous work, indicate that recommended day 30-90 follow-up is too late to prevent CPAP non-adherence. Determining CPAP-usage behavioural pattern in week 2 identifies risk of CPAP non-adherence at month 3 and permits the possibility of tailored interventions.