Continuous positive airway pressure (CPAP) therapy remains the first-line treatment for moderate to severe obstructive sleep apnoea (OSA). When used consistently, CPAP effectively reduces apnoea–hypopnoea index (AHI), improves daytime somnolence, and mitigates cardiometabolic risk.
However, long-term therapeutic success is highly dependent on adherence.
Despite advances in mask design, humidification, and auto-adjusting technologies, adherence remains variable. Understanding the determinants of CPAP use and implementing structured follow-up is critical to improving patient outcomes.
Why Adherence Is Clinically Significant
OSA is associated with:
- Systemic hypertension
- Coronary artery disease
- Stroke
- Atrial fibrillation
- Insulin resistance
- Impaired neurocognitive performance
The Sleep Apnea Cardiovascular Endpoints (SAVE) trial demonstrated that cardiovascular benefit is most evident in patients who are adherent to CPAP therapy (McEvoy et al., 2016). Suboptimal use reduces potential risk modification.
From a primary care perspective, CPAP should be viewed as a long-term cardiometabolic intervention rather than solely a symptomatic treatment.
Determinants of CPAP Adherence
1. Early Usage Patterns
Adherence patterns are typically established within the first one to two weeks of therapy. Patients who experience early mask discomfort, pressure intolerance, or claustrophobia are at significantly higher risk of discontinuation.
Weaver and Grunstein (2008) highlight that proactive early intervention — including troubleshooting and behavioural support — strongly predicts long-term compliance.
Clinical implication: Early structured follow-up improves sustained use.
2. Mask Interface and Comfort
Mask discomfort remains one of the most common reasons for treatment cessation. Individualised mask selection based on facial anatomy, nasal patency, and breathing patterns improves tolerance.
Access to:
- Mask refitting
- Leak optimisation
- Humidification adjustment
- Pressure re-evaluation
can significantly reduce early drop-off rates.
3. Patient Education and Expectation Setting
Clear education regarding:
- OSA pathophysiology
- Long-term cardiovascular risk
- The importance of nightly consistency
- Realistic timelines for symptomatic improvement
enhances patient engagement.
The American Academy of Sleep Medicine (AASM) emphasises behavioural and educational interventions as part of comprehensive OSA management (Patil et al., 2019).
The Role of Ongoing Monitoring
Modern CPAP devices provide objective adherence and efficacy data. Regular review of:
- Usage hours
- Residual AHI
- Leak parameters
allows early identification of treatment barriers.
Collaborative care between sleep physicians, GPs, and CPAP providers ensures therapy remains optimised rather than static. CPAP therapy is highly effective when used consistently. Optimising adherence requires early follow-up, individualised equipment fitting, structured education, and ongoing monitoring.
Improving adherence is not merely a comfort issue. It is central to reducing long-term cardiovascular and metabolic morbidity associated with untreated OSA.