Variability of breathing during wakefulness while using CPAP predicts adherence

Area of Science:

• Respiratory Medicine
• Sleep Science
• Physiological Monitoring

Background:

• Continuous positive airway pressure (CPAP) is the standard treatment for obstructive sleep apnoea (OSA).
• Long-term adherence to CPAP therapy remains a significant challenge, with approximately 50% of patients discontinuing treatment.
• Existing behavioral and educational interventions have limited success in improving CPAP adherence.

Purpose of the Study:

• To investigate whether breathing regularity during wakefulness can serve as a physiological predictor of CPAP adherence in OSA patients.
• To identify a specific threshold for breathing regularity that indicates a higher likelihood of poor CPAP adherence.

Main Methods:

• A prospective study enrolled 79 CPAP-naïve patients diagnosed with OSA.
• Respiratory inductance plethysmography was used to collect breathing signals while patients wore CPAP during wakefulness.
• Breathing regularity was quantified using the coefficient of variation (CV) of estimated tidal volume (V_T).

Main Results:

• Patients with poor CPAP adherence exhibited a significantly higher CV for estimated V_T compared to those with good adherence (44.2 vs 26.0, P < 0.001).
• A CV cut-off value of 34.0 for estimated V_T was identified as a predictor of poor adherence in the derivation group.
• This cut-off value demonstrated good predictive accuracy in the validation group (sensitivity 0.78, specificity 0.83).

Conclusions:

• Breathing regularity during wakefulness, while wearing CPAP, is an objective predictor of short-term CPAP adherence.
• This physiological measure can help identify OSA patients at risk for poor adherence at the initiation of therapy.
• This finding may lead to more targeted interventions for improving long-term CPAP use.