Relationship between Clinical and Polysomnography Measures Corrected for CPAP Use

Area of Science:

• Sleep Medicine
• Respiratory Medicine
• Patient-Reported Outcomes

Background:

• Obstructive sleep apnea (OSA) treatment effectiveness is often assessed using polysomnography (PSG) measures like the apnea-hypopnea index (AHI).
• Patient-reported outcomes (PROs) for OSA burden may not align with PSG findings, a discrepancy potentially linked to continuous positive airway pressure (CPAP) adherence.
• Understanding this discordance is vital for optimizing OSA management.

Purpose of the Study:

• To investigate the hypothesis that PROs correlate better with AHI when AHI is adjusted for mean nightly CPAP use.
• To determine if correcting PSG measures for CPAP adherence enhances their association with patient-reported OSA burden.

Main Methods:

• A cross-sectional study involving 459 adults undergoing CPAP therapy for OSA.
• Collected five PROs of OSA burden at baseline and after six months of CPAP treatment.
• Correlated changes in PROs with changes in AHI and CPAP-use-corrected AHI, alongside other PSG metrics.

Main Results:

• The change in AHI showed weak correlations with only two of five PROs.
• The change in mean nightly AHI, corrected for CPAP use, demonstrated statistically significant correlations with four out of five PROs.
• Similar improvements in correlation were observed for other PSG measures when corrected for CPAP use.

Conclusions:

• Adjusting polysomnography measures for CPAP use significantly improved correlations with patient-reported outcomes.
• This finding highlights the importance of considering CPAP adherence in the interpretation of OSA treatment efficacy.
• CPAP use correction offers a more refined assessment of OSA burden and treatment response.