# Continuous Positive Airway Pressure Versus Nocturnal Oxygen in Obstructive Sleep Apnea: A Propensity Score Matching Study

## TL;DR

CPAP is more effective than oxygen therapy for long-term survival in obstructive sleep apnea patients.

## Contribution

A propensity score matching study shows CPAP improves five-year survival over oxygen therapy in OSA patients.

## Key findings

- CPAP-treated patients had significantly lower five-year mortality compared to those on oxygen therapy.
- CPAP provided better control of respiratory events, with a lower residual Apnea–Hypopnea Index.
- Propensity score matching confirmed the survival benefit of CPAP across different analytical approaches.

## Abstract

What are the main findings?
Continuous positive airway pressure (CPAP) was associated with significantly higher five-year survival compared with nocturnal oxygen therapy in patients with obstructive sleep apnea.CPAP achieved superior control of respiratory events, with a markedly lower residual Apnea–Hypopnea Index than oxygen therapy.

Continuous positive airway pressure (CPAP) was associated with significantly higher five-year survival compared with nocturnal oxygen therapy in patients with obstructive sleep apnea.

CPAP achieved superior control of respiratory events, with a markedly lower residual Apnea–Hypopnea Index than oxygen therapy.

What are the implications of the main findings?
CPAP should remain the preferred first-line therapy for obstructive sleep apnea due to its association with improved long-term survival.Nocturnal oxygen therapy may be considered for CPAP-intolerant patients but appears to provide less protection against mortality.

CPAP should remain the preferred first-line therapy for obstructive sleep apnea due to its association with improved long-term survival.

Nocturnal oxygen therapy may be considered for CPAP-intolerant patients but appears to provide less protection against mortality.

Background: Obstructive sleep apnea (OSA) affects quality of life and increases cardiovascular risk. Nocturnal oxygen therapy (NOT) offers a potential alternative for patients intolerant to CPAP. The objective of this study was to compare NOT and continuous positive airway pressure (CPAP) by evaluating five-year survival in patients with obstructive sleep apnea. Methods: A retrospective cohort study was conducted using propensity score matching (PSM) methodology. A PSM analysis was conducted to reduce selection bias due to differences in baseline characteristics between patients using CPAP and those receiving oxygen therapy. Balance between treated and untreated groups was assessed using standardized mean differences. A PSM was estimated using a logistic regression model, matching patients adherent to CPAP therapy to those treated with NOT. Results: A total of 497 patients with a confirmed diagnosis of OSA were included in the analysis. The mean age was 62.1 years (SD13.6), and 54.3% (270/497) were male. Overall, 42.1% (209/497) of the patients were over 65 years old. Of the total, 303 patients received CPAP therapy and 194 received NOT. After PSM, a matched cohort of 370 patients (185 per group) was obtained. The CPAP-treated group showed a significantly lower residual Apnea–Hypopnea Index compared to the oxygen therapy group (3.9, IQR: 1.8–6.5 vs. 15, IQR:7.5–29.1; p < 0.001), indicating better physiological control of respiratory events. Treatment with CPAP was associated with a significantly lower risk of mortality compared with NOT across analytical approaches, including weighted logistic regression (OR = 0.11; 95% CI 0.02–0.48; p = 0.004) and PSM with bootstrap estimation (ATT = −0.12; 95% CI −0.22 to −0.01; p = 0.030). Conclusions: In this cohort, higher five-year survival was observed among patients with OSA treated with CPAP compared with those receiving supplemental oxygen. These findings indicate a favorable association between CPAP use and long-term outcomes, supporting its role as the preferred first-line therapy in patients with OSA.