Automatic Derivation of Continuous Positive Airway Pressure Settings: Comparison with In-Laboratory Titration

This study was designed to investigate differences in the final recommended pressure setting between that derived from an autotitrating continuous positive airway pressure (APAP) device and manual in-laboratory continuous positive airway pressure (CPAP) titration, as well as the factors that influence pressure differences in patients with obstructive sleep apnea (OSA).

This study enrolled 50 patients with OSA. All patients underwent both APAP titration and manual CPAP titration. We obtained the average device pressure ≤90% of the time (APAP₉₀) from the downloaded manual for the APAP machine and the optimal pressure obtained by manual CPAP titration (CPAP_manual). We placed the subjects into three groups based on the pressure difference (ΔP) obtained by subtracting CPAP_manual from APAP₉₀: 1) Prequal (ΔP=0), 2) CPAP_manual+ (ΔP ≤-1), and 3) APAP₉₀+ (ΔP ≥1). Regression analysis was conducted to identify predictive factors associated with ΔP.

The values of APAP₉₀ and CPAP_manual were 9.50±3.03 cmH₂O and 9.48±2.71 cmH₂O (mean±SD), respectively (p=0.95). The Pr_equal, CPAP_manual+, and APAP₉₀+ groups comprised 9 (18%), 23 (46%), and 18 (36%) subjects, respectively. Regression analyses revealed that male sex [β=3.539, 95% confidence interval (CI)=0.040-7.039], body mass index (BMI) (β=0.186, 95% CI=0.020-0.352), and average usage per day (β=0.768, 95% CI=0.077-1.459) were associated with ΔP.

While the mean pressure in the overall cohort did not differ significantly between APAP₉₀ and CPAP_manual, there was a discordance majority showing different single pressures obtained when applying the two titration methods. Being Male, having an increased BMI, and having an increased average usage per day of APAP were significantly correlated with increased ΔP in this study.