engleski

The slope of the oxygen desaturation as a predictor of CPAP adherence in severe OSA patients

This study aims to investigate the relationship of oxygen desaturation and apnea severity expressed as apnea-hypopnea index (AHI) with CPAP adherence in severe OSA patients. A retrospective study was performed on 70 severe OSA patients, with Slope Index (SI) calculated as the averaged quotient of difference between the blood oxygen saturation level before and after the obstructive event (ΔSpO2) and the duration of the obstructive event throughout the night. CPAP usage for ≥4 hours/night on ≥70% of nights was defined as good CPAP adherence. Increased SI was associated with decreased percentage of nights with CPAP usage ≥4 hours during first three months of CPAP usage (r=-0.314 ; p=0.008), whereas not significantly during the first month of CPAP usage (r=-0.225 ; p=0.062) No significant correlation was observed between AHI and percentage of nights with CPAP usage ≥4 hours during initial therapy periods. The SI was significantly higher in patients with poor adherence during both observed periods of CPAP usage in comparison to patients with good adherence (p=0.011 and p=0.005, respectively). No difference in AHI was recognized between patients with good and poor adherence during both time spans of CPAP usage. When logistic regression analyses were performed, a lower SI was a predictor of good CPAP adherence during the first month and first three months of CPAP therapy (ß=0.018 ; p=0.039 ; R2=12.2% ; p=0.035 and ß=0.004 ; p=0.019 ; R2=16.6% ; p=0.010, respectively). Patients with a greater slope of the oxygen desaturation curve were recognized as less likely to have good CPAP adherence following therapy onset. This novel parameter might give an insight on the impact of desaturation severity on CPAP adherence and might be valuable in recognizing patients with severe OSA at risk for poor CPAP adherence.

CPAP adherence, oxygen desaturation, OSA

nije evidentirano