Titration with automatic continuous positive airway pressure in obstructive sleep apnea

Autotitrating positive airway pressure (APAP) is an accepted titration method to determine the optimal positive airway pressure (PAP), for the treatment of obstructive sleep apnea (OSA). The required duration of APAP monitoring to determine a fixed continuous positive airway pressure level still remains to be established. We aimed to evaluate the variation in PAP level, delivered by APAP devices, at different periods of treatment, to determine the APAP treatment duration required to reach an effective and stable PAP level.

A cross-sectional study of 62 patients newly diagnosed with OSA were evaluated after 3 months of APAP therapy. APAP data corresponding to the first day (D1), first week (W1), seventh week (W7) and twelfth week (W12) under APAP therapy was collected. For the analysis of the pressure behaviour, the difference of P95th pressure level between W12 and W7 (P W12-W7), W12 and W1 (P W12-W1) and W12 and D1 (P W12-D1) was calculated.

There was a high correlation in P95th pressure level between D1 and W12 (r=0.771; p>0.0001), W1 and W12 (r=0.817; p>0.0001), and W7 and W12 (r=0.926; p>0.0001). This correlation progressively increased with APAP use. A significance difference was found in concordance between P W12-W7 and P W12-D1 (p=0.046) within the pressure range ±2cmH₂O. However there was no significant difference in concordance between P W12-W7 and P W12-W1.

One week of APAP therapy seems sufficient to determine an effective and stable PAP level, within the pressure range ±2cmH₂O.