Abstract
Background: CPAP (continuous positive airway pressure) is the standard therapy for obstructive sleep apnea (OSA). While a lot of studies analysed adherence of CPAP therapy in general, only little is known on adherence dependent on apnea-hypopnea index (AHI), leakage and mask pressure.
Methods: In a retrospective data analysis we determined age-dependent adherence of 4821 German patients (age = 58.4±11.2 years; 17.6% female, 82.4% male) treated with the CPAP device S8 (ResMed, Sydney, Australia). We studied AHI, mean mask pressure, mean leakage, hours of use per night and efficiency (days of use/total days).
Results: Mean therapy duration was 3.5±3.6 years. In the subgroups AHI<5/h, AHI=5-10/h, AHI>10-15/h and AHI>15/h hours used/night (range 368 to 378 min) and days used/week (range 5.8 to 6.2) were similar. Furthermore, adherence was similar in the leakage subgroups <0.1 l/s, =0.1-0.2 l/s, >0.2-0.3 l/s, >0.3-0.4 l/s, >0.4-0.5 l/s and >0.5 l/s in terms of hours used/night (range 361 to 380 min) and days used/week (range 6.0 to 6.2). Up to mask pressure of 14 cmH2O hours used/night increased significantly. In the subgroup mask pressure=4-6 cmH2O patients used the device on average 350 min, whereas patients with mask pressure >12-14 cmH2O used it more than an hour longer (415min). Moreover, there was a continuous increase between the lowest mask pressure subgroup (4-6 cmH2O) and the highest mask pressure (>14 cmH2O). Range was 5.7 to 6.5 days used/week
Conclusion: Adherence to therapy is high and therapeutic efficacy is excellent in long-term CPAP users. Adherence increases with mask pressure.
- © 2011 ERS