Autoadjusted versus fixed CPAP for obstructive sleep apnoea: a multicentre, randomised equivalence trial

Area of Science:

• Sleep Medicine
• Respiratory Medicine
• Clinical Trials

Background:

• Obstructive sleep apnoea syndrome (OSAS) is commonly treated with fixed-level continuous positive airway pressure (fCPAP).
• Automatic continuous positive airway pressure (autoCPAP) devices are increasingly utilized for home therapy.
• This study compares the long-term efficacy of autoCPAP versus fCPAP in managing OSAS symptoms.

Purpose of the Study:

• To determine if autoCPAP is equivalent to fCPAP in improving long-term sleepiness in patients with OSAS.
• To compare subjective and objective measures of sleepiness between autoCPAP and fCPAP treatments over two years.

Main Methods:

• A multicentre equivalence trial randomized 208 OSAS patients (median Epworth Sleepiness Score [ESS] 13, Apnoea/Hypopnoea Index 48.4/hour).
• Patients were assigned to autoCPAP (5-15 mbar) or fCPAP (pressure set at autoCPAP's 90th percentile during adaptation).
• Coprimary outcomes included changes in ESS and objective sleepiness (sleep resistance time) from baseline to 2 years, with predefined equivalence ranges.

Main Results:

• After 2 years, both autoCPAP and fCPAP groups showed similar reductions in sleepiness (mean ESS change: -6.3 vs. -6.2).
• Objective sleepiness also improved similarly, with increases in sleep resistance time (+8.3 min vs. +6.3 min).
• Equivalence was confirmed within the specified ranges for both ESS and sleep resistance time; blood pressure and costs were also comparable.

Conclusions:

• AutoCPAP and fCPAP demonstrate equivalent efficacy in improving subjective and objective sleepiness in OSAS patients over a 2-year period.
• The findings support autoCPAP as a viable alternative to fCPAP for long-term OSAS management.
• Treatment costs associated with both autoCPAP and fCPAP were found to be similar.