Comparison of CPAP Modalities for OSA Treatment

A Crossover Study Comparing Fixed Continuous Airway Positive Pressure, FLEX- PLUS and Sensawake Modalities for OSA Treatment

This is a crossover study comparing the effect of CPAP Fixed Pressure, CPAP FLEX -PLUS and Sensawake on sleep quality, adherence to treatments, and PSG parameters in patients with moderate to severe OSA.

Obstructive sleep apnea (OSA) is associated with behavioral, cognitive, metabolic and cardiovascular conditions. Continuous Positive Airway Pressure (CPAP) is the gold standard treatment for OSA. Despite being the most effective treatment for OSA, 46 to 83% of patients do not adhere to CPAP. New technologies for CPAP treatment have been developed in order to improve patient's comfort, adherence and effectiveness in reducing apnea, hypopneas and flow limitation events. As an example, the FLEX- PLUS technology which increases inspiratory positive pressure and decreases expiratory positive pressure would soften the rhythm of breathing. Sensawake is another technology which evaluates breathing pattern changes during CPAP therapy. When the breathing pattern suggests that patient is awake, a prompt relief in pressure is activated, like ramp feature. However, it is not clear whether CPAP FLEX- PLUS or Sensawake are superior compared with fixed pressure CPAP, in terms of polysomnographic parameters, especially flow limitation or adherence to treatment. Objective: To compare the effect of fixed pressure CPAP, CPAP FLEX- PLUS and Sensawake on sleep and compliance parameters in patients with moderate to severe OSA. Methods: Fifty male patients with moderate to severe OSA will be included in a crossover design study. All patients will use each CPAP modality for 30 days in a randomized order, namely CPAP with Fixed Pressure, Flex- PLUS and Sensawake. A week of washout period will be applied between treatments. All patients will wear the same nasal mask brand. At the end of each treatment (every 4 weeks), patients will undergo polysomnography and fill out Epworth, FOSQ, Pittsburgh questionnaires and a visual analogue scale assessing CPAP side effects and patient´s comfort. Finally, adherence to CPAP modalities will be systematically checked.

This is a crossover study comparing different CPAP modalities in a group of patients with moderate to severe OSA.

Participants have never had contact with CPAP, therefore were not aware of PAP modality prescribed. Investigator were also naive, as well as sleep specialist responsible for Polysomnography reports. Only respiratory therapist who was assigned to CPAP clinic was aware of patient´s treatment condition.

Four consecutive weeks with CPAP C- FLEX PLUS treatment. After these 4 weeks, patients will undergo full PSG with CPAP FLEX- PLUS. Patients will also fill out Epworth Sleepiness Scale, Pittsburgh Sleep Quality Index, Functional Outcome Sleep Questionnaire, and visual analogue scale assessing CPAP side effects and patient´s comfort. Adherence to 4-week treatment will be checked. Treatment is followed by 7-day washout period.

Four consecutive weeks with CPAP Sensawake treatment. After these 4 weeks, patients will undergo full PSG with the same CPAP modality. Patients will also fill out Epworth Sleepiness Scale, Pittsburgh Sleep Quality Index, Functional Outcome Sleep Questionnaire, and visual analogue scale assessing CPAP side effects and patient´s comfort. Adherence to 4-week treatment will be checked. Treatment is followed by 7-day washout period.

Four consecutive weeks with CPAP fixed pressure treatment. After these 4 weeks, patients will undergo full PSG with the same CPAP modality. Patients will also fill out Epworth Sleepiness Scale, Pittsburgh Sleep Quality Index, Functional Outcome Sleep Questionnaire, and visual analogue scale assessing CPAP side effects and patient´s comfort. Adherence to 4-week treatment will be checked. Treatment is followed by 7-day washout period.

Continuous positive airway pressure (CPAP) is the gold standard treatment for moderate and severe OSA, and it has been known to apply positive pressure in the upper airways, acting as a pneumatic splint preventing the upper airway collapse during sleep. CPAP C- Flex Plus by Philips - Respironics works just as CPAP Fixed Pressure, but increases the pressure delivered in the begining of inhalation to softens the breathing rhythm of the CPAP user. CPAP with SensAwake by Fisher and Paykel works just as CPAP fixed pressure but when the breathing pattern suggests that patient is awake, a prompt relief in pressure to the lowest most comfortable level is activated, like ramp feature.

Flow limitation in percentage of total sleep time. The flow limitation will be assessed by the flow curve obtained in the polysomnographic recording.

Inclusion Criteria: male gender apnea-hypopnea index (AHI) score of ≥20 events/hour of sleep 30-65 years-old body mass index (BMI) ≤40 Kg/m² Exclusion Criteria: major neurological, psychiatric, cardiac or respiratory disease use of psychoactive medication other sleep disorders patients referred to PSG for Bilevel, considered the need for PAP ≥ 18 cm H2O Previous contact with any OSA treatment.