Could HRV be a Valuable Predictor for CPAP Adherence?

Study Overview
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Brief Summary
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This study aim to evaluate if the improvement of heart rate variability for the continuous positive airway pressure titration night can predict the short and long term continuous positive airway pressure adherence for patients with moderate to severe OSA.

Detailed Description
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Heart rate variability (HRV) represents autonomic regulation and had been used in varies situation, especially the associated with cardiovascular outcomes and psychological diseases. HRV was also well known associated with the severity of obstructive sleep apnea (OSA) and could be improved after adequate treatments for OSA. Continuous positive airway pressure (CPAP) is the first choice of treatment for OSA and had been proved to able to improve HRV in OSA patients. However, the CPAP adherence is always problematic. Many CPAP predictors had been well documented but the HRV is never evaluated to be a potential predictor of CPAP adherence. Therefore, this study will evaluate the changes of HRV for polysomnography (PSG) night, for CPAP titration night to see if the changes of HRV in the CPAP titration night could predict CPAP adherence for OSA patients in Taiwan.

Official Title
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If Heart Rate Variability Can Predict Continuous Positive Airway Pressure Acceptance and Compliance for Patients With Obstructive Sleep Apnea ?

Conditions
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OSA, Autonomic Dysfunction, PAP, Adherence, Patient

Intervention / Treatment
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* Device: continuous positive airway pressure


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: aged:20 75y/o PSG revealed moderate to severe OSA (apnea hypopnea index [AHI] ≧15/hour) had been completed CPAP titration test Exclusion Criteria: aged<20y/o or >75 y/o mild OSA, (AHI <15/hour), or no OSA (AHI<5/hour) unstable cardiopulmonary disease, psychological diseases, using sleep pills.

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| CPAP opponent<br>CPAP opponent: moderate to severe OSA patients who refused CPAP therapy after PSG study and CPAP titration test. | |
| CPAP acceptor<br>CPAP acceptor: moderate to severe OSA patients who accepted CPAP therapy after PSG study and CPAP titration test and had purchased a PAP at home for long term use. | Device: continuous positive airway pressure<br>* Could the changes of HRV between PSG night and CPAP titration night predict the CPAP adherence?<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| If changes in LF/HF ratio (Low frequency/High frequency ratio) could be a valuable predictor for CPAP acceptance in OSA patients? | Changes of LF/HF ratio between PSG study night and CPAP titration night will be measured and evaluated its association with CPAP acceptance of one month CPAP trial at home in moderate to severe OSA patients. | 1 month | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| If CPAP treatment could improve LF/HF ratio after 6 months of treatment in moderate to severe OSA patients? | After CPAP treatments 6 months, PSG examination will be followed-up again. The changes of LF/HF ratio between baseline PSG and 6-months PSG will be measured and be evaluated it's differences between different CPAP usage pattern (no any use in CPAP opponents, suboptimal use in CPAP acceptors and optimal use in CPAP acceptors ). | 6 months |