Trial Outcomes & Findings for Comparison of Breathing Event Detection by a Continuous Positive Airway Pressure Device to Clinical Polysomnography (NCT NCT00836758)
NCT ID: NCT00836758
Last Updated: 2019-01-16
Results Overview
Apnea-hypopnea index (AHI) is the combined average number of apneas and hypopneas that occur per hour of sleep. The Apnea index (AI) is the average number of apneas that occur per hour of sleep. The Hypopnea index (HI) is the average number of hypopneas that occur per hour of sleep. The PSGs were manually scored to determine the apnea-hypopnea index. This value was then compared to the PAP device which utilized the AED algorithm to determine the apnea-hypopnea index.
COMPLETED
NA
115 participants
one night
2019-01-16
Participant Flow
A total of 148 (PSGs and overnights with PAP therapy), collected from 115 unique participants, were included in this analysis.
119 studies had a technically adequate recording and were collected from 90 patients (29 patients participated in two studies). These 119 studies were pooled with another 29 studies from another trial for a total of 148 studies. 4 patients participated in both trials and 3 of these patients contributed two recordings.
Unit of analysis: Overnight PSG and AED algorithms
Participant milestones
| Measure |
All Participants
Data was collected from participants that participated in a multi-center, randomized, double-blind trial comparing three modes of positive pressure delivery who had overnight PSGs.
|
|---|---|
|
Overall Study
STARTED
|
115 148
|
|
Overall Study
COMPLETED
|
115 148
|
|
Overall Study
NOT COMPLETED
|
0 0
|
Reasons for withdrawal
Withdrawal data not reported
Baseline Characteristics
Comparison of Breathing Event Detection by a Continuous Positive Airway Pressure Device to Clinical Polysomnography
Baseline characteristics by cohort
| Measure |
CPAP Device
n=115 Participants
Breathing event detection (AED) by the continuous positive airway pressure (CPAP) device will be compared to breathing event detection by a simultaneous PSG (manual PSG scoring).
Analysis with AED and manual PSG scoring: The CPAP device will be set-up at a sub-therapeutic pressure and will remain at this pressure for the entire night, if tolerated. Then the events will be analyzed with Automatic Event Detection (AED) and manual PSG scoring.
|
|---|---|
|
Age, Continuous
|
49.5 years
STANDARD_DEVIATION 11.3 • n=5 Participants
|
|
Sex: Female, Male
Female
|
31 Participants
n=5 Participants
|
|
Sex: Female, Male
Male
|
84 Participants
n=5 Participants
|
|
Region of Enrollment
United States
|
115 participants
n=5 Participants
|
|
BMI
|
36.2 kg/m^2
STANDARD_DEVIATION 7.6 • n=5 Participants
|
PRIMARY outcome
Timeframe: one nightApnea-hypopnea index (AHI) is the combined average number of apneas and hypopneas that occur per hour of sleep. The Apnea index (AI) is the average number of apneas that occur per hour of sleep. The Hypopnea index (HI) is the average number of hypopneas that occur per hour of sleep. The PSGs were manually scored to determine the apnea-hypopnea index. This value was then compared to the PAP device which utilized the AED algorithm to determine the apnea-hypopnea index.
Outcome measures
| Measure |
Manual PSG Scoring
n=148 Overnight PSG and AED algorithms
The PSGs were manually scored with the aid of computer software by a PSG technologist at a central scoring facility. The technologist was blinded to the event signal during manual scoring (the event signal was not visible in the montages used for scoring). Sleep staging and respiratory events were scored using 2007 American Academy of Sleep Medicine (AASM) guidelines. The scoring of a hypopnea required that the event be associated with a ≥ 4% oxygen desaturation.
|
Automatic Event Detection
n=148 Overnight PSG and AED algorithms
The AED algorithm used the following criteria to identify respiratory events. An apnea was detected when there was an 80% or greater reduction in the airflow for 10 sec or longer in comparison with the average airflow over the previous 2 minutes. A hypopnea was detected when there was a device estimated 40% reduction in airflow for ≥ 10 sec but \< 60 sec compared with the average airflow over the previous 2 minutes. The hypopnea detection algorithm required the presence of two recovery breaths that nominally were at least 75% to 80% of the baseline airflow. The algorithm also looked for evidence of flow limitation to detect hypopneas. The algorithm monitored the flow signal for changes in peak flow, and the shape of the inspiratory airflow signal that would be associated with flow limited breathing.
|
|---|---|---|
|
Apnea-hypopnea Indices (AHI) as Determined by Polysomnography (PSG) vs Automatic Event Detection (AED ) Algorithm
Apnea index
|
2.4 events per hour
Standard Deviation 4.8
|
3.2 events per hour
Standard Deviation 5.25
|
|
Apnea-hypopnea Indices (AHI) as Determined by Polysomnography (PSG) vs Automatic Event Detection (AED ) Algorithm
Apnea-hypopnea index
|
5.6 events per hour
Standard Deviation 8.0
|
5.8 events per hour
Standard Deviation 6.3
|
|
Apnea-hypopnea Indices (AHI) as Determined by Polysomnography (PSG) vs Automatic Event Detection (AED ) Algorithm
Hypopnea index
|
3.2 events per hour
Standard Deviation 5.2
|
2.6 events per hour
Standard Deviation 2.3
|
SECONDARY outcome
Timeframe: one nightMethodological comparisons utilizing ICC for detection of AHI, apnea index (AI) and hypopnea index (HI) were caculated between the values obtained by PSG and the REMstar Auto with A-Flex device.
Outcome measures
| Measure |
Manual PSG Scoring
n=148 Overnight PSG and AED algorithms
The PSGs were manually scored with the aid of computer software by a PSG technologist at a central scoring facility. The technologist was blinded to the event signal during manual scoring (the event signal was not visible in the montages used for scoring). Sleep staging and respiratory events were scored using 2007 American Academy of Sleep Medicine (AASM) guidelines. The scoring of a hypopnea required that the event be associated with a ≥ 4% oxygen desaturation.
|
Automatic Event Detection
The AED algorithm used the following criteria to identify respiratory events. An apnea was detected when there was an 80% or greater reduction in the airflow for 10 sec or longer in comparison with the average airflow over the previous 2 minutes. A hypopnea was detected when there was a device estimated 40% reduction in airflow for ≥ 10 sec but \< 60 sec compared with the average airflow over the previous 2 minutes. The hypopnea detection algorithm required the presence of two recovery breaths that nominally were at least 75% to 80% of the baseline airflow. The algorithm also looked for evidence of flow limitation to detect hypopneas. The algorithm monitored the flow signal for changes in peak flow, and the shape of the inspiratory airflow signal that would be associated with flow limited breathing.
|
|---|---|---|
|
Methodological Comparisons of AHI, Apnea Index (AI) and Hypopnea Index (HI) as Determined by Intra-class Correlation (ICC)
Apnea-Hypopnea Index
|
0.789 coefficient
|
—
|
|
Methodological Comparisons of AHI, Apnea Index (AI) and Hypopnea Index (HI) as Determined by Intra-class Correlation (ICC)
Apnea Index
|
0.825 coefficient
|
—
|
|
Methodological Comparisons of AHI, Apnea Index (AI) and Hypopnea Index (HI) as Determined by Intra-class Correlation (ICC)
Hypopnea Index
|
0.350 coefficient
|
—
|
Adverse Events
CPAP Device
Serious adverse events
Adverse event data not reported
Other adverse events
Adverse event data not reported
Additional Information
Results disclosure agreements
- Principal investigator is a sponsor employee
- Publication restrictions are in place