Trial Outcomes & Findings for Obstructive Sleep Apnea in World Trade Center Responders (NCT NCT01753999)
NCT ID: NCT01753999
Last Updated: 2025-04-30
Results Overview
The use (number of hours per night) will be compared between standard CPAP and CPAP flex. Results are based on the first treatment period only (pre-crossover).
COMPLETED
NA
317 participants
5 weeks after initiation of treatment
2025-04-30
Participant Flow
Subjects were recruited between January 2013 and December 2016 at three World Trade Center Health Program Clinical Centers of Excellence (Rutgers University, Icahn School of Medicine at Mount Sinai, and New York University School of Medicine).
Subjects without OSA were excluded from the trial.
Participant milestones
| Measure |
Standard CPAP Followed by CPAP-Flex
Participants were first treated with standard CPAP (continuous positive airway pressure with constant pressure) using a REMstar Auto A-flex in standard CPAP therapy mode for 4 weeks. The therapy mode was then switched to CPAP-Flex for 4 weeks. CPAP-Flex provides a decrease in pressure during expiration.
|
CPAP-Flex Followed by Standard CPAP
Participants were treated with CPAP-Flex (continuous positive airway pressure with a decrease in pressure during expiration) using a REMstar Auto A-flex in C-Flex mode for 4 weeks. The therapy mode was then switched to standard CPAP for 4 weeks. Standard CPAP provides a constant pressure (no decrease after expiration).
|
|---|---|---|
|
Period 1 - Initial Assignment
STARTED
|
155
|
162
|
|
Period 1 - Initial Assignment
Received Intervention
|
144
|
146
|
|
Period 1 - Initial Assignment
COMPLETED
|
116
|
112
|
|
Period 1 - Initial Assignment
NOT COMPLETED
|
39
|
50
|
|
Period 2 -Cross to Alternate Arm
STARTED
|
116
|
112
|
|
Period 2 -Cross to Alternate Arm
Received Intervention
|
103
|
95
|
|
Period 2 -Cross to Alternate Arm
COMPLETED
|
99
|
89
|
|
Period 2 -Cross to Alternate Arm
NOT COMPLETED
|
17
|
23
|
Reasons for withdrawal
| Measure |
Standard CPAP Followed by CPAP-Flex
Participants were first treated with standard CPAP (continuous positive airway pressure with constant pressure) using a REMstar Auto A-flex in standard CPAP therapy mode for 4 weeks. The therapy mode was then switched to CPAP-Flex for 4 weeks. CPAP-Flex provides a decrease in pressure during expiration.
|
CPAP-Flex Followed by Standard CPAP
Participants were treated with CPAP-Flex (continuous positive airway pressure with a decrease in pressure during expiration) using a REMstar Auto A-flex in C-Flex mode for 4 weeks. The therapy mode was then switched to standard CPAP for 4 weeks. Standard CPAP provides a constant pressure (no decrease after expiration).
|
|---|---|---|
|
Period 1 - Initial Assignment
Physician Decision
|
2
|
3
|
|
Period 1 - Initial Assignment
Withdrawal by Subject
|
19
|
20
|
|
Period 1 - Initial Assignment
Lost to Follow-up
|
18
|
27
|
|
Period 2 -Cross to Alternate Arm
Lost to Follow-up
|
13
|
17
|
|
Period 2 -Cross to Alternate Arm
Withdrawal by Subject
|
3
|
5
|
|
Period 2 -Cross to Alternate Arm
Physician Decision
|
1
|
1
|
Baseline Characteristics
TNR measurement was missing for 16 subjects at baseline.
Baseline characteristics by cohort
| Measure |
All Study Participants
n=317 Participants
Participants who were randomized to receive either standard CPAP or CPAP-Flex.
|
|---|---|
|
Age, Categorical
<=18 years
|
0 Participants
n=317 Participants
|
|
Age, Categorical
Between 18 and 65 years
|
288 Participants
n=317 Participants
|
|
Age, Categorical
>=65 years
|
29 Participants
n=317 Participants
|
|
Age, Continuous
|
53.29 years
STANDARD_DEVIATION 8.23 • n=317 Participants
|
|
Sex: Female, Male
Female
|
35 Participants
n=317 Participants
|
|
Sex: Female, Male
Male
|
282 Participants
n=317 Participants
|
|
Ethnicity (NIH/OMB)
Hispanic or Latino
|
45 Participants
n=317 Participants
|
|
Ethnicity (NIH/OMB)
Not Hispanic or Latino
|
264 Participants
n=317 Participants
|
|
Ethnicity (NIH/OMB)
Unknown or Not Reported
|
8 Participants
n=317 Participants
|
|
Race (NIH/OMB)
American Indian or Alaska Native
|
0 Participants
n=317 Participants
|
|
Race (NIH/OMB)
Asian
|
12 Participants
n=317 Participants
|
|
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
|
0 Participants
n=317 Participants
|
|
Race (NIH/OMB)
Black or African American
|
32 Participants
n=317 Participants
|
|
Race (NIH/OMB)
White
|
227 Participants
n=317 Participants
|
|
Race (NIH/OMB)
More than one race
|
33 Participants
n=317 Participants
|
|
Race (NIH/OMB)
Unknown or Not Reported
|
13 Participants
n=317 Participants
|
|
Apnea and Hypopnea Index (AHI4%)
|
17.01 Events/hour
STANDARD_DEVIATION 14.42 • n=317 Participants
|
|
Total Nasal Resistance
High Nasal Resistance (LogTNR>0.8)
|
132 Participants
n=301 Participants • TNR measurement was missing for 16 subjects at baseline.
|
|
Total Nasal Resistance
Low Nasal Resistance (LogTNR<=0.8)
|
169 Participants
n=301 Participants • TNR measurement was missing for 16 subjects at baseline.
|
PRIMARY outcome
Timeframe: 5 weeks after initiation of treatmentPopulation: Subjects who received the allocated treatment (i.e., turned on the PAP device). The difference between the number allocated and the number of analyzed is the result of some subjects (n=11 in CPAP and n=16 in C-Flex) who did not turn on the device despite taking it home. These were assumed to have NOT received the allocated treatment.
The use (number of hours per night) will be compared between standard CPAP and CPAP flex. Results are based on the first treatment period only (pre-crossover).
Outcome measures
| Measure |
Standard CPAP
n=144 Participants
Use of a standard CPAP (continuous positive airway pressure) device with constant pressure for 4 weeks to improve breathing during sleep
Standard CPAP: Use of the REMstar Auto A-Flex in standard CPAP therapy mode
|
CPAP-Flex
n=146 Participants
Use of CPAP-Flex (continuous positive airway pressure) device with decreased pressure during expiration for 4 weeks to improve breathing during sleep
CPAP - Flex: Use of Philips Respironics REMstar Auto A-Flex in C-Flex mode
|
|---|---|---|
|
Adherence to CPAP Pre-crossover
|
1 Hours/night
Interval 0.0 to 3.32
|
0.89 Hours/night
Interval 0.0 to 3.17
|
PRIMARY outcome
Timeframe: 9 weeks after initiation of treatmentPopulation: Subjects who received the allocated treatment (i.e., turned on the PAP device) in either the first treatment period or the second treatment period.
The use (number of hours per night) will be compared between standard CPAP and CPAP flex. Results are based on both periods.
Outcome measures
| Measure |
Standard CPAP
n=239 Participants
Use of a standard CPAP (continuous positive airway pressure) device with constant pressure for 4 weeks to improve breathing during sleep
Standard CPAP: Use of the REMstar Auto A-Flex in standard CPAP therapy mode
|
CPAP-Flex
n=249 Participants
Use of CPAP-Flex (continuous positive airway pressure) device with decreased pressure during expiration for 4 weeks to improve breathing during sleep
CPAP - Flex: Use of Philips Respironics REMstar Auto A-Flex in C-Flex mode
|
|---|---|---|
|
Adherence to CPAP Overall Study
|
1.03 Hours/night
Interval 0.0 to 3.33
|
0.8 Hours/night
Interval 0.0 to 2.86
|
SECONDARY outcome
Timeframe: 5 weeks after initiation of treatmentPopulation: Subjects who received treatment (turned on the PAP device). An additional 48 subjects on CPAP and 53 on CPAP-FLex were not analyzed as an AHI could not be generated during the analysis period due to insufficient use.
Efficacy will be evaluated by measuring the residual apnea and hypopnea index (AHI) while on treatment. The efficacy of standard CPAP and CPAP-flex will be compared. Results are based on the first treatment period only (pre-crossover).
Outcome measures
| Measure |
Standard CPAP
n=96 Participants
Use of a standard CPAP (continuous positive airway pressure) device with constant pressure for 4 weeks to improve breathing during sleep
Standard CPAP: Use of the REMstar Auto A-Flex in standard CPAP therapy mode
|
CPAP-Flex
n=93 Participants
Use of CPAP-Flex (continuous positive airway pressure) device with decreased pressure during expiration for 4 weeks to improve breathing during sleep
CPAP - Flex: Use of Philips Respironics REMstar Auto A-Flex in C-Flex mode
|
|---|---|---|
|
CPAP Efficacy
|
2.89 Events/hour
Standard Deviation 3.06
|
3.12 Events/hour
Standard Deviation 2.95
|
SECONDARY outcome
Timeframe: 9 weeks after initiation of treatmentPopulation: Subjects who received the allocated treatment (i.e., turned on the PAP device; N=239 for CPAP and N=249 for CPAP Flex). An additional 82 subjects on CPAP and 102 subjects on CPAP-Flex were not analyzed as an AHI could not be generated during the analysis period due to insufficient use.
Efficacy will be evaluated by measuring the residual apnea and hypopnea index (AHI) while on treatment. The efficacy of standard CPAP and CPAP-flex will be compared. Results are based on both treatment periods.
Outcome measures
| Measure |
Standard CPAP
n=157 Participants
Use of a standard CPAP (continuous positive airway pressure) device with constant pressure for 4 weeks to improve breathing during sleep
Standard CPAP: Use of the REMstar Auto A-Flex in standard CPAP therapy mode
|
CPAP-Flex
n=147 Participants
Use of CPAP-Flex (continuous positive airway pressure) device with decreased pressure during expiration for 4 weeks to improve breathing during sleep
CPAP - Flex: Use of Philips Respironics REMstar Auto A-Flex in C-Flex mode
|
|---|---|---|
|
CPAP Efficacy
|
2.71 events/hour
Standard Deviation 2.76
|
2.94 events/hour
Standard Deviation 2.65
|
OTHER_PRE_SPECIFIED outcome
Timeframe: 9 weeks after initiation of treatmentPopulation: Subjects with high total nasal resistance who received the allocated treatment (i.e., turned on the PAP device) in either the first treatment period or in the second treatment period.Total nasal resistance data are missing for 8 subjects.
The use (number of hours per night) will be compared between standard CPAP and CPAP flex for subjects with high total nasal resistance (logTNR\>0.8). The analysis is based on both periods.
Outcome measures
| Measure |
Standard CPAP
n=105 Participants
Use of a standard CPAP (continuous positive airway pressure) device with constant pressure for 4 weeks to improve breathing during sleep
Standard CPAP: Use of the REMstar Auto A-Flex in standard CPAP therapy mode
|
CPAP-Flex
n=110 Participants
Use of CPAP-Flex (continuous positive airway pressure) device with decreased pressure during expiration for 4 weeks to improve breathing during sleep
CPAP - Flex: Use of Philips Respironics REMstar Auto A-Flex in C-Flex mode
|
|---|---|---|
|
Adherence to CPAP Overall Study, Subjects With High Nasal Resistance
|
2.08 Hours/night
Interval 1.6 to 2.55
|
1.75 Hours/night
Interval 1.31 to 2.2
|
OTHER_PRE_SPECIFIED outcome
Timeframe: 9 weeks after initiation of treatmentPopulation: Subjects with low total nasal resistance who received the allocated treatment (i.e., turned on the PAP device) in either the first treatment period or in the second treatment period. Total nasal resistance data are missing for 8 subjects.
The use (number of hours per night) will be compared between standard CPAP and CPAP flex for subjects with low total nasal resistance (logTNR\<=0.8). The analysis is based on both periods.
Outcome measures
| Measure |
Standard CPAP
n=126 Participants
Use of a standard CPAP (continuous positive airway pressure) device with constant pressure for 4 weeks to improve breathing during sleep
Standard CPAP: Use of the REMstar Auto A-Flex in standard CPAP therapy mode
|
CPAP-Flex
n=131 Participants
Use of CPAP-Flex (continuous positive airway pressure) device with decreased pressure during expiration for 4 weeks to improve breathing during sleep
CPAP - Flex: Use of Philips Respironics REMstar Auto A-Flex in C-Flex mode
|
|---|---|---|
|
Adherence to CPAP Overall Study, Subjects With Low Nasal Resistance
|
1.81 Hours/night
Interval 1.44 to 2.18
|
1.55 Hours/night
Interval 1.22 to 1.88
|
Adverse Events
Standard CPAP
CPAP - Flex
Serious adverse events
Adverse event data not reported
Other adverse events
Adverse event data not reported
Additional Information
Dr. Jag Sunderram
Rutgers Robert Wood Johnson Medical School
Results disclosure agreements
- Principal investigator is a sponsor employee
- Publication restrictions are in place