Cognitive Behavioral Therapy to Increase CPAP Adherence in Veterans With PTSD
Phase: NA
Conditions: Obstructive Sleep Apnea, PTSD, Posttraumatic Stress Disorder
Sponsor: VA Office of Research and Development

COGNITIVE-BEHAVIORAL THERAPY FOR OBSTRUCTIVE SLEEP-APNEA 
TAPS STUDY PROTOCOL  
NCT02641496 
April 30, 2024 
 
 

INTRODUCTION 
The purpose of this study is to test a novel cognitive-behavioral therapy (CBT) intervention to 
increase continuous positive airway pressure (CPAP) treatment adherence for PTSD Veterans 
with a new diagnosis of obstructive sleep apnea (OSA). PTSD is a common, debilitating 
psychiatric consequence of exposure to trauma and a source of significant disability among U.S. 
war Veterans. The largest epidemiologic study of PTSD in Vietnam Veterans estimates that 15% 
of Vietnam Veterans suffer from PTSD [1].  Our research on OSA in Vietnam era Veterans found 
that 69% of the veterans in the sample had an AHI ≥ 10 [2].  OSA is likely present in 50% of 
middle-aged and older VA patients [2, 3].  The recurrent hypoxemia and sleep fragmentation 
associated with OSA can lead to neural injury and functional impairment. Efficacious treatments 
are available for OSA (e.g., CPAP); however, Veterans with OSA frequently fail to use them  [2, 
4, 5], leaving these Veterans at risk for cognitive dysfunction [6], deterioration of physical health 
[7], and negative functional outcomes [8].  Our long-term goal is to improve Veterans’ functional 
outcomes by improving adherence to CPAP.  If this intervention proves successful, it may 
represent an approach that could be applied to the rehabilitation of other chronic conditions with 
similar barriers to care.  
 
The reasons for low CPAP adherence include barriers related to discomfort in using CPAP and 
psychological barriers to behavior change [9].  A CBT treatment to improve CPAP adherence, 
CBT-OSA, has been successfully applied in civilian randomized controlled trials (RCTs) [10, 11].  
Our VA intervention would involve delivery of CBT-OSA to PTSD Veterans to foster long-term 
CPAP adherence.  The CBT-OSA treatment builds on the VISN 21 MIRECC’s expertise in CBT 
interventions [e.g., VA rollout of CBT-Insomnia] as well as on our current research on PTSD 
Veterans with OSA.  In this sample, the vast majority were not diagnosed with OSA prior to 
study entry; however, 69% of the participants had an AHI ≥ 10 [2].  Of the Veterans previously 
diagnosed with OSA, 63% were not using their CPAP.  Specifically, this will be a 1-year parallel-
group RCT involving 120 PTSD Veterans with a diagnosis of OSA.  All participants will receive 
treatment as usual in VA Pulmonary Service.  Participants in the active arm will receive CBT-
OSA from a trained Clinical Psychologist (CP).  The other arm will receive individual participant 
education from an Educator (ED), but not CBT-OSA.  Participants in both arms will receive 
weekly, individual sessions during the first 4 weeks of CPAP treatment and 3 booster sessions 
during the 1-year protocol.  These two arms will be referred to hereafter as the CBT-OSA and 
the Education groups.  
 
OBJECTIVES AND END POINTS 
Objective 1. (Primary) Effect of CBT on CPAP usage. We hypothesize that the CBT-OSA group 
will use CPAP more hours per night on average than the Education Group.  ANOVA will be 
used to test group differences over time in hours of “mask-on” CPAP usage per night. Primary 
endpoint: mean of Days 335-365. 
Objective 2. (Secondary) Effect of CBT on Self-reported Everyday Activities, Mood and 
Quality of Life.  We hypothesize that after initiating CPAP treatment, Veterans in the CBT-OSA 
group will report more improvement in the ease of performing everyday activities compared to 
that reported by those in the Education group.  ANOVA will be used to test group differences 
over time in the total score on the Functional Outcomes of Sleep Questionnaire (FOSQ; [12], 
at Days 365 (endpoint).   
Objective 3. (Secondary) Effect of CBT on Cognitive Outcomes.  We hypothesize that the 
CBT-OSA group will have better cognitive outcomes than the Education group over time.  
ANOVA will be applied to the California Verbal Learning Test, Delayed Free Recall Score with 
the primary endpoint at Day 365. 
Objective 4. (Secondary) Effect of CBT on PTSD.  We hypothesize that the CBT-OSA group 
will have fewer PTSD symptoms than the Education group over time.  ANOVA will be used to 

test group differences over time in the total score on the PTSD Checklist for DSM-5 (PCL-5), 
measured at Days 0, 21, 365. Primary endpoint is Day 365.  
 
Table 1: Description of Measures 
Primary Outcome Measure: 
 
Hypothesis 1 Effect of CBT on CPAP adherence 
 
Objectively Measured CPAP Usage.  The times when 
the mask is on the face are recorded and stored by the 
CPAP device ResScan™ data card. 
The primary outcome measure is an objective 
measure: the average of CPAP mask-on time for 
the last 30 days of the 1-year RCT (Days 335-
365).  
 
Secondary Outcome Measures: 
  
Hypothesis 2 Effect of CBT on Self-reported 
Everyday Activities, Mood and Quality of Life 
 
The Functional Outcomes of Sleep Questionnaire 
(FOSQ) [12] is a self-report measure of how much 
sleepiness impacts everyday activities and quality of 
life in multiple domains of function.   
 
  
The FOSQ is designed to be given to individuals 
with a sleep disorder.  In a 2011 VA clinical trial, 
FOSQ scores improved significantly in Veterans 
randomly allocated to APAP (n=105) and those 
allocated to CPAP (n=96), p’s < .0001.  
Hypothesis 3. Effect of CBT on Cognitive 
Outcomes.   
 
A cognitive battery known to be sensitive to OSA, and 
relevant to long-term CPAP adherence [9] will include 
our primary outcome measure, the California Verbal 
Learning Test [13], Long Delay Free Recall.   
The purpose of the battery is to assess if 
changes in cognitive function occur, dependent 
on intervention group status. Baseline scores will 
also be used in supplementary data analyses on 
Moderators of treatment response to identify 
characteristics of patients who are best served 
by a CBT approach. 
Hypothesis 4. Effect of CBT on PTSD. 
 
PTSD Checklist for DSM-5 (PCL-5) [14].  PCL-5 is a 
20-item self-report measure for PTSD based on DSM-
5.   
The PCL-5 is designed to assess if the proposed 
treatment has any effects on PTSD symptoms.  
 
 
 

 
RESEARCH DESIGN AND METHODS 
PROCEDURES INVOLVING ELIGIBLE PARTICIPANTS 
Study Timeline 
Schedule of Visits and Key Assessments 
 
 
Consent Screen BL* 
Pre- 
Intervention 
Phase 
Early 
Intervention 
Phase 
Booster Session 
Phase 
Final 
Booster 
Session 
Treatment Session  
 
 
 
1 
Start 
CPAP 
2 
3 
4 
 
5 
6 
7 
8 
Procedure Day 
 
-28 to -14 
0 
 
7 
14 
21 
 
90 
180 
270 
365 
Consent 
X 
X* 
 
 
 
 
 
 
 
 
 
 
 
Med Hx review 
 
X 
X* 
 
 
 
 
 
 
 
 
 
X 
Blood Sample  
 
 
 
X 
 
 
 
 
 
 
 
 
 
Self-reports  
 
X 
X* 
 
 
 
 
X 
 
X 
X 
X 
X 
Semi-structured 
Clinical Interview  
 
X 
X* 
 
 
 
 
 
 
 
 
 
X 
Cognitive Battery 
 
X 
X* 
 
 
 
 
 
 
 
 
 
X 
Self-Efficacy Measure 
for Sleep Apnea  
 
 
 
X 
 
 
 
X 
 
X 
X 
X 
X 
Working Alliance 
Inventory SAT** 
 
 
 
X 
 
X 
X 
X 
 
X 
X 
X 
X 
 In-clinic treatment 
sessions 
 
 
 
X 
 
X 
X 
X 
 
X 
X 
X 
X 
CPAP Usage  
(Measurement 
Periods) 
 
 
 
 
X 
 
 
 
 
 
 
*If Baseline (BL) visit is needed,  it will include the activities that were not completed during the 
screening visit 
 
**WAI modified to apply to Sleep Apnea Treatment (SAT). 
 
 After Session 1 (Day 0), participants will be called by their CP or ED daily for one week to 
provide early and consistent intervention.  
 
 

OVERVIEW    
Aims and Design of the Study.  To test the efficacy of CBT-OSA in improving CPAP usage, the 
design will be a 2-arm RCT: 120 PTSD Veterans who are recently diagnosed with OSA and 
newly initiating CPAP will be allocated by 1:1 random assignment to either the ‘CBT-OSA’ group 
or the Education group.  All Veterans will participate in usual care in VAPAHCS Pulmonary 
Service which is considered standard of care.  During the 1-year study, the CBT-OSA arm will 
include seven individual, in-clinic intervention sessions with a CBT-trained Clinical Psychologist 
(CP): one session prior to starting CPAP (Session 1-Day 0), followed by three in-clinic sessions 
within the first four weeks of initiating CPAP (Session 2-Day 7; Session 3-Day 14; Session 4-
Day 21) and 3 booster sessions (Session 5-Day 90; Session 6-Day 180; Session 7-Day 365).  
Education participants will receive equivalent amounts of contact with a trained Educator. All 
participants will receive the same CPAP devices and appropriate follow-up as usual care at the 
VAPAHCS. 
     To test the efficacy of CBT-OSA, the two groups will be compared for differences in average 
hrs/day of CPAP use.  We are particularly interested in the difference between the groups in 
CPAP usage during the final 3 months of this 1-year study.  Group differences in average 
hrs/day of CPAP use during Weeks 0-4 will be examined as a secondary outcome.  
     To determine if CBT-OSA therapy translates to better participant functional outcomes than 
those in the Education group, each participant will be asked to fill out the Functional Outcomes 
of Sleep Questionnaire [FOSQ; 12] on 3 occasions: before the first and final weekly CBT-OSA 
treatment sessions (Day 0, 21) and before the final booster session (Day 365) after initiating 
CPAP treatment.  Each participant will also undergo a cognitive battery on 2 occasions: at 
Baseline (BL; before initiating CPAP) and 1 year later (Day 365). The entire project is expected 
to take 4 years).  
 
PARTICIPANTS  
 
Veterans will be recruited from the VAPAHCS weekly 1 hour outpatient OSA Group Clinic. The 
majority of attendees are newly diagnosed with OSA by a Board Certified Sleep Medicine 
Physician.  During the group appointment, Veterans receive education about OSA and treatment 
from a sleep medicine physician (using a PowerPoint presentation).  A Q&A session follows the 
physician’s presentation.  At the conclusion of Q&A, Veterans will be introduced to the study.  
The study will be described as research that could help improve the participant’s ability to use 
CPAP.  Interested Veterans will participate in a confidential screen for eligibility within 4 weeks of 
starting CPAP. Veterans can choose to initiate or decline CPAP treatment.  While participating in 
the proposed project, they will continue to have access to their usual care.     
 
Inclusion and Exclusion Criteria 
Overview. The inclusion/exclusion criteria are designed to select PTSD Veterans who have a 
diagnosis of mild to severe OSA. Patients with dementia or severe psychiatric illness will be 
excluded because they may be less likely to complete the study or follow the protocol 
procedures.  Veterans with mild comorbid conditions will not be excluded because comorbidities 
are common in Veterans, and we want to obtain results that would be generalizable to typical VA 
PTSD patients.   
     In accordance with AASM’s Practice Parameters for the use of portable monitoring devices 
for titrating pressures and treating adults with OSA, Veterans with clinically significant comorbid 
cardiac, pulmonary or neurologic disease will be excluded [15].  In general, OSA patients with 
significant comorbid cardiorespiratory disease or known/suspected nocturnal hypoventilation 
(e.g. neuromuscular disease, spinal cord injury, morbid obesity, chronic opioid use) are 
prescribed BPAP [16].  Thus, we plan to exclude these patients to standardize the 
administration of CPAP therapy and focus our research efforts on improving adherence to 
CPAP. 

 
Inclusion Criteria – Each participant must meet the following criteria for inclusion in the 
study: 
• Male or Female Veterans of any racial or ethnic group  
• Age 18 years old and older  
• OSA diagnosis by a board-certified Sleep Medicine physician, described below in OSA Work-
up and Diagnosis section  
• AHI ≥ 5 events per hour   
• PTSD participants will be positive for lifetime and/or current PTSD, related to combat 
experience and have a diagnosis of chronic current and/or lifetime PTSD as measured by the 
Clinician Administered PTSD Scale (CAPS)  
• Capable of giving informed consent for the study; able to read and write English; willing and 
able to comply with study requirements and restrictions 
• Nondemented by screening assessment of global cognitive function  
• Sufficient visual and auditory acuity for cognitive testing 
 
Exclusion Criteria – Participants will be excluded from the study if any of the following 
criteria apply: 
Sleep 
• Diagnosis of Central Sleep Apnea (CSA) (CAI ≥ 5 per hour) or Complex/Treatment Emergent 
CSA. 
• Comorbid sleep disorder (e.g. narcolepsy, restless leg syndrome, periodic limb movement 
disorder, idiopathic hypersomnia or REM Behavior disorder) (excluding insomnia)  
• Working night, rotating or split [period of work, followed by break, and then return to work]; 
shift work within 1-month of screening or plan to work these shifts during study; Occupations 
where participants regularly experience jet lag or have irregular work schedules. 
 
Other Medical 
• Unstable or moderate to severe chronic illness including systolic congestive heart failure 
(LVEF <45%), COPD (FEV1<80% predicted), uncontrolled asthma, severe liver disease 
(modified Child-Pugh score >6), end stage renal disease requiring hemodialysis or history of 
systemic illness affecting CNS function (e.g. liver failure, kidney failure, congestive heart 
failure, systemic cancer).   
• Any current clinically significant cardiovascular, respiratory, neurologic, hepatic, 
hematopoietic, renal, gastrointestinal or metabolic dysfunction unless currently controlled and 
stable.  Any solid organ transplantation.   
• Known or suspected neuromuscular disease (e.g. amyotrophic lateral sclerosis, spinal cord 
injury) 
• History of head injury within past year, or history of loss of consciousness > 24 hours 
• History of other neurological disease (e.g., history of stroke, transient ischemic attacks, 
multiple sclerosis, Parkinson’s disease) 
• Current or recent (prior 3-months) use of systemic steroid medication, supplemental oxygen, 
opioid medication, stimulant medication (e.g. modafinil, methylphenidate, amphetamine), 
hypnotic medication (e.g. zolpidem, eszopiclone), sedating antihistamine medication, 
dopamine agonists (e.g. ropinirole), excessive caffeine intake (>800 mg/day or >8 cups of 
coffee/day) or toxicology evidence of illicit substance use in the prior month.  Such 
medications could add variability to behavioral outcomes such as the FOSQ, and diminish the 
clarity of results. 
• Judged by the investigators to be unable or unlikely to follow the study protocol (e.g., 
dementia). 
 
Psychiatric  
• Current or lifetime history of a psychiatric disorder with primary psychotic features  
• Current or lifetime bipolar disorder; Prominent suicidal or homicidal ideation 

• Current exposure to trauma, or exposure to trauma in the past 3 months 
• Current or within the past 30 days drug abuse or dependence (except nicotine). 
• Presence of acute or unstable psychiatric condition(s) that requires referral for treatment.  
• Current or expected cognitive behavior therapy for another condition (e.g. insomnia, anxiety). 
 
Other 
• A clinical history or participation in other research that would interfere with the objectives of 
this study. 
• Any other medical, social, or geographical factor that would make it unlikely that the 
participant would comply with the study procedures (e.g. lack of permanent residence or 
history of noncompliance).  
 
OSA Work-up and Diagnosis. Consultations are triaged, such that, a decision is made 
regarding the level of sleep work-up recommended for that patient within 2 days of receiving a 
consult.  Typically, a ‘Level 3’ sleep study is recommended (i.e., an unattended cardiopulmonary 
sleep study with a portable monitor) to be performed overnight at the VAPAHCS. Prior to the 
sleep study, the Veteran is mailed a packet that includes information about sleep problems, an 
explanation of the diagnostic procedures recommended, and relevant questionnaires (e.g., 
Epworth Sleepiness Scale, Beck Depression Inventory-II). Apneas and hypopneas are defined 
using the American Academy of Sleep Medicine’s recommended criteria [17]. Also, as is the 
case in many large VHA facilities, there are not resources to perform an in-laboratory titration of 
the pressure setting.  Veterans that are prescribed CPAP treatment will receive a Resmed 
model PAP device. 
 
SCREENING PROCEDURES AND DETERMINATION OF STUDY ELIGIBILITY 
 
Initial contact with prospective participants will occur at the OSA Group Clinic where interested 
Veterans will receive an IRB approved study flyer and consent form to review.  The text of the 
consent form and phone screen provides permission to review medical records in CPRS and 
mentions that a member of the research team will telephone participants to review their medical 
history.  Screening will proceed in two phases: 1) a brief telephone interview to determine if the 
veteran is likely to meet inclusion and exclusion criteria, 2) followed by a comprehensive in-clinic 
screening visit.  After the brief telephone screening interview, if the medical and psychiatric 
criteria appear to be met, an in-clinic screening (SC) visit with the Study Coordinator will be 
scheduled.   
 
Measure 
Description 
MMSE 
Cognitive Screen 
SCID 
Psychiatric Screen 
CAPS-5 [18] 
PTSD  Screen 
 
At the screening visit, the participant’s medical record and list of medications will be 
reviewed for evidence of exclusionary medical (e.g., hepatic, renal, congestive heart failure) and 
neurologic disorders.  Unstable or clinically significant conditions will receive prompt clinical 
follow-up by psychologists and physicians of the VAPAHCS Memory Clinic. 
The results of all of the screening assessments will be reviewed with Key Personnel. After 
consensus determination for study eligibility, the Study Coordinator will contact the participant to 
schedule a Baseline visit (if eligible), or provide appropriate referral and explanation (if deemed 
ineligible).   
 
Enrollment, Randomization, and Baseline Measures 

RCT Enrollment and Randomization.  After the two-phase screening, eligible participants will be 
invited to participate and, if willing, scheduled to begin within 3 to 4 weeks of the completion of 
the screening visit.  The Baseline visit and Session 1 (Day 0) will be carefully coordinated with 
Pulmonary staff for the participants who will receive their CPAP on the day of Session 1 (before 
the start of Session 1).  All eligible participants will be randomized by the Data Manager to one 
of the two intervention arms: “CBT-OSA” or “Education” and notify the treating CP or ED, 
respectively.   
 
Baseline Measures. The Coordinator will administer a cognitive battery  
 
Adherence Intervention: CBT-OSA vs. Education 
      All CBT-OSA treatment will be done by a CBT-trained Clinical Psychologist and aimed at 
changing a participant’s behaviors and cognitions related to CPAP use.  These cognitive and 
behavioral interventions will be taught in the initial four weekly clinic sessions and reinforced in 
three booster sessions.  To increase motivation and positive expectations, CBT-OSA will also 
include treatment goals relevant to the particular participant’s condition.   
The treating CP will work closely with the PI for clinical supervision and protocol adherence.  
The CP will learn the CBT-OSA intervention and will be practiced in achieving treatment fidelity. 
The CP will work with the participant individually (during certain sessions with the participant 
and bed partner).   
The Education arm will focus on educational material (e.g., sleep health, sleep disorders, 
PTSD, cardiovascular health) over four weekly sessions and reinforced in three booster 
sessions.  All participants will have equal opportunities for contact time with research staff. 
Participants will bring their CPAP to all sessions to use for exposure intervention (if in CBT-OSA) 
and to allow study staff to download CPAP data.  
 
Pre-CPAP Intervention Phase 
On Day 0, prior to starting or reinitiating CPAP (Pre-CPAP Intervention Phase), the Veteran will 
complete the following self-report measures: FOSQ, ESS, PCL-5, BDI-II, SEMSA and WAI-SAT. 
Then, participants in both arms, will have one individual in-clinic session (Session 1-Day 0) with 
their assigned CP or ED.   
 
 
MEASURES   
Consented Veterans who have been determined eligible and are willing to enter the RCT will be 
administered the measures described in Table 1 above. 
 
 
DATA ANALYTIC PLAN 
Hypothesis 1. (Primary Outcome) Effect of CBT on CPAP usage. We hypothesize that the 
CBT-OSA group will use CPAP more hours per night on average than the Education group.  An 
ANCOVA will be used to compare performance on the primary measure [(the average of CPAP 
mask-on time for the last 30 days of the 1-year RCT (Days 335-365); a continuous variable)] by 
Group (CBT-OSA versus Education).  The analyses will be an intention to treat design using 
multiple imputation for missing data [19].  We will perform multiple regression analyses to 
identify potential covariates (e.g., AHI prior to treatmen1, daytime sleepiness) which will be 
considered in the analysis. In a RCT, we assume that the groups will be apportioned relatively 
equally on relevant background variables, but we will verify this by analyzing specific baseline 

variables (e.g., gender, age, education).  We do not propose to enter all possible background 
variables as covariates into this analysis; however, we will perform multiple regression analyses 
to identify significant covariates. We will then include those variables in the ANOVA as 
covariates. 
 
Hypothesis 2-4. (Secondary Outcomes) Effect of CBT on Self-reported Everyday Activities, 
Mood and Quality of Life, Cognitive Outcomes and PTSD.  Secondary analyses will be 
conducted to compare performance between groups at Day 365 on relevant measures listed in 
Table 4 using the same statistical approach as Hypothesis 1.  
 
Hypothesis 2. Effect of CBT on Self-reported Everyday Activities, Mood and Quality of Life.  
We hypothesize that after initiating CPAP treatment, Veterans in the CBT-OSA group will report 
more improvement in the ease of performing everyday activities compared to that reported by 
those in the Education group. An ANOVA will be used to compare performance on the FOSQ 
Total Score (continuous variable) by Group at Day 365.  
 
Hypothesis 3. Effect of CBT on Cognitive Outcomes.  We hypothesize that the CBT-OSA group 
will have better cognitive outcomes than the Education group over time.  An ANOVA will be 
used to compare performance on CVLT Delayed Free Recall Score (continuous variable) by 
Group at Day 365.  
 
Hypothesis 4. Effect of CBT on PTSD.  We hypothesize that the CBT-OSA group will have 
fewer PTSD symptoms than the Education group over time.  An ANOVA will be used to 
compare the PCL-5 Total Score (continuous variable) by Group at Day 365. Potential covariates 
relevant to Hypotheses 2-4 will be treated as for Hypothesis 1.  
 
   
 
 

 
 

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