Sleep Apnea Intervention for Cardiovascular Disease Reduction (BestAIR)

Moderate to severe sleep apnea (a high number of breathing pauses on a sleep study) is a common health problem that is often associated with loud snoring and sleepiness.The medical term for this problem is obstructive sleep apnea (OSA). People with OSA often have an increased risk for developing heart disease or may already have a diagnosis of heart disease. A clinical research study is being conducted at Brigham and Women's Hospital and Beth Israel Deaconess Medical Center to compare the effects of continuous positive airway pressure (CPAP) to conservative medical therapy with participation in one of four groups:

• CPAP Therapy Group: Standard medical treatment for sleep apnea, with CPAP mask worn during sleep. Participants randomized to either Respiratory Therapist (RT)only or RT with Cognitive Behavioral Therapist.
• Alternative CPAP Group: Different air delivery level from mask than CPAP Therapy Group. RT meetings.
• Conventional Medical Therapy (CMT) Group: Receive one year supply of nasal strips and follow guidelines for how to change sleep habits to minimize apnea.Frequent follow-up support with research coordinator.

The sleep doctor will have indicated that a potential participant is an appropriate candidate to receive CPAP or CMT as acceptable approaches to treat his/her sleep apnea. Participants will be recruited between the ages of 45-75 years who have diagnosed heart disease or between 55-75 years for those who have risk factors for developing heart disease.

This is a 12 month study to evaluate alternative ways to address the potential for OSA treatment to reduce heart disease and to identify those features that would strengthen a later, large-scale randomized controlled trial.

We propose to conduct a planning study to evaluate alternative study design features that address the potential for Obstructive Sleep Apnea (OSA) treatment to reduce cardiovascular disease (CVD) and to identify those features that would strengthen a later, large-scale Phase 3 randomized controlled trial (RCT). For this pilot study, we will recruit approximately 225 patients presenting to a sleep clinic with moderate to severe OSA and with CVD risk factors or established CVD. After a two week run-in period, we aim to randomize 150 participants to one of four arms, two of which use active continuous positive airway pressure (CPAP) and two of which are control conditions. All include conservative medical therapy (CMT). The active groups are: 1) active CPAP treatment delivered using standard respiratory therapist (RT) adherence education and support and 2) active CPAP treatment administered using adherence education and support delivered by a RT and enhanced by behavioral promotion intervention. The control arms are: 1 ) sham-CPAP and 2) CMT alone.

• Behavioral: Conservative Medical Therapy
  Participants in this group receive only CMT as the intervention. They will be provided ~30 minutes of instruction on sleep hygiene and healthy lifestyle guidelines using a standardized slide set and set of illustrated fact sheets. Each subject's sleep routine will be reviewed to identify appropriate bed and wake times that provide a consistent schedule and allow for at least 7 hours of time in bed per night. Habits that may impact sleep, close to bedtime, will be reviewed with appropriate guidance on how to minimize sleep disrupting exposures.Subjects will be provided external nasal dilator strips and advised on how to maximize sleep time in a non-supine position.
• Device: Active PAP with Respiratory Therapy Support
  Subjects will receive continuous positive airway pressure, adjustment to pressure made by a respiratory therapist (RT) when needed. Subjects will have an in person visit with the RT one week after start of CPAP and at 4 and 8 months. Additional support will be by phone at specified time points.
• Behavioral: Active PAP with Behavior Modification
  Participants meet with the Respiratory Therapist and a behavioral interventionist at the time of PAP prescription and one week later and at the 4 month and 8 month visits with the RT.
• Device: Sham PAP
  These participants will return to the sleep center one week after randomization. The core intervention includes education on PAP and mask use; side effects are addressed and feedback on PAP use is provided.Conservative medical therapy is also provided.

• Active Comparator: Conservative Medical Therapy
  Approximately 30 minutes of instruction on sleep hygiene and healthy lifestyle guidelines, including diet and activity. Assessment of sleep habits. Provision of external nasal dilator strips and advise on how to maximize sleep time. All participants will receive this as part of their intervention.
  Intervention: Behavioral: Conservative Medical Therapy
• Sham Comparator: Sham-PAP
  In addition to receiving conservative medical therapy, participants in this treatment arm will receive a PAP device, including a heated humidifier, ramp and expiratory relief for the duration of the intervention. After randomization, participants in this arm will meet with a respiratory therapist who will fit the PAP interface and provide instruction on the use of the device and education on its use.
  Intervention: Device: Sham PAP
• Active Comparator: Active PAP with RT Support
  In addition to receiving CMT, participants in the arm will receive a PAP device with heated humidifier, ramp and expiratory relief for the duration of the intervention. Titrations will occur according to routine clinical protocol. After randomization,, participants will meet with a respiratory therapist who will fit the PAP interface, provide instruction and receive a core adherence intervention which includes education and provides feedback on PAP use based on adherence data available through wireless telemonitoring of PAP use. Meeting with the RT is scheduled one week after initiating PAP to make adjustments. Then, alternate meetings with the RT by phone and in person are scheduled at quarterly intervals (so that contacts occur bi-monthly).
  Intervention: Device: Active PAP with Respiratory Therapy Support
• Active Comparator: Active PAP with Behavioral Modification
  In addition to receiving CMT and RT-guided adherence support, participants randomized to active PAP with BPA intervention would meet with a behavioral interventionist at the time of PAP prescription and one week later, and then at 4 and 8 month visits (scheduled at the same time as with the RT). Participants would also speak with the behavioral interventionist 6 times over the course of the study after beginning CPAP.
  Intervention: Behavioral: Active PAP with Behavior Modification

Inclusion Criteria:

• Obstructive apnea hypopnea index (AHI) ≥ 15
• Age 45-75 years, or 55 to 75 yrs if without established Cardiovascular Disease (CVD)
• Ability to provide informed consent, with the patient and physician acknowledging accepting uncertainty on the role of PAP in CVD prevention.

• Established CVD,or having diabetes mellitus, defined by one or more of the following:

  1. Prior myocardial infarction
  2. Coronary artery revascularization procedure (≥4 months before study entry)
  3. Angiographically documented stenosis (>70%) of a major coronary artery
  4. Prior ischemic stroke without major functional impairment
  5. Diabetes mellitus treated with medication or ≥ 2 fasting glucose levels ≥ 126 mg/dl

OR

Three or more of the following established CVD risk factors:

1. Hypertension treated with medications or systolic BP > 140 or diastolic BP > 90 on ≥ 2 occasions
2. Male sex
3. BMI ≥ 30
4. Total cholesterol > 240 mg/dl or LDL cholesterol > 160 mg/dl or HDL < 45 mg/dl
5. > 10 pack years of smoking

Exclusion Criteria:

• Diagnosed heart failure with known cardiac ejection fraction of < 35% or NYHA class 3 or 4 status; Less than 4 months since MI, stroke or revascularization procedure
• Poorly controlled hypertension (>170/>100)
• Prior stroke with functional impairment interfering with ability to complete the protocol
• Severe uncontrolled medical problems or medications that may influence measurements or impair ability to participate in the study exams (e.g. oral steroids; chronic opioid use; self- reported chronic kidney disease or, if measured, creatinine > 2.5 mg/dl of GFR < 30; anemia with Hgb < 10, etc.)
• Resting oxygen saturation < 90% or nocturnal oxygen saturation <85% for > 10% of the sleep period; Use of prescribed PAP for sleep apnea within the prior 2 years
• Report of inability to spend >6 hrs in bed
• Any use of prescribed PAP for sleep apnea
• Severe sleepiness defined by an Epworth Sleepiness Score of >14 or report of falling asleep driving in the prior 2 years
• Working as a professional driver
• Central sleep apnea, with >50% of respiratory events classified as central apneas
• Refusal to consider PAP use after an initial split-night PAP study (pre-randomization)