Hyperglycemic Profiles in Obstructive Sleep Apnea: Effects of PAP Therapy

Study Overview
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Brief Summary
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This is a randomized control trial in people with diabetes and obstructive sleep apnea who will be randomly assigned for 3 months to PAP therapy along with healthy lifestyle and sleep education or healthy lifestyle and sleep education.

Detailed Description
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Research over the last decade has shown that obstructive sleep apnea (OSA) is a common condition in people with diabetes. Observational and experimental evidence also indicates that intermittent hypoxemia and recurrent arousals in OSA may alter glucose metabolism and worsen glycemic control. However, the impact of treating OSA with positive airway pressure (PAP) therapy on glycemic variability and control is not well defined. Adequately powered randomized clinical trials have yet to be performed to demonstrate whether PAP therapy for OSA in diabetics can improve glycemic variability (and control), decrease blood pressure, and reverse endothelial dysfunction. The overarching goal of this study is to determine whether PAP therapy for OSA in diabetics leads to improvements in (a) glycemic variability as assessed by self-monitoring of blood glucose and continuous monitoring of glucose; (b) glycosylated hemoglobin; (c) blood pressure; (d) endothelial function; (e) serum and urinary biomarkers; and (f) dyslipidemia.

Official Title
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Hyperglycemic Profiles in Obstructive Sleep Apnea: Effects of PAP Therapy

Conditions
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Sleep Apnea, Diabetes

Intervention / Treatment
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* Device: REMStar Positive Airway Pressure
* Behavioral: LifeStyle Counseling


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Type 2 diabetics Age > 21 and ≤ 75 years Exclusion Criteria: Inability to consent or commit to the required visits Use of insulin or other injections for diabetes Weight change of 10% in last six months Use of oral steroids in the last six months Pulmonary disease (i.e., COPD) Renal or hepatic insufficiency Recent MI or stroke (< 3 months) Sleep-related hypoventilation Obesity-hypoventilation syndrome Morbid Obesity Occupation as a commercial driver or operator of heavy machinery Active substance use Untreated thyroid disease Pregnancy Any history of seizures or other neurologic disease Poor sleep hygiene or sleep disorder other than sleep apnea Central sleep apnea Variants of obstructive sleep apnea (e.g., REM-related OSA) Participants not suitable for the study based on the clinical judgment Use of any investigational drug within the past 30 days Participating in another study

Ages Eligible for Study
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Minimum Age: 21 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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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: REMStar Positive Airway Pressure<br>Positive pressure therapy is the standard of care for managing obstructive sleep apnea. | Device: REMStar Positive Airway Pressure<br>* Positive airway pressure therapy is the standard of care for managing obstructive sleep apnea<br>|
| Other: LifeStyle Counseling<br>Lifestyle guidelines developed by the American Diabetes Association for weight loss will be provided to all subjects. | Behavioral: LifeStyle Counseling<br>* Lifestyle guidelines developed by the American Diabetes Association for weight loss will be provided to all subjects.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Continuous Glucose Monitoring System Standard Deviation | Continuous Glucose Monitoring Metrics - change in standard deviation between baseline and three months. | Baseline and 3 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mean Difference in Systolic Blood Pressure | Mean difference between 3 months and baseline systolic blood pressures (in mmHg) by group. | Baseline and 3 months | 
| Change in Endothelial Dysfunction as Assessed by the Reactive Hyperemic Index | Endothelial function was measured by the EndoPAT device - difference at 3 months - baseline, by group. The outcome reported is the Reactive Hyperemic Index (RHI). The RHI is a measure of endothelial vasodilator function. The RHI is the post-to-pre occlusion peripheral arterial tone signal ratio in the occluded arm relative to the other arm, which is not occluded. Persons with worse endothelial function have a lower RHI score. Consequently, a low RHI indicates more endothelial dysfunction. A value of 1.67 or less is considered abnormal vascular tone. The reported lower and upper limits in adults with type 2 diabetes is 1.1 - 4.9. | Baseline and 3 months | 
| Heart Rate Variability |  | 3 months | 
| Change in the Epworth Sleepiness Scale | The Epworth Sleepiness Scale measures self-reported sleep propensity or daytime sleepiness. The range of the scale is 0 to 24 (integers only), with increasing values corresponding to increasing sleepiness. A cut-point of ≥ 11 is also sometimes used to differentiate those with pathological sleepiness (≥ 11) versus those without < 11. The difference between the three month final visit - the baseline visit score is reported by group | Baseline and 3 months | 
| Change in Post-Pre Meal Blood Glucose Levels | The difference from baseline to three months in self-reported in blood glucose levels before and after meals (mg/dL) (post-meal - pre-meal). Data is presented for breakfast, lunch, and dinner. | Baseline and 3 months | 
| Change in Glycosylated Hemoglobin A1c Level | Change in point-of-care hemoglobin A1c (%) after three months. | Baseline and 3 months | 
| Continuous Glucose Monitoring System Mean Amplitude Glucose Excursion | Mean Amplitude Glucose Excursion in mg/dL (difference between the peaks and troughs of glucose from continuous glucose monitoring at three months). | 3 months | 
| Continuous Glucose Monitoring System Standard Deviation | The standard deviation of the glucose from continuous glucose monitoring at three months. | 3 months | 
| Change in Continuous Glucose Monitoring System Mean Glucose | Continuous Glucose Monitoring Metric - change in average glucose level (mg/dL) from baseline to three months. | Baseline and 3 months |