Effect of a Very Low Calorie and Low Calorie Diet on Moderate to Severe Obstructive Sleep Apnea in Obese Adults

Study Overview
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Brief Summary
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The purpose of this study is to test the effectiveness of two different weight loss diets on obstructive sleep apnea (OSA) severity.

Detailed Description
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Sleep apnea is a sleep disorder in which breathing repeatedly stops and starts during sleep. The most common type is obstructive sleep apnea (OSA), which occurs when the muscles in your throat relax and block your airway during sleep. The most noticeable sign of OSA is snoring. OSA is a risk factor for other chronic conditions like type 2 diabetes, cardiovascular disease, and high blood pressure. Although anyone can develop OSA, it commonly affects people who are obese. The more someone weighs, the more likely the OSA is to be severe. Weight loss is typically recommended for overweight individuals to help improve OSA. However, not enough research has been done for doctors to be able make specific recommendations to their patients.

Official Title
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Effect of a Very Low Calorie and Low Calorie Diet on Moderate to Severe Obstructive Sleep Apnea in Obese Adults

Conditions
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Obstructive Sleep Apnea

Intervention / Treatment
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* Other: Low Calorie Diet
* Other: Very Low Calorie Diet
* Other: Standard Care


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: AHI score of ≥ 5 Body mass index (BMI) between 30 to 49.9 kg/m2 Exclusion Criteria: Report serious medical risk such as insulin-dependent diabetes, active cancer, recent cardiac event Currently or planning to become pregnant during the next 9 months Not weight stable (-4.6 kg) for 3 mos. prior to intake Report current participation in a weight reduction program involving diet or PA Unwilling to be randomized to 1 of 3 study groups Report symptomology of an eating disorder as determined by the Eating Attitudes Test Unable to participate in moderate intensity physical activity

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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Accepts Healthy Volunteers

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 |
| --- | --- |
| Experimental: Low Calorie Diet<br>Participants will take part in an experimental weight management program involving a low calorie diet (LCD), about 1200-1500 calories per day. | Other: Low Calorie Diet<br>* Weight management program designed around a low calorie diet.<br>|
| Experimental: Very Low Calorie Diet<br>Participants will take part in an experimental weight management program involving a low calorie diet (LCD), about 520-800 calories per day. | Other: Very Low Calorie Diet<br>* Weight management program designed around a very low calorie diet.<br>|
| Active Comparator: Standard Care<br>Participants will receive normal care. | Other: Standard Care<br>* Care provided that would normally be given to people meeting eligibility criteria for this study.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Apnea Hypopnea Index (AHI) | The AHI measures sleep apnea severity and represents the number of apnea and hypopnea events per hour. | Change from Baseline to Month 3 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Apnea Hypopnea Index (AHI) | The AHI measures sleep apnea severity and represents the number of apnea and hypopnea events per hour. | Change from Baseline to Month 9 | 
| Change in metabolic syndrome (MetS) risk factors | Risk factors to be measured include waist circumference, triglycerides, HDL-cholesterol, blood pressure, fasting glucose | Change from Baseline to Month 3 and Month 9 | 
| Change in Quality of Life | Participants will complete the Calgary Sleep Apnea Quality of Life Index (SAQLI) that will assess participants response to the intervention/treatment. | Change from Baseline to Month 3 and Month 9 | 
| Change in Daytime Sleepiness | Researchers will administer Epworth Sleepiness Scale. Results will be used to calculate daytime sleepiness changes for each participant. | Change from Baseline to Month 3 and Month 9 |