Evolution With CPAP Treatment of a Cohort of Type 2 Diabetic Patients With Apnea-hypopnea Syndrome

Study Overview
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Brief Summary
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The main purpose of this study is to measure the evolution of hemoglobin A1c level after treatment with CPAP in a cohort of type 2 diabetes mellitus patients with poor glycemic control and associated moderate or severe obstructive sleep apnea.

Detailed Description
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Subjects with poorly controlled type 2 diabetes are a high cardiovascular risk group in which a high prevalence of moderate to severe sleep apnea is expected. Studies based on interstitial glycemic measurement demonstrate a reduction in glucose levels when treating sleep apnea with CPAP. Nevertheless, the effectiveness of CPAP in improving glycemic control has been questioned as most studies have failed to demonstrate a reduction in hemoglobin A1c (HbA1C) level over time. Most of these studies have limitations such as a short follow-up or a suboptimal fulfillment of CPAP treatment. We hypothesize that treating moderate to severe sleep apnea with CPAP will improve glycemic control (measured by HbA1C) at 14 weeks in good compliers and that this improvement will be sustained at one year. We aim to test this hypothesis in consecutive type 2 diabetes patients on stable treatment with HbA1c ≥7% in routine outpatient visits in our Diabetes, Nutrition and Endocrinology Unit. After providing informed consent, patients will be screened for sleep apnea by nocturnal oximetry followed by a diagnostic respiratory polygraphy. Those patients with obstructive sleep apnea with an apnea-hypopnea index ≥20 will be invited to enter the study. After a 3-month observation period without any intervention to rule out a potential influence of entering the study on HbA1C levels, patients will be treated with CPAP. HbA1C levels will be measured at baseline, after 14 weeks, and thereafter every 14 weeks until completing one year of treatment. Other endocrine, metabolic and cardiovascular risk variables will be determined at baseline and at 14 weeks of the intervention.

Official Title
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Evolution With CPAP Treatment of a Cohort of Type 2 Diabetic Patients With Moderate to Severe Apnea-hypopnea Syndrome and Poor Glycemic Control

Conditions
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Sleep Apnea, Type 2 Diabetes

Intervention / Treatment
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* Device: Continuous Positive Airway Pressure CPAP


Participation Criteria
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Eligibility Criteria
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Inclusion criteria: Type 2 diabetes on stable treatment for the last three months and HbA1C ≥ 7% Obstructive Sleep Apnea with and apnea-hypopnea index ≥20 Acceptance of a therapeutic trial with CPAP Exclusion criteria: Race: non caucasic Blood level of hemoglobin <10 in women or <11 in men or iron defitiency or hemoglobinopathy Glomerular filtration rate < 30 Habitual sleeping time <6 hours per night Nocturnal work, shift work or unsual sleeping schedule Primary severe insomnia or secondary to restless legs syndrome Major or non stable psychiatric disorder Treatment with corticosteroids Chronic respiratory disorders that may require corticosteroids or cause respiratory insufficiency or FEV1/FVC<0.7 with FEV1<50 in spirometry Predominant nocturnal hypoventilation pattern Cardiac failure Alcohol abuse Active CPAP treatment Previous surgery for sleep apnea Severe nasal obstruction Illiteracy

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 69 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
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Continuous Positive Airway Pressure<br>Continuous Positive Airway Pressure (CPAP) | Device: Continuous Positive Airway Pressure CPAP<br>* CPAP treatment<br>* Other names: no other name;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Hemoglobine A1C from baseline |  | 14, 28, 42 and 56 weeks after initial intervention. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Blood levels of fasting glucose from baseline |  | 14 weeks after initial intervention | 
| Self measured capillary glucose profile |  | 14 weeks after initial intervention | 
| Evening saliva collection for cortisol assay |  | 14 weeks after initial intervention | 
| Noninvasive 24-hour ambulatory blood pressure monitoring |  | 14 weeks after initial intervention. | 
| Analysis of urine to assess albumin to creatinine ratio |  | 0, 14, 28, and 56 weeks after initial intervention. | 
| Blood levels of fasting insulin |  | 14 weeks after initial intervention | 
| Blood levels of total cholesterol |  | 14 weeks after initial intervention | 
| Blood levels of cholesterol HDL |  | 14 weeks after initial intervention | 
| Blood levels of tryglicerids |  | 14 weeks after initial intervention | 
| International Physical Activity Questionnaire |  | 14 weeks after initial intervention | 
| Epworth Sleepiness Scale |  | 14 weeks after initial intervention | 
| SF-36 v2 Health Survey |  | 14 weeks after initial intervention | 
| subjective quantity and quality of sleep reported in a sleep log |  | 14 weeks after initial intervention | 
| Change in ratio albumine to creatinine from baseline |  | 14, 28, 42 and 56 weeks after initial intervention |