Impact of Sleep Apnea on Diabetic Foot Wound.

Study Overview
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Brief Summary
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Sleep apnea syndrome (SAS) is a common comorbidity of type 1 and type 2 diabetes. A low transcutaneous oxygen tension (PtcO2) measured on the foot is pejorative prognostic factor for the healing of a diabetic foot wound. SAS causes intermittent nocturnal hypoxia and sympathetic overactivity. The investigators hypothesized that SAS could be a factor reducing the PtcO2.Therefore, the main objective of this study is to assess the variation in PtcO2 between the end of the night and midday in patients with -or at risk of- diabetic foot wound according to the presence or not of sleep apnea syndrome.The secondary objective is to address the microvascularisation of diabetic patients having foot wounds according to their status regarding sleep apnea syndrome.

Detailed Description
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The study is observational, cross-sectional. Presence of sleep apnea syndrome will be assessed on the same night than the main outcome, that is the difference in PtcO2 between 5:00 AM and 12:00AM. Microvascularisation will be assessed by Laser Speckle Contrast Imaging Analysis (LASCA). Sample size is estimated at 60 patients based on previous revascularisation studies having PtcO2 as main outcome. An intermediary analysis is planned after 40 inclusions.

Official Title
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Influence of Sleep Apnea Syndrome and Its Treatment by Positive Airway Pressure Therapy on Transcutaneous Oxygen Tension (PtcO2) in Patients With Foot Wound or at Risk for Foot Wound

Conditions
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Diabetic Foot, Sleep Apnea

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Types 1 or 2 or MODY diabetes with diabetic foot wound (or at risk of foot wound stage 2 and 3 (see reference PMID:18442189). Patients covered by social insurance Exclusion Criteria: Patients with sleep apnea syndrome previously treated by positive airway pressure therapy. Patients previously treated by additional oxygen therapy. Patient with unstable psychiatric disease

Ages Eligible for Study
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Minimum Age: 18 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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Foot-wound without SAS<br>patients with diabetic foot wound(or at risk of diabetic foot wound) without sleep apnea syndrome | |
| Foot-wound with SAS<br>patients with diabetic foot wound(or at risk of diabetic foot wound) with sleep apnea syndrome | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Transcutaneous oxygen tension (PtcO2) | Transcutaneous oxygen tension (PtcO2)is measured with a Radiometer TCM4 (Radiometer, Copenhagen, Denmark) device, on the dorsum of the foot at the base of the second metatarsal, or as close to this location as possible. Calibration is performed before each measurement. All measurements are performed in supine position after 20 min of rest. Room temperature is kept constant (around 21°C-24°C). Patients are asked to avoid smoking or drinking coffee for at least 2 h before investigations | Transcutaneous oxygen tension is assessed at the end of the night (5:00a.m) and at midday (12:00 a.m) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Diabetes, Sleep apnea, Diabetic foot, Microcirculation