Validation of Sleep Apnea Diagnosis Device

Study Overview
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Brief Summary
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Obstructive sleep apnea (OSA) is common and largely underdiagnosed disease. The standard method for the diagnosis of OSA is a complete night polysomnography (PSG). Simple methods for OSA diagnosis are necessary. The overnight oximetry with the oxygen desaturation index (ODI) has been largely investigated as a diagnostic test for OSA but its accuracy remains undefined. The aim of our study is to evaluate if an wireless polygraph (Oxistar) is accurate to diagnosis OSA in patients referred to a Sleep Lab.

Detailed Description
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Consecutive patients referred to the sleep laboratory with suspected diagnosis of OSA underwent in-laboratory polysomnography (PSG) and simultaneously wireless polygraph. The PSG oximeter and the wireless polygraph were worn on different fingers of the same hand. All sleep studies were reviewed by one blind investigator according the 2017 American Academy of Sleep Medicine recommendations. The number of desaturations from wireless polygraph at the 3 predefined threshold levels (of ODI-2%, ODI-3%, or ODI-4%) was derived automatically using proprietary algorithm. Moderate to severe OSA was defined as AHI ≥ 15 events/h. The diagnostic accuracy of ODI-2%, 3%, and 4% for the diagnosis of moderate-severe OSA were calculated for cut-off values from 1 to 20 desaturation events/h. The sleep actimetry was compared with the sleep stages from PSG, most of the statistical metrics applied for diagnosis were used to evaluate the applicability of this proposed method. Finally, the snoring events computed by the smartphone application were compared with the events heard by a specialist and the statistical comparison metrics were evaluated.

Official Title
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Validation of a Wireless Wearable Sensor Using Mobile Technology and Cloud Computing for the Diagnosis of Sleep Apnea

Conditions
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Sleep Apnea

Intervention / Treatment
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* Diagnostic Test: Polysomnography (PSG) and wireless sensor Oxistar


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: referred by medical staff for an overnight assessment for suspected sleep apnea Exclusion Criteria: polysomnography for the CPAP titration

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 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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Arms and Interventions

| Intervention/Treatment |
| --- |
|Diagnostic Test: Polysomnography (PSG) and wireless sensor Oxistar|Monitoring the apnea-hypopnea index (AHI) derived from PSG and the oxygen desaturation index (ODI) obtained by the Oxistar.|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Sensitivity | Sensitivity of Oxistar device to detect apnea events compared to gold-standard polysomnography | Night during the polysomnography exam | 
| Specificity | Specificity of Oxistar device to detect apnea events compared to gold-standard polysomnography | Night during the polysomnography exam | 
| Area under the curve (AUC) | AUC from ROC curves reflects the accuracy of Oxistar device to detect apnea events compared to gold-standard polysomnography | Night during the polysomnography exam | 
| Bland-Altman Graph | The Bland-Altman graph evaluates the agreement between the gold-standard polysomnography and Oxistar device | Night during the polysomnography exam | 
| Interclass Correlation Coefficient (ICC) | ICC measures the reliability of measurements or ratings between the gold-standard polysomnography and Oxistar device | Night during the polysomnography exam | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Sleep Actigraphy | Actigraphy is the continuous measurement of activity or movement with the use of a small device called an actigraph. Periods of movement suggest wakefulness while those of relative stillness would likely correspond to sleep or quiescence. The Oxistar has a embeded actigraph whose data will be compared with the sleep stage scoring from polysomnography (PSG), the gold standard for sleep assessment. Epoch-by-epoch (30 seconds) agreement between the actigraph and PSG will be assessed by calculating sensitivity, specificity, accuracy, area under the curve (AUC), Bland-Altman graph and interclass correlation coefficient (ICC) | Night during the polysomnography exam | 
| Number of snoring events per hour of register (snoring/h) | Snoring is one of the signs suggestive of obstructive sleep apnea and has recently been considered as having great diagnostic potential. The smartphone application (app) through microphone performs the recording and the characteristics extraction of the patient's audio during sleep (register time). A multilayer perceptron (MPL) neural network classifies the event as snoring or non-snoring. Lastly, the amount of snoring occured is accounted and divided by the register time leading to the number of snoring/h. The agreement between snoring/h measured by the app and the heard by a specialist will be assessed by calculating sensitivity, specificity, accuracy and area under the curve (AUC). | Night during the polysomnography exam | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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oxygen desaturation index (ODI), sleep actimetry, snoring, sleep apnea, polygraph, home sleep apnea test (HSAT), apnea hypopnea index (AHI), portable monitor