An observational study in Sleep Apnea, sponsored by University of Sao Paulo General Hospital. Completed at 1 site in Brazil. Open to participants aged 18 Years to 80 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2019-09-30.
Sponsored by University of Sao Paulo General Hospital · Observational
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.
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.
2,183 studies on the registry are indexed under Sleep Apnea Syndromes; 284 are open to participants now.
This study's enrollment of 300 is above the median of 109 across 659 observational studies indexed under Sleep Apnea Syndromes.
Browse Sleep Apnea Syndromes studies →University of Sao Paulo General Hospital is the lead sponsor of 608 studies on the registry; 97 are open to participants now.
Of its 8 completed or terminated interventional studies of FDA-regulated products, 0 (0%) have results posted.
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Consecutive patients referred to a university-based tertiary sleep referral centre.
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Exclusion Criteria:
Monitoring the apnea-hypopnea index (AHI) derived from PSG and the oxygen desaturation index (ODI) obtained by the Oxistar.
Sensitivity
Sensitivity of Oxistar device to detect apnea events compared to gold-standard polysomnography
Time frame: Night during the polysomnography exam
Specificity
Specificity of Oxistar device to detect apnea events compared to gold-standard polysomnography
Time frame: 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
Time frame: Night during the polysomnography exam
Bland-Altman Graph
The Bland-Altman graph evaluates the "agreement" between the gold-standard polysomnography and Oxistar device
Time frame: 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
Time frame: Night during the polysomnography exam
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)
Time frame: 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).
Time frame: Night during the polysomnography exam
Plan to share: No
This study is completed, as verified in Jul 2018. You cannot join it, but the record below documents what was studied.
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