PSG-Audio, a scored polysomnography dataset with simultaneous audio recordings for sleep apnea studies.

The sleep apnea syndrome is a chronic condition that affects the quality of life and increases the risk of severe health conditions such as cardiovascular diseases. However, the prevalence of the syndrome in the general population is considered to be heavily underestimated due to the restricted number of people seeking diagnosis, with the leading cause for this being the inconvenience of the current reference standard for apnea diagnosis: Polysomnography. To enhance patients' awareness of the syndrome, a great endeavour is conducted in the literature. Various home-based apnea detection systems are being developed, profiting from information in a restricted set of polysomnography signals. In particular, breathing sound has been proven highly effective in detecting apneic events during sleep. The development of accurate systems requires multitudinous datasets of audio recordings and polysomnograms. In this work, we provide the first open access dataset, comprising 212 polysomnograms along with synchronized high-quality tracheal and ambient microphone recordings. We envision this dataset to be widely used for the development of home-based apnea detection techniques and frameworks.

Corneal Endothelial Morphology and Thickness Alterations in Patients With Severe Obstructive Sleep Apnea-Hypopnea Syndrome.

PURPOSE: To investigate central endothelial cell density (ECD), morphology, and central corneal thickness (CCT) in patients newly diagnosed with severe obstructive sleep apnea-hypopnea syndrome (OSAHS) and to determine the correlation between these parameters and OSAHS severity. METHODS: This prospective, comparative case series was conducted in a university ophthalmology clinic. In total, 51 patients recently diagnosed with severe OSAHS (apnea-hypopnea index above 30) and a paired, age and sex-matched control group of 44 healthy individuals were enrolled. After detailed ophthalmologic examination, specular microscopy measurement was performed for all participants. Central ECD, average cell area, coefficient of variation (CV) of cell area, hexagonal cell appearance ratio (% Hex), and CCT were compared between the groups. The Pearson correlation test was also used to assess the influence of the polysomnographic findings, that is, the proportion of each stage of sleep, apnea-hypopnea index, SpO2, mean and maximum duration of apneas, oxygen desaturation index, and arousal index on corneal endothelial morphometric parameters and CCT. RESULTS: A total of 190 eyes were examined: 102 eyes of patients with severe OSAHS and 88 eyes of the control group. The mean ECD, CV, % Hex, and CCT values in the OSAHS group were 2439.25 ± 344.36 cells/mm, 41.41 ± 11.62, 45.22 ± 7.06%, and 533.88 ± 40.53 µm, respectively. ECD and CCT did not significantly differ between the groups (P = 0.46, P = 0.55, respectively). CV value was significantly higher (P = 0.009), whereas the %Hex was significantly lower (P = 0.01) in the OSAHS group. We observed a significant negative correlation between CCT and REM sleep percentage (P = 0.005). CONCLUSIONS: Greater pleomorphism and polymegathism of corneal endothelium was found in patients with severe OSAHS when compared with healthy subjects. Low percentage of REM sleep, usually found in patients with OSAHS, may cause an increase in corneal thickness.

Determinants of continuous positive airway pressure compliance in a group of Greek patients with obstructive sleep apnea.

OBJECTIVE: The aim of the study was to investigate the patients' characteristics that correlate with greater compliance to CPAP use. METHODS: Patients diagnosed with OSAHS and treated with CPAP, who had at least one follow-up visit in the Sleep Clinic during one year, were included in the study. Demographic data, history of symptoms, comorbidities, Body Mass Index (BMI), Epworth Sleepiness Scale questionnaire (ESS), were obtained from patients before and under CPAP use. All variables were correlated with average daily CPAP use. Objective and subjective compliance were estimated and a cut off point of 4.5h/d was used to distinguish 'more compliant' from less 'compliant' patients. RESULTS: Ninety eight patients, with a mean age (+/-SD) of 55.5 (+/-11.1) years were examined. Patients' symptoms improved after CPAP use. The objective compliance was 5.3+/-1.6h/d whereas the subjective compliance was higher. Only 25% of patients were characterized as 'more compliant'. Compliance was positively correlated in a significant way with age and female gender, and negatively correlated with neck circumference, preexisting nasal problems and minimum saturation during sleep. Patients with arterial hypertension showed a trend to better compliance. Weight gain was more frequently observed in 'less compliant' patients. CONCLUSION: To our knowledge this is the first study examining parameters of CPAP compliance in a Greek population of OSAHS patients. Age, gender and minimum saturation during sleep were related to better compliance whereas higher neck circumference and preexisting nasal problems were the parameters related to a worse adherence to treatment.