Automatic Heart Rate Detection during Sleep Using Tracheal Audio Recordings from Wireless Acoustic Sensor.

BACKGROUND: Heart rate is an essential diagnostic parameter indicating a patient's condition. The assessment of heart rate is also a crucial parameter in the diagnostics of various sleep disorders, including sleep apnoea, as well as sleep/wake pattern analysis. It is usually measured using an electrocardiograph (ECG)-a device monitoring the electrical activity of the heart using several electrodes attached to a patient's upper body-or photoplethysmography (PPG). METHODS: The following paper investigates an alternative method for heart rate detection and monitoring that operates on tracheal audio recordings. Datasets for this research were obtained from six participants along with ECG Holter (for validation), as well as from fifty participants undergoing a full night polysomnography testing, during which both heart rate measurements and audio recordings were acquired. RESULTS: The presented method implements a digital filtering and peak detection algorithm applied to audio recordings obtained with a wireless sensor using a contact microphone attached in the suprasternal notch. The system was validated using ECG Holter data, achieving over 92% accuracy. Furthermore, the proposed algorithm was evaluated against whole-night polysomnography-derived HR using Bland-Altman's plots and Pearson's Correlation Coefficient, reaching the average of 0.82 (0.93 maximum) with 0 BPM error tolerance and 0.89 (0.97 maximum) at ±3 BPM. CONCLUSIONS: The results prove that the proposed system serves the purpose of a precise heart rate monitoring tool that can conveniently assess HR during sleep as a part of a home-based sleep disorder diagnostics process.

TGFß carrying exosomes in plasma: potential biomarkers of cancer progression in patients with head and neck squamous cell carcinoma.

OBJECTIVES: Contributions of TGFß to cancer progression are well documented. However, plasma TGFß levels often do not correlate with clinicopathological data. We examine the role of TGFß carried in exosomes isolated from murine and human plasma as a contributor to disease progression in head and neck squamous cell carcinoma (HNSCC). MATERIALS AND METHODS: The 4-nitroquinoline-1-oxide (4-NQO) mouse model was used to study changes in TGFß expression levels during oral carcinogenesis. In human HNSCC, TGFß and Smad3 protein expression levels and TGFB1 gene expression were determined. Soluble TGFß levels were evaluated by ELISA and TGFß bioassays. Exosomes were isolated from plasma using size exclusion chromatography, and TGFß content was quantified using bioassays and bioprinted microarrays. RESULTS: During 4-NQO carcinogenesis, TGFß levels in tumour tissues and in serum increased as the tumour progressed. The TGFß content of circulating exosomes also increased. In HNSCC patients, TGFß, Smad3 and TGFB1 were overexpressed in tumour tissues and correlated with increased soluble TGFß levels. Neither TGFß expression in tumours nor levels of soluble TGFß correlated with clinicopathological data or survival. Only exosome-associated TGFß reflected tumour progression and correlated with tumour size. CONCLUSIONS: Circulating TGFß+ exosomes in the plasma of patients with HNSCC emerge as potential non-invasive biomarkers of disease progression in HNSCC.

Selected ALKBH dioxygenases are overexpressed in salivary gland tumours.

Salivary gland tumours (SGTs) are a heterogeneous group of benign tumours of various origins and pathologies, showing a number of DNA modifications. Previously, in malignant head and neck cancer (HNSCC), we found overexpression of ALKBH proteins, the homologs of Escherichia coli AlkB 2-oxoglutarate and Fe(II) dependent dioxygenase. Moreover, we proved the connection of some of these dioxygenases with cancer development. Here, we studied the expression of five of these ALKBH dioxygenases: 1, 3, 4, 5, and FTO in benign SGTs. Using Western blot analysis, we found overexpression of three proteins: ALKBH1, 4, and FTO in SGT as compared to the surrounding, unaffected tissue. ALKBH4 was overexpressed in 76% of patient samples, whereas ALKBH1 and FTO in 65% of the samples. These results differ from those obtained in HNSCC, where FTO overexpression has been observed in 90% of patient samples. We also investigated the relationships between ALKBHs' expression levels in normal and SGT tissues and identified two correlated pairs: ALKBH1-ALKBH3 and ALKBH1-ALKBH5. Additionally, in tumour tissue ALKBHs: ALKBH1, ALKBH3, ALKBH4, and ALKBH5 levels were correlated with each other. Together, these findings show that the ALKBH proteins exhibit pro cancerogenic action in SGT, even though the levels ALKBHs are generally lower in benign SGT than in malignant HNSCC. We suggest that the overexpression of the ALKBHs, especially FTO, may be used as a cancer marker and for its grading.

Cancer Stem Cell Markers in Rhabdomyosarcoma in Children.

(1) Background: The aim of the present study was to assess the cancer stem cell (CSC) markers CD24, CD44, CD133, and ALDH1A1 in rhabdomyosarcoma (RMS) in children and to define their prognostic role in this group of patients. (2) Methods: The study material was archival tissue specimens collected from 49 patients under 18 years of age and who had been diagnosed with RMS. Immunohistochemistry (IHC) was used to evaluate the expression of the selected CSC markers in the tumor tissue. Expression was evaluated using a semiquantitative IRS scale based on the one developed by Remmele and Stenger and was correlated with the clinical and pathomorphological parameters of prognostic importance in RMS. (3) Results: Expression of the selected CSC markers CD24, CD44, CD133, and ALDH1A1 was demonstrated in 83.7%, 55.1%, 81.6%, and 100% of the RMS patients, respectively. The expression of all of the assessed CSC markers was statistically significantly higher in the study group versus the control group. No significant correlation was found between the expression of the selected CSC markers and clinical and pathological prognostic factors that were analyzed. The expression of the CSC markers did not have a significant influence on RMS survival rates. (4) Conclusions: The results of the conducted study confirm the expression of selected CSC markers in rhabdomyosarcoma tissue in children. The study did not support the prognostic relevance of the expression of any of the assessed CSC markers. However, further studies are needed to fully understand the relevance of the selected CSC markers in RMS carcinogenesis.

Sleep Position Detection with a Wireless Audio-Motion Sensor-A Validation Study.

It is well documented that body position significantly affects breathing indices during sleep in patients with obstructive sleep apnea. They usually worsen while changing from a non-supine to a supine position. Therefore, body position should be an accurately measured and credible parameter in all types of sleep studies. The aim of this study was to specify the accuracy of a neck-based monitoring device (Clebre, Olsztyn, Poland) mounted at the suprasternal notch, in determining a supine and non-supine sleeping position, as well as specific body positions during sleep, in comparison to polysomnography (PSG). A sleep study (PSG along with a neck-based audio-motion sensor) was performed on 89 consecutive patients. The accuracy in determining supine and non-supine positions was 96.9%±3.9% and 97.0%±3.6%, respectively. For lateral positions, the accuracy was 98.6%±2% and 97.4%±4.5% for the right and left side, respectively. The prone position was detected with an accuracy of 97.3%±5.6%. The study showed a high accuracy in detecting supine, as well as other gross positions, during sleep based on a sensor attached to the suprasternal notch, compared to the PSG study. We feel that the suprasternal notch is a promising area for placing wireless sleep study devices.

Supine sleep patterns as a part of phenotyping patients with sleep apnea-a pilot study.

PURPOSE: Polysomnography (PSG) is considered the best objective study to diagnose and quantify sleep disorders. However, PSG involves multiple electrodes and is usually performed in a sleep laboratory that in itself may change the physiology of sleep. One of the parameters that can change during PSG is the sleep position, leading to more supine sleep. The aim of this study was to quantify the amount of supine sleep during PSG and compare it to consecutive nights of a home sleep apnea test (HSAT) in the same patients. METHODS: This prospective study evaluated 22 consecutive patients undergoing PSG followed by HSAT. Sleep position was analyzed during PSG and subsequently on 2 to 6 nights (mean 3.7 nights) at home, and the amount of supine sleep was recorded during each night. RESULTS: Of 22 patients, there were 12 men (55%). The median age was 60.0 years for women and 45.5 years for men. Median proportion of supine sleep during PSG and HSAT was 61% and 26% (p < 0.001), respectively. Four "phenotypes" were identified according to their sleep position during PSG and HSAT, with 5 patients sleeping mainly supine during all nights, 7 patients sleeping mainly non-supine during all nights, 3 patients sleeping in different positions during each night, and 7 patients sleeping supine during PSG but non-supine at home, during HSAT. CONCLUSIONS: There is a higher proportion of supine sleep during PSG compared to home sleep. We identified a subgroup of patients who slept mainly supine during PSG and mainly non-supine during HSAT. PSG may overestimate OSA severity in a specific phenotype of patients.

Epidemiological and clinical characteristics of 407 salivary glands neoplasms in surgically treated patients in 2010-2020.

INTRODUCTION Tumors of the salivary glands account for approximately 3 to 4% of all head and neck neoplasms. It is estimated that 10-15% of them are malignant. The most common benign tumor is pleomorphic adenoma, while the most common malignant tumors are adenoid cystic carcinoma and mucoepidermoid carcinoma. Neoplasms of the salivary glands are extremely histologically diverse, which results from the complex embryogenesis of the salivary glands. The identified risk factors for tumors of the salivary glands are: ultraviolet radiation, ionizing radiation, viral infections, nicotine and alcohol. MATERIAL AND METHOD The aim of the study was an epidemiological analysis of patients with salivary gland neoplasms, the distribution and histopathological characteristics of individual neoplasms treated at the Department of Otorhinolaryngology of the Medical University of Warsaw in 2010-2020. The diagnoses were analyzed according to the latest WHO 2017 histological classification of salivary gland tumors. In addition, the material was supplemented with data on the 5-year survival rates of patients with malignant neoplasms obtained from the Registry of Marital Status. RESULTS AND DISCUSSION The material contained 407 neoplasms of the salivary glands over a 11-year period, of which malignant neoplasms accounted for 17.4%. The malignant tumors were dominated by: adenoid cystic carcinoma (28,2%), mucoepidermoid carcinoma (12,7%), and acinic cell carcinoma (9,9%). Lymphomas (15,5%) were also a large group. The benign neoplasms were dominated by pleomorphic adenoma (54.1%) and Warthin's tumor (36%). Tumors of the salivary gland the most often affected the parotid gland (92%). CONCLUSIONS The obtained data are consistent with the general epidemiological data described in the current literature.

The Role of Chemotherapy in Management of Inoperable, Metastatic and/or Recurrent Melanotic Neuroectodermal Tumor of Infancy-Own Experience and Systematic Review.

Melanotic Neuroectodermal Tumor of Infancy (MNTI) is a very rare pediatric neoplasm of neural crest origin. In most cases, it develops in infants as a localized tumor of the maxilla, and surgery is usually curative. In less than 10% of patients with inoperable, metastatic or persistently recurring MNTI, chemotherapy (CHT) may be considered; however, its role is still unclear. The aim of our study was to assess the efficacy of CHT in children with large, inoperable, metastatic and/or recurrent MNTI. Four such infants, treated with CHT in Polish and German centers of pediatric oncology, were presented. Additionally, a systematic literature search of the PubMed/MEDLINE, Scopus and Web of Science databases was performed, yielding 38 similar cases within the last 42 years. Neoadjuvant CHT, based mainly on the protocols for neuroblastoma, was often effective, allowing for complete delayed surgery in most cases. However, the role of adjuvant CHT in preventing recurrences after incomplete resection of MNTI remains unclear. Disseminated inoperable MNTI was almost universally associated with poor response to CHT and unfavorable outcome. Further investigations to elaborate standards of management in patients with inoperable, metastatic or persistently recurring MNTIs are necessary to improve outcomes.

Elevation of CD40/CD40L Inflammatory Pathway Molecules in Carotid Plaques from Moderate-and-Severe Obstructive Sleep Apnea Patients.

A chronic inflammatory process characteristic of obstructive sleep apnea promotes vascular endothelial dysfunction and atherogenesis. This process can lead to destabilization and rupture of cardiovascular plaques, which clinically manifests as an acute coronary syndrome or stroke. The aim of this study was to investigate the inflammatory pathway leading to plaque destabilization in non-to-mild and moderate-to-severe groups of OSA patients. This prospective study involved enrollment of patients scheduled for endarterectomy. A sleep study was performed prior to surgery. Immunohistochemistry was performed on atherosclerotic plaques from carotid arteries obtained during standard open endarterectomy to determine levels of CD40, CD40L receptors, MCP-1, and MMP-9. The 46 patients included 14 controls, 13 with mild, 11 with moderate, and 8 with severe OSA. Increased expression of CD40, CD40L receptors, MCP-1, and MMP-9 were found to be proportionate with OSA severity. However, significant differences among groups were observed only for MCP-1 (p = 0.014). Increased expression of inflammatory markers (CD40, CD40L, MCP-1, MMP-9) is associated with increasing OSA severity. This suggests the CD40-CD4-L inflammatory pathway may contribute to plaque instability and rupture in OSA patients.

Endoglin Expression and Microvessel Density as Prognostic Factors in Pediatric Rhabdomyosarcoma.

(1) Background: The study proposed to analyze microvessel density (MVD) in rhabdomyosarcoma (RMS) based on the expression of angiogenesis markers and define its prognostic role in this group of patients. (2) Methods: The study included forty-nine pediatric patients diagnosed with RMS. Tumor tissue expression of CD31, CD34, and CD105 was analyzed. MVD was calculated and correlated with clinical RMS prognostic parameters. (3) Results: CD31, CD34, and CD105 are expressed in all RMS cases. MVD/CD105 was significantly higher in the RMS group than in the control group. The mean and median values of MVD/CD105 in RMS were lower than MVD/CD31 and MVD/CD34. MVD/CD105 was significantly higher in patients with alveolar RMS and those with metastatic disease. Patients with higher levels of MVD/CD105 had a higher risk of death (HR = 1.009). (4) Conclusion: CD105 is a relevant angiogenesis marker in pediatric RMS, and MVD/CD105 is an independent risk factor of short overall survival in children with RMS.

The effect of in-lab polysomnography and home sleep polygraphy on sleep position.

PURPOSE: Little is known regarding the influence of in-laboratory polysomnography (PSG) equipment on sleep position, especially on the prevalence of supine positioning, which in many cases may lead to a more severe sleep apnea diagnosis. The aim of this study was to assess the percentage of supine sleep during an in-laboratory PSG compared to that seen during a home sleep apnea test (HSAT). METHODS: This was a retrospective cohort study comparing in-laboratory PSG and HSAT using a peripheral arterial tone (PAT) technology device. RESULTS: Of 445 PSG and 416 HSAT studies analyzed, there was no significant difference in the proportion of supine sleep time between PSG (44%) and HSAT (45%, p = 0.53). Analysis of the differences in sleep position (supine versus non-supine), analyzed by sex, BMI (≥ 30 kg/m2 versus < 30 kg/m2), and age (≥ 60 years versus < 60 years), was significant only for women, who had more supine sleep during HSAT at 61 ± 24% than during PSG at 45 ± 26% (p < 0.001). CONCLUSION: Overall there was no difference in the percentage of supine sleep when comparing in-laboratory PSG to HSAT. However, women had more supine sleep with HSAT than with PSG.

TLRs and RAGE are elevated in carotid plaques from patients with moderate-to-severe obstructive sleep apnea syndrome.

BACKGROUND: There is growing evidence that obstructive sleep apnea (OSA) promotes vascular endothelial dysfunction and atherogenesis. Pathways that mediate this pathology may include Toll-like receptors (TLRs) and receptor for advanced glycation end products (RAGE) which play a significant role in proinflammatory processes. The aim of this study was to measure the expression of the above-mentioned receptors in relation to OSA severity in carotid plaques obtained during open endarterectomy. METHODS: This prospective study included patients with a sleep study prior to surgery and a plaque specimen obtained during standard open endarterectomy. Immunohistochemistry of TLR2, TLR4, TLR7, TLR9, RAGE, HMGB1, and NF-κB was performed on atherosclerotic plaques from carotid arteries of patients with and without OSA. RESULTS: There were 46 patients (22 women, mean age 73.2 ± 1.3 years): 14 control patients, 13 with mild, 11 with moderate, and 8 with severe OSA. The expression of all TLRs and RAGE increased proportionately with increasing OSA severity. The largest differences between patients with severe OSA and no OSA were found for TLR2 (2.88 ± 0.35 vs. 1.27 ± 0.47, p < 0.001), TLR4 (2.88 ± 0.35 vs. 1.64 ± 0.5, p < 0.001), TLR9 (2.38 ± 0.52 vs. 1.45 ± 0.52, p < 0.01), and RAGE (2.5 ± 0.53 vs. 1.82 ± 0.6, p < 0.05). CONCLUSION: TLR2, TLR4, TLR9, and RAGE expression was significantly increased in carotid plaques of patients with moderate-to-severe OSA when compared with control patients with no OSA and those with mild OSA. TLR and RAGE-mediated pathways may play a significant role in OSA-dependent atherogenesis.

ALKBH overexpression in head and neck cancer: potential target for novel anticancer therapy.

The nine identified human homologues of E. coli AlkB 2-oxoglutarate (2OG) and Fe(II)-dependent dioxygenase, ALKBH1-8 and FTO, display different substrate specificities and diverse biological functions. Here we discovered the combined overexpression of members of the ALKBH family in head and neck squamous cell carcinomas (HNSCC). We found direct correlation of ALKBH3 and FTO expression with primary HNSCC tumor size. We observed unidentified thus far cytoplasmic localization of ALKBH2 and 5 in HNSCC, suggesting abnormal role(s) of ALKBH proteins in cancer. Further, high expression of ALKBHs was observed not only in HNSCC, but also in several cancerous cell lines and silencing ALKBH expression in HeLa cancer cells resulted in dramatically decreased survival. Considering the discovered impact of high expression of ALKBH proteins on HNSCC development, we screened for ALKBH blockers among newly synthetized anthraquinone derivatives and demonstrated their potential to support standard anticancer therapy.

Obstructive sleep apnea in patients scheduled for endarterectomy - preliminary study.

Introduction The association between obstructive sleep apnea and atherosclerosis is confirmed for long time, but the pathomechanism is still not known. The aim of this study was to investigate the prevalence of OSA in patients scheduled for endarterectomy and the influence of this procedure on the sleep study parameters and sleepiness. Materials and methods 46 patients scheduled for open carotid endarterectomy were enrolled in the study. Sleep study and Epworth Sleepiness Scale (ESS) was performed preoperatively. In 11 out of 46 patients, sleep study was performed both before and after the surgery. Results The mean age of the group was 69,9 years (± 8,6), 21 patients (45,7%) were female. For 46 patients mean pAHI, ODI, pRDI and %snoring were 16,2 (± SD=15,2), 10,4 (± SD=12,2) and 18,9 (± SD=14,9), respectively. Normal pAHI was noticed in 14 patients (30%), while mild (pAHI 5-15), moderate (pAHI 15-30) and severe (pAHI>30) OSA was observed in 13 (38%), 11 (24%) and 8 (18%) subjects, respectively. The mean ESS score for 27 out of 46 patients was 6,3 (± SD=5,6). The postoperative results of sleep study in 11 patients showed no significant change. Conclusions This study revealed the prevalence of moderate to severe OSA in 42% of patients scheduled for endarterectomy, while no excessive daytime sleepiness was observed in this group. The results of the study show that patients with carotid atherosclerosis should undergo sleep diagnosis in order to rule out obstructive sleep apnea.

RAGE and TLRs as Key Targets for Antiatherosclerotic Therapy.

Receptor for advanced glycation end-products (RAGE) and toll-like receptors (TLRs) are the key factors indicating a danger to the organism. They recognize the microbial origin pathogen-associated molecular patterns (PAMPs) or damage-associated molecular patterns (DAMPs). The primary response induced by PAMPs or DAMPs is inflammation. Excessive stimulation of the innate immune system occurs in arterial wall with the participation of effector cells. Persistent adaptive responses can also cause tissue damage and disease. However, inflammation mediated by the molecules innate responses is an important way in which the adaptive immune system protects us from infection. The specific detection of PAMPs and DAMPs by host receptors drives a cascade of signaling that converges at nuclear factor-κB (NF-κB) and interferon regulatory factors (IRFs) and induces the secretion of proinflammatory cytokines, type I interferon (IFN), and chemokines, which promote direct killing of the pathogen. Therefore, signaling of these receptors' pathways also appear to present new avenue for the modulation of inflammatory responses and to serve as potential novel therapeutic targets for antiatherosclerotic therapy.

Functional identification of abductor and adductor branches for laryngeal transplantation.

PURPOSE: This is a feasibility study of functional identification of the abductor and adductor recurrent laryngeal nerve branches, which could be used in the donor's larynx for functional laryngeal transplantation. METHODS: The study was performed on swine (n = 3) and human (n = 4) models of a donor larynx. The recurrent laryngeal nerve and its branches were found. Using stimulator, abductor and adductor branches were identified, and glottis closing and opening were captured with an endoscope. RESULTS: The result was positive if two ENT specialists noticed at least one adduction and one abduction movement in the same subject. It was obtained in three out of three swine and three out of four humans. CONCLUSIONS: This study shows a way of reinnervation of a transplanted larynx which might result in a functional organ. It describes the first step of the procedure: functional identification of the abductor and adductor branches of the recurrent laryngeal nerve in the donor before the larynx is excised for transplantation.

Prevalence of upper respiratory tract infections in habitually snoring and mouth breathing children.

OBJECTIVES: The aim of the study was to investigate the prevalence of upper respiratory tract infections (URI) - as indicated by rhinosinusitis (RS), ear infections (EI), and antibiotic consumption - in a general pediatric population and evaluate the relationship between these conditions and habitual snoring and mouth breathing during sleep. METHODS: A population-based cross-sectional study was performed in three medium-sized Polish cities from 2011 to 2015. RESULTS: 4837/6963 questionnaires (69.5%) were completed, returned and analyzed. Mean age of studied group was 7.07 ±â€¯0.72 and 7.14 ±â€¯0.73 in girls and boys, respectively. Habitual mouth breathing during sleep (MB) was reported in 907 (18.7%) children and habitual snoring (HS) in 290 (6.0%). 230/290 (79.3%) of children with HS were also MB. Both HS and MB were more prevalent in boys than in girls (p = 0.027 and p < 0.0001, respectively) and neither was associated with BMI (p = 0.11 and p = 0.07, respectively). Habitual snoring and habitual mouth breathing were highly associated with more frequent bouts of rhinosinusitis, ear infections, and antibiotic use (p < 0.0001 for each parameter). CONCLUSIONS: Higher rates of rhinosinusitis, ear infections, and antibiotic consumption were similarly associated with HS and MB. MB is over three times more prevalent in the pediatric population relative to HS, therefore it might be considered as a risk factor for URI and may be included in history of URI.

Association of breathing patterns and quality of life in patients with nasal obstruction.

INTRODUCTION: In the general population, nasal obstruction is a common complaint. However, an objective evaluation of nasal obstruction is difficult. Nose examination, computed tomography (CT), acoustic rhinometry, and anterior rhinomanometry do not accurately reflect the discomfort reported by patients with nasal obstruction. In patients with nasal obstruction, this study evaluated nasal breathing with a unique device for continuous nasal-oral spirometry - a nasal-oral flow analyzer (NOFA); moreover, quality of life was compared between patients with normal nasal breathing on NOFA and of those with impaired nasal breathing on NOFA. METHODS: Of 181 adult patients admitted to an ENT department due to nasal obstruction that were enrolled in the study, 97 (53.6%) completed all per-protocol assessments, including the SF-36 questionnaire and 3-hour, continuous nasal-oral spirometry with NOFA. Based on the presence of normal nasal breathing defined as ≥95% of nasal flow, the 97 patients were divided into those with normal nasal breathing (n=31) and impaired nasal breathing (n=66). RESULTS: Patients with normal nasal breathing differed from those with impaired nasal breathing with respect to all SF-36 subscales (physical functioning, p=0.004; role-physical, p=0.009; bodily pain, p<0.001; general health, p=0.007; vitality, p=0.002; social functioning, p=0.008; mental health, p=0.009; physical component summary, p<0.001; mental component summary, p=0.02), except for the role-emotional subscale (p=0.1). CONCLUSIONS: Among patients with symptoms of nasal obstruction, compared to patients with normal nasal breathing, those with impaired nasal breathing had significantly lower quality of life in the physical and mental domains. Further research needs to determine whether NOFA can be used to diagnose nasal obstruction.

Detecting Breathing and Snoring Episodes Using a Wireless Tracheal Sensor-A Feasibility Study.

OBJECTIVE: Sleep-disordered breathing is both a clinical and a social problem. This implies the need for convenient solutions to simplify screening and diagnosis. The aim of the study was to investigate the sensitivity and specificity of a novel wireless system in detecting breathing and snoring episodes during sleep. METHODS: A wireless acoustic sensor was elaborated and implemented. Segmentation (based on spectral thresholding and heuristics) and classification of all breathing episodes during recording were implemented through a mobile application. The system was evaluated on 1520 manually labeled episodes registered from 40 real-world, whole-night recordings of 16 generally healthy subjects. RESULTS: The differentiation between normal breathing and snoring had 88.8% accuracy. As the system is intended for screening, high specificity of 95% is reported. CONCLUSION: The system is a compromise between nonmedical phone applications and medical sleep studies. The presented approach enables the study to be repetitive, personal, and inexpensive. It has additional value in the form of well-recorded data which are reliable and comparable. SIGNIFICANCE: The system opens unexplored possibilities in sleep monitoring and study enabling a multinight recording strategy involving the collection and analysis of abundant data from thousands of people.