Association of Obstructive Sleep Apnea with Post-Acute Sequelae of SARS-CoV-2 infection (PASC) (preprint)

BackgroundObstructive sleep apnea (OSA) is associated with COVID-19 infection. Fewer investigations have assessed OSA as a possible risk for the development of Post-Acute Sequelae of SARS-CoV-2 infection (PASC). Research QuestionIn a general population, is OSA associated with increased odds of PASC-related symptoms and with an overall definition of PASC? Study DesignCross-sectional survey of a general population of 24,803 U.S. adults. ResultsCOVID-19 infection occurred in 10,324 (41.6%) participants. Prevalence rates for a wide variety of persistent (> 3 months post infection) putative PASC-related physical and mental health symptoms ranged from 6.5% (peripheral edema) to 19.6% (nervous/anxious). In logistic regression models adjusted for demographic, anthropometric, comorbid medical and socioeconomic factors, OSA was associated with all putative PASC-related symptoms with the highest adjusted odds ratios (aOR) being fever (2.053) and nervous/anxious (1.939) respectively. Elastic net regression identified the 13 of 37 symptoms most strongly associated with COVID-19 infection. Four definitions of PASC were developed using these symptoms either weighted equally or proportionally by their regression coefficients. In all 4 logistic regression models using these definitions, OSA was associated with PASC (range of aORs: 1.934-2.071); this association was mitigated in those with treated OSA. In the best fitting overall model requiring [≥]3 symptoms, PASC prevalence was 21.9%. ConclusionIn a general population sample, OSA is associated with the development of PASC-related symptoms and a global definition of PASC. A PASC definition requiring the presence of 3 or more symptoms may be useful in identifying cases and for future research.

Nonalcoholic fatty liver disease and non-liver comorbidities.

Non-alcoholic fatty liver disease (NAFLD) is a chronic liver disease characterized by excess fat accumulation in the liver. It is closely associated with metabolic syndrome, and patients with NAFLD often have comorbidities such as obesity, type 2 diabetes mellitus, and dyslipidemia. In addition to liver-related complications, NAFLD has been associated with a range of non-liver comorbidities, including cardiovascular disease, chronic kidney disease, and sleep apnea. Cardiovascular disease is the most common cause of mortality in patients with NAFLD, and patients with NAFLD have a higher risk of developing cardiovascular disease than the general population. Chronic kidney disease is also more common in patients with NAFLD, and the severity of NAFLD is associated with a higher risk of developing chronic kidney disease. Sleep apnea, a disorder characterized by breathing interruptions during sleep, is also more common in patients with NAFLD and is associated with the severity of NAFLD. The presence of non-liver comorbidities in patients with NAFLD has important implications for the management of this disease. Treatment of comorbidities such as obesity, type 2 diabetes mellitus, and dyslipidemia may improve liver-related outcomes in patients with NAFLD. Moreover, treatment of non-liver comorbidities may also improve overall health outcomes in patients with NAFLD. Therefore, clinicians should be aware of the potential for non-liver comorbidities in patients with NAFLD and should consider the management of these comorbidities as part of the overall management of this disease.

ERS technical standards for using type III devices (limited channel studies) in the diagnosis of sleep disordered breathing in adults and children.

For more than three decades, type III devices have been used in the diagnosis of sleep disordered breathing in supervised as well as unsupervised settings. They have satisfactory positive and negative predictive values for detecting obstructive and central sleep apnoea in populations with moderately high pre-test probability of symptoms associated with these events. However, standardisation of commercially available type III devices has never been undertaken and the technical specifications can vary widely. None have been subjected to the same rigorous processes as most other diagnostic modalities in the medical field. Although type III devices do not include acquisition of electroencephalographic signals overnight, the minimum number of physical sensors required to allow for respiratory event scoring using standards outlined by the American Academy of Sleep Medicine remains debatable. This technical standard summarises data on type III studies published since 2007 from multiple perspectives in both adult and paediatric sleep practice. Most importantly, it aims to provide a framework for considering current type III device limitations in the diagnosis of sleep disordered breathing while raising research- and practice-related questions aimed at improving our use of these devices in the present and future.

Obstructive sleep apnea: a major risk factor for COVID-19 encephalopathy? (preprint)

Background This study evaluates the impact of comorbid obstructive sleep apnea (OSA) on coronavirus disease 2019 (COVID-19) acute encephalopathy (AE). Methods Between 3/1/2020 and 11/1/2021, 97 consecutive patients were evaluated at the Geneva University Hospitals with a neurological diagnosis of COVID-19 AE. They were divided in two groups depending on the presence or absence of high risk for OSA based on the modified NOSAS score (mNOSAS, respectively ≥8 and <8). We compared patients’ characteristics (clinical, biological, brain MRI, EEG, pulmonary CT). The severity of COVID-19 AE relied on the RASS and CAM scores. Results Most COVID-19 AE patients presented with a high mNOSAS, suggesting an underlying OSA (>80%). Patients with a high mNOSAS had a more severe form of COVID-19 AE (84.8% versus 27.8%), longer mean duration of COVID-19 AE (27.9 versus 16.9 days), higher mRS at discharge (≥3 in 58.2% versus 16.7%), and increased prevalence of brain vessels enhancement (98.1% versus 20.0%). Underlying OSA was associated with a 14 fold increased risk of developing a severe COVID-19 AE (OR=14.52). Discussion These observations suggest an association between comorbid OSA and COVID-19 AE severity. Comorbid OSA could be a predisposing factor leading to severe COVID-19 AE and consecutive long-term sequalae.

Sleep testing during the pandemic.

BACKGROUND: The COVID-19 pandemic disrupted the U.S. healthcare system, reducing the capacity available for unrelated conditions, such as sleep disordered breathing, and increasing concerns about the safety of in-lab testing. This study characterizes how the pandemic impacted the assessment of sleep disordered breathing and use of associated services. METHODS: Sleep testing claims occurring between January 2019 and June 2021 were extracted from the database of a national healthcare organization. Utilization was trended. Logistic regressions were run to assess the association between quarter of initial testing, whether testing was followed by treatment, and whether testing was followed by a clinical visit with a diagnosis related to sleep apnea, after controlling for patient-related factors. A Cox proportional hazards model assessed factors influencing time to treatment. Finally, a logistic regression assessed factors influencing the finality of home-based testing. RESULTS: In Q2 2021, home-based testing utilization was 134% of its initial level, while in-lab and split night testing were both at 61% of initial levels. Patients receiving initial home-based testing did not significantly differ in their likelihood of treatment, but were significantly less likely to have a clinical visit for sleep apnea (P < 0.01). Patients initially tested in 2021 were treated significantly more quickly than those initially tested in Q1 2019. Home-based testing occurring in Q4 2019 or later was significantly more likely to be definitive than home-based testing occurring Q1 2019. CONCLUSIONS: Home-based sleep testing increased significantly and durably in 2020, and was associated with faster time to treatment than initial in-lab testing.

Mortality Patterns among COVID-19 Patients in Two Saudi Hospitals: Demographics, Etiology, and Treatment (preprint)

Background: Saudi Arabia (SA) reported its first case of COVID-19 on 2 March 2020. Mortality varied nationwide: by 14 April 2020 Medina had 16% of SA’s total COVID-19 cases and 40% of all COVID-19 deaths. A team of epidemiologists investigated to identify factors impacting survival. Methods: We reviewed medical records from two hospitals: Hospital A in Medina and Hospital B in Dammam. All patients with a registered COVID-related death between 1 March -22 April 2020 were included. We collected data on demographics, chronic health conditions, clinical presentation and treatment. We analysed data using SPSS. Results: We identified 76 cases: 38 cases from each hospital. More fatalities were among non-Saudis at Hospital A (89%) versus Hospital B (82%, p<.001). Hypertension prevalence was higher among cases at Hospital A (42%) versus Hospital B (21%) (p<.05). We found statistically significant differences (p<.05) in symptoms at initial presentation among cases at Hospital A versus Hospital B, including: body temperature (38º C vs 37º C), heart rate (104 bpm vs 89 bpm), and regular breathing rhythms (61% vs 55%). Less cases (50%) at Hospital A received heparin versus Hospital B (97%, p-value< 0.001). Conclusion: Patients who died at Hospital A typically presented with more severe illness and were more likely to have underlying health conditions. Migrant workers may be at increased risk due to poorer baseline health and reluctance to seek care. This highlights the importance of cross-cultural outreach to prevent deaths. Health education efforts should be multilingual and accommodate all literacy levels.

The Utility of Home Sleep Apnea Testing in the Advanced Heart Failure Populations.

Untreated sleep disorders form a risk of coronary artery disease, hypertension, obesity, and diabetes mellitus. Access to polysomnography is limited, especially during the COVID-19 pandemic, with home sleep apnea testing (HSAT) being a potentially viable alternative. We describe an HSAT protocol in patients with advanced heart failure (HF). In a single-center, observational analysis between 2019 and 2021 in patients with advanced HF and heart transplant (HT), 135 screened positive on the STOP-Bang sleep survey and underwent a validated HSAT (WatchPAT, ZOLL-Itamar). HSAT was successful in 123 patients (97.6%), of whom 112 (91.1%; 84 HF and 28 HT) tested positive for sleep apnea. A total of 91% of sleep apnea cases were obstructive, and 63% were moderate to severe. Multivariable linear regression showed that the apnea hypopnea index was 34% lower in the HT group than in the HF group (p = 0.046) after adjusting for gender, and that this effect persisted in White patients but not among African-Americans. Patient characteristics were similar between groups, with coronary artery disease, diabetes mellitus, and hypertension as the most prevalent co-morbidities. In conclusion, sleep apnea remains prevalent in patients with HF with a high co-morbidity burden. HSAT is a feasible and effective tool for screening and diagnosis in this population.

Influences of sleep and lifestyle factors on the risk for covid-19 infections, from internet survey of 10,000 Japanese business workers.

We conducted an internet survey to assess sociodemographic variables, lifestyle factors, sleep problems, and comorbidities for sleep apnea syndrome (SAS) in COVID-19 and influenza (FLU) infections. Data from 10,323 workers (50.0% male) were analyzed. COVID-19 was diagnosed in 144 subjects (COVID-19+), and 8,693 were classified as not suspected to be infected (COVID-19-). SAS had been diagnosed in 35.4% of the COVID-19+ subjects, but only 231 (2.7%) of the 8,693 COVID-19- subjects. COVID-19+ subjects were more susceptible to FLU (35.4%) compared to COVID-19- subjects (3.0%). A multivariate analysis revealed that higher risks of COVID-19+ were linked to the following factors: going out without a face mask (OR 7.05, 95% CI 4.53-11.00), FLU+ (OR 6.33, 95% CI 3.80-10.54), excessive exercise before going to sleep (OR 2.10, 95% CI 1.63-2.70), SAS+ (OR 5.08, 95% CI 2.88-8.94), younger age (OR 1.05, 95% CI 1.03-1.07), falling sleep while sitting or talking with someone (OR 3.70, 95% CI 2.30-5.95), and use of hypnotics (OR 2.28, 95% CI 1.20-4.30). Since sleep impairment played a relatively small role in COVID-19+/SAS- subjects, we assume that SAS itself was a more significant risk factor for COVID-19 infection rather than sleep impairment. A better understanding of the mechanisms that result in increased susceptibility to COVID-19 in SAS is vital for helping prevent COVID-19.

Obstructive Sleep Apnea with COVID-19.

The novel coronavirus disease-2019 (COVID-19) and the ensuing pandemic have greatly impacted the global healthcare system due to its high infectiousness, associated high mortality, and a complete lack of immunity in the population. Globally, the COVID-19 pandemic has unleashed a health crisis that has not only seriously disrupted people's lives but also affected their normal sleep, along with physical and mental health; this situation is especially exacerbated in people suffering from pre-existing conditions, such as sleep apnea. A recent meta-analysis of 18 studies by Miller et al. (September 2020) showed that obstructive sleep apnea (OSA) is related to higher mortality and morbidity in patients with COVID-19 and is most likely independent of other risk factors. A recent meta-analysis indicated that COVID-19 patients with OSA are more severely affected than those without OSA, thereby providing further evidence that concurrent OSA may elevate the severity of COVID-19 infection, along with the risk of mortality. The COVID-19 pandemic has significantly impacted the diagnosis and therapeutic management of patients with OSA. Thus, it is necessary to identify and develop new diagnostic and therapeutic avenues in the future. In this context, the current study summarizes known associations between COVID-19 and OSA and the regular diagnostic and therapeutic strategies for OSA in the light of COVID-19 pandemic prevention and control.

Prevalence of sleep apnea in children and adolescents in Colombia according to the national health registry 2017-2021.

OBJECTIVE: To describe the sociodemographic and epidemiological characteristics of diagnosis and treatment of pediatric patients with sleep apnea, both central and obstructive, in Colombia between 2017 and 2021. METHODS: Observational, descriptive, cross-sectional, epidemiological study using the International Classification of Diseases and Related Health Problems as search terms for sleep apnea, based on SISPRO, the Colombian national health registry. Stratification by gender and age groups was performed. We also generated data of the amount of diagnostic and therapeutic procedures performed. A map of prevalence by place of residency was performed. RESULTS: National records report 15200 cases of SA between 2017 and 2021, for an estimated prevalence of 21.1 cases by 100000 inhabitants in 2019 the year with the most cases (4769), being more frequent and in the 6 to 11 age group and in males, with a male to female ratio of 1.54:1. The number of cases declined in 2020 and 2021. The map showed a concentration of cases in the more developed departments of the country. DISCUSSION: This is the first approximation to a nation-wide prevalence of sleep apnea in Colombia which is lower to what is found in the literature worldwide, including studies performed in Latin America and in Colombia, this could reflect sub diagnosis and sub report. The fact that the highest prevalence was found in males and in the 6-11 age group is consistent with reports in literature. The decrease in cases in 2020 and 2021 could be related to the COVID-19 pandemic impact in sleep medicine services.

Nasal and Parotid Blood Pool Activity Is Significantly Correlated with Metabolic Syndrome Components and Sleep Apnea.

Background: Patients with metabolic syndrome components were frequently noted to have increased nasal and parotid activity on clinically referred scintigraphic whole-body blood pool scans. This increase in activity was not observed in patients without metabolic syndrome. Increased nasal blood pool activity in patients with elevated body mass indices (BMIs) has implications for (1) sleep apnea, (2) risk of nasal infection, and (3) possible impaired nasal lymphatic drainage of brain waste proteins. Methods: To follow-up this clinical observation, a retrospective study was performed on 200 patients having whole-body blood pool scans referred over a 3-year period. The whole-body blood pool scans were evaluated for an association between nose and parotid region of interest (ROI) to heart ROI maximum (max) pixel ratios as correlated with clinical conditions, including obesity, diabetes, hypertension, and sleep apnea. Continuous variables of BMI, hemoglobin A1c (HbA1c), blood glucose, and blood lipids were also correlated with these ratios. Results: A direct association of nose to heart max ratio (NHMR) with diabetes, sleep apnea, and hypertension was found with an increase in the ratio of +0.10 (P = 0.002), +0.13 (P = 0.0002), +0.08 (P = 0.0123), respectively. Correlation of NHMR with continuous variables had moderate correlation with BMI (r = 0.36, P < 0.0001), glucose (r = 0.27, P = 0.0001), HbA1c (r = 0.25, P = 0.0008) and less association with the number of diabetes medications (r = 0.22, P = 0.0021). Similar associations were found for parotid to heart max ratios but were weaker than the NHMR. Conclusions: Patients with metabolic syndrome components have significantly increased nasal and parotid activity on blood pool scans. These associations have implications for the treatment of sleep apnea, for nasal infections involving such agents as Covid-19, and for the risk of dementias related to decreased clearance of brain waste proteins through nasal turbinate lymphatics in patients with metabolic syndrome. If further studies support these findings, the nasal turbinates and the increased parasympathetic activity controlling their dilation could become a new therapeutic target.

Restless legs syndrome is associated with long-COVID in women.

STUDY OBJECTIVES: Sleep disturbance is common in long-COVID (LC). Restless legs syndrome (RLS) is characterized by sleep disturbance and has been reported after viral infections. Therefore, we evaluated RLS symptoms cross-sectionally in individuals with LC at both current and pre-coronavirus disease 2019 (pre-COVID-19) time points. METHODS: Adults on LC-focused Facebook pages were recruited for an online assessment of symptoms before COVID-19 infection and during their present LC state in a cross-sectional manner. The LC group documented baseline symptoms retrospectively. Questions were included about the presence/severity of RLS symptoms and assessments of fatigue, quality of life, and sleep apnea. A control group was recruited and included individuals ≥ 18 years of age who never had overt symptoms of COVID-19. Pregnancy was an exclusion criterion for both groups. RESULTS: There were 136 participants with LC (89.7% females, age 46.9 ± 12.9 years) and 136 controls (65.4% females, age 49.2 ± 15.5). RLS prevalence in females with LC was 5.7% pre-COVID-19 and 14.8% post-COVID-19 (P < .01) vs 6.7% in control females. Severity of RLS was moderate in both groups. Logistic regression predicting post-COVID-19 RLS among females with LC failed to find significant effects of hospitalization, sleep apnea, neuropathic pain severity, or use of antihistamines and antidepressants. CONCLUSIONS: The baseline prevalence of RLS in females with LC was similar to the general population group as well as to patients in epidemiological studies. The prevalence significantly increased in the LC state. Postinfectious immunological mechanisms may be at play in the production for RLS symptoms. CITATION: Weinstock LB, Brook JB, Walters AS, Goris A, Afrin LB, Molderings GJ. Restless legs syndrome is associated with long-COVID in women. J Clin Sleep Med. 2022;18(5):1413-1418.

Sleep health and the circadian rest-activity pattern four months after COVID-19.

OBJECTIVE: To describe the prevalence and severity of sleep disorders and circadian alterations in COVID-19 patients four months after the acute phase of the disease. METHODS: This was a cross-sectional observational prospective study of patients with mild COVID-19, moderate COVID-19 (requiring hospitalization but no mechanical ventilation), or severe COVID-19 (with ARDS) four months after the acute phase of the disease. All patients underwent a home sleep apnea test and seven-day wrist actigraphy, as well as completing questionnaires to assess sleep quality and mental health. Differences among the three groups of patients were evaluated by ANOVA and the chi-square test. RESULTS: A total of 60 patients were included in the study. Of those, 17 were in the mild COVID-19 group, 18 were in the moderate COVID-19 group, and 25 were in the severe COVID-19 group. Sleep quality, as assessed by satisfaction, alertness, timing, efficiency, and duration scale scores, was found to be impaired in all three groups, which also had a high prevalence of unhealthy sleep, as assessed by the Pittsburgh Sleep Quality Index. The prevalence of insomnia was increased in all three groups, as assessed by the Insomnia Severity Index. The home sleep apnea test showed that the overall prevalence of obstructive sleep apnea was 60%, and seven-day wrist actigraphy showed that total sleep time was < 7 h in all three groups. Changes in quality of life and in the circadian rest-activity pattern were observed in all three groups. CONCLUSIONS: Sleep-related symptoms, changes in the circadian rest-activity pattern, and impaired mental health appear to be common in COVID-19 patients four months after the acute phase of the disease, severe COVID-19 being associated with a higher prevalence of obstructive sleep apnea.

Prognostic factors for mortality, ICU and hospital admission due to SARS-CoV-2: A systematic review and meta-analysis of cohort studies in Europe (preprint)

BackgroundAs mortality from COVID-19 is strongly age-dependent, we aimed to identify population subgroups at an elevated risk for adverse outcomes from COVID-19 using age/gender-adjusted data from European cohort studies with the aim to identify populations that could potentially benefit from booster vaccinations. MethodsWe performed a systematic literature review and meta-analysis to investigate the role of underlying medical conditions as prognostic factors for adverse outcomes due to SARS-CoV-2, including death, hospitalisation, Intensive Care Unit (ICU) admission, and mechanical ventilation within three separate settings (community, hospital and ICU). Cohort studies that reported at least age and gender-adjusted data from Europe were identified through a search of peer-reviewed articles published until 11th June 2021 in Ovid Medline and Embase. Results are presented as Odds Ratios (ORs) with 95% confidence intervals (95%C.I.) and absolute risk differences (RD) in deaths per 1,000 COVID-19 patients. FindingsWe included 88 cohort studies with age/gender adjusted data from 6,653,207 SARS-CoV-2 patients from Europe. Hospital-based mortality was associated with high and moderate certainty evidence for solid organ tumours, diabetes mellitus, renal disease, arrhythmia, ischemic heart disease, liver disease, and obesity, while a higher risk, albeit with low certainty, was noted for chronic obstructive pulmonary disease and heart failure. Community-based mortality was associated with a history of heart failure, stroke, diabetes, and end-stage renal disease. Evidence of high/moderate certainty revealed a strong association between hospitalisation for COVID-19 and solid organ transplant recipients, sleep apnoea, diabetes, stroke, and liver disease. InterpretationThe results confirmed the strong association between specific prognostic factors and mortality and hospital admission. Prioritisation of booster vaccinations and the implementation of non-pharmaceutical protective measures for these populations may contribute to a reduction in COVID-19 mortality, ICU and hospital admissions. FundingEuropean Centre for Disease Prevention and Control (ECDC) under specific contract No. 10 ECD.11843 within Framework contract ECDC/2019/001 Lot 1B.

Did COVID-19 impact Positive Airway Pressure adherence in 2020? A cross-sectional study of 8477 patients with sleep apnea.

BACKGROUND: Whether the COVID-19 pandemic impacts Positive Airway Pressure (PAP) adherence over the long-term is unknown and only preliminary short-term data have been reported. METHODS: With the aim of describing the impact of the first and second waves of COVID-19 on PAP adherence during 2020 in France, we designed a cross-sectional study of Sleep-Apnea (SA)-patients under PAP telemonitoring. To examine PAP adherence in adult SA patients, we assessed de-identified data from a non-profit healthcare provider database during the period January 1, 2019 to December 31, 2020. Included patients met the following criteria: (i) PAP-treated for at least 4 months before January 1, 2019 and with continuous PAP during both 2019 and 2020; (ii) ≥ 360 daily PAP telemonitored data per year. For PAP adherence, data were collected using the PAP-software. RESULTS: 8477/10482 patients were finally included in the analysis [72.4% male, median age 70 years (IQ25-75: 61-77], 25.6% < 62 years old, initial Apnea-Hypopnea Index (AHI) of 41 (31-59)/h. Median PAP adherence was 7.21 (6.12-8.10) h/day in 2020 versus 7.12 (6.05-8.02) h/day in 2019, p < 0.001. The median difference in PAP adherence between the first 2020 lockdown and the corresponding 2019 weeks was 9.75 (CI95% 8.75-10.75) min/day, p < 0.001. The median difference in PAP adherence between the second 2020 lockdown and the corresponding 2019 weeks was 5.00 (CI95% 4.00-6.00) min/day, p < 0.001. If we consider the minimal clinically important difference of 30 min for PAP adherence, 30.4% and 26% of the patients increased their PAP adherence by at least 30 min during the first and second lockdowns respectively; 17.6% and 19.3% of the patients lowered their PAP adherence by at least 30 min in the first and second lockdowns, respectively. CONCLUSION: During the first and second lockdowns, the COVID-19 pandemic had a clinically irrelevant effect on PAP adherence for the study population. Future studies are needed to describe COVID-19 pandemic impact on PAP adherence not only for long-term PAP-treated SA patients but also for incident cases. Trial registration The COVADENE study was registered on March 1st, 2021 on ClinicalTrials.gov (Identifier: NCT04775966).

The oxygenation module: the missing link in using sleep apnea devices to treat COVID-19 pneumonia at home.

BACKGROUND: The study aims at solving the problem with the limitations of the homecare CPAP equipment such as sleep apnea devices in the treatment of COVID-19 pneumonia. By adding an advanced, rapid-to-produce oxygenation module to existing CPAP devices we allow distributing healthcare at all levels, reducing the load on intensive care units, promoting treatment in the early stages at homecare. A significant part of the COVID-19 pneumonia patients requires not only an oxygen supply but also additional air pressure. Existing home care devices are able to create precise positive airway pressure, but cannot precisely measure supplied oxygen concentration. Either uses uncertified and potentially unsafe mechanisms. RESULTS: The developed system allows using certified and widely available CPAP (constant positive airway pressure) devices to perform the critical function of delivering pressure and oxygen to airways. CPAP device is connected to the designed add-on module that can provide predefined oxygen concentration in a precise and stable manner. Clinical test results include data from 12 COVID-19 positive patients. The device has been compared against certified NIV (non-invasive) equipment under 6-20 hPa pressure and 30-70% FiO2. Tests have proved that the developed system can achieve the same SaO2 (p = 0.93) and PaO2 (p = 0.80) levels as NIV with clinically insignificant differences. Test results show that the designed system can substitute NIV equipment for a significant part of COVID-19 patients while leaving existing NIV devices for unstable and critical patients. The system has been designed to be mass-produced while having medically certified critical components. CONCLUSION: The clinical testing of the new device for oxygen supplementation of patients treated using simple CPAP devices looks promising and could be used for the treatment of COVID-19 pneumonia.

A Novel Portable Real-Time Low-Cost Sleep Apnea Monitoring System based on the Global System for Mobile Communications (GSM) Network.

BACKGROUND AND OBJECTIVE: Continuous monitoring of breathing activity plays a vital role in the detection of respiratory-based diseases (SA, COPD, etc.). Sleep Apnea (SA) is characterized by recurrent upper airway obstruction during sleep associated with arterial blood desaturation, sympathetic nervous system activation, and cardiovascular impairment. Untreated patients with SA have increased mortality rates compared to the general population. This study aims to design a remote monitoring system for sleep apnea to ensure patient safety and ease the workload of doctors in the Covid-19 era. METHODS: This study aims to design a remote monitoring system for sleep apnea to ensure patient safety and ease the workload of doctors. Our study focuses on a novel portable real-time low-cost sleep apnea monitoring system utilizing the GSM network (GSM Shield Sim900a). Proposed system is a remote monitoring and patient tracking system to detect the apnea event in real time, and to provide information of the sleep position, pulse, and respiratory and oxygen saturation to the medical specialists (SpO2) by establishing a direct contact. As soon as an abnormal condition is detected in the light of these parameters, the condition is reported (instant or in the form of short reports after sleep) to the patient relatives, the doctor's mobile telephone or to the emergency medical centers (EMCs) through a GSM network to handle the case depending on the patient's emergency condition. RESULTS: A study group was formed of six patients for monitoring apnea events (three males and three females) between the ages of 20 and 60. The patients in the study group have sleep apnea (SA) in different grades. All the apnea events were detected, and all the patients were successfully alerted. Also, the patient parameters were successfully sent to all patient relatives. Patients who could not get out of apnea were called through the CALL feature, and they were informed about their ongoing apnea event and told that intervention was necessary. The proposed system is tested on six patients. The beginning moment of apnea was successfully detected and the SMS/CALL feature was successfully activated without delay. During the testing, it has been observed that while some of the patients start breathing after the first SMS, some others needed the second or the third SMS. According to the measurement result, the maximum breathless time is 46 s among the patients, and a SMS is sent every 15 s. In addition, in cases where the patient was breathless for a long time, the CALL feature was actively sought from the relatives of the patient and enabled him to intervene. The proposed monitoring system could be used in both clinical and home settings. CONCLUSIONS: The monitoring of a patient in real time allows to intervene in any unexpected circumstances about the patient. The proposed work uses an acceleration sensor as a reliable method of the sleep apnea for monitoring and prevention. The developed device is more economical, comfortable, and convenient than existing systems not only for the patients but also for the doctors. The patients can easily use this device in their home environment, so which could yield a more comfortable, easy to use, cost-effective, and long-term breathing monitoring system for healthcare applications.