Undiagnosed Obstructive Sleep Apnea and Acute COVID-19 Infection—A Case Series

A recently published study on coronavirus disease 2019 (COVID-19) and obstructive sleep apnea (OSA) suggested that there might be an association between certain risk factors and comorbidities associated with OSA, which are also associated with poor COVID-19 outcomes. However, it is unclear whether undiagnosed OSA correlates with COVID-19 severity in a South Korean population. We identified 7 patients who presented with nocturnal hypoxemia during hospitalization due to COVID-19. All patients underwent polysomnography 5–9 weeks after the infection. We retrospectively collected the patients’ baseline characteristics, hospital admission data, and polysomnography findings. Of the 7 patients, all were diagnosed with OSA after COVID-19 infection. Their mean (±SD) age was 45.4±16.3 years, 57.1% were men, and their mean (±SD) body mass index was 33.4±6.0 kg/m2. Six patients presented with COVID-19-related pneumonia on chest X-rays, 3 of whom were admitted to the intensive care unit during the acute phase. The overnight polysomnography showed a mean AHI of 59.0±38.5/h and an oxygen desaturation index of 57.6±39.7/h. Undiagnosed OSA is a prevalent condition associated with moderate to severe COVID-19 infection. The study patients with sleep apnea and COVID-19 had obesity and severe oxygen desaturation but did not complain of daytime sleepiness.

Feasibility of the modified 30-second sit-to-stand test in an isolation ward of moderate COVID-19

BACKGROUND The recovery after prolonged immobilization during hospitalization because of COVID-19 is the primary goal of moderate to severe COVID-19 rehabilitation. Lower extremity muscle function assessment after immobilization is needed before starting mobilization. Hence, this study aimed to evaluate the feasibility of the modified 30-second sit-to-stand test (m30STS) as one of the prospective tools of functional capacity assessment in moderate COVID-19. METHODS This cross-sectional study recruited the subjects consecutively. All eligible subjects with oxygen saturation (SaO2) ≥95% with or without oxygen supplementation performed the m30STS following the Bohannon’s guidelines. The score of m30STS was calculated based on the number of stands completed within 30 sec. A higher score of the m30STS indicated better lower extremity function. RESULTS Mean score of m30STS was 13.3. No subjects had oxygen desaturation or increased heart rate, and no fall incidents occurred. CONCLUSIONS The m30STS is feasible and safe to evaluate lower extremity for moderate COVID-19 patients with SaO2 >95%. The absence of oxygen desaturation and increase in heart rate showed no increased oxygen consumption during the test.

Potential Mechanisms Underlying Hypoxia-Induced Diabetes in a Rodent Model: Implications for COVID-19

Previous studies reported that repetitive hypoxia in rat pups reduces insulin secretion and elevates fasting blood glucose levels; these sequelae persisted for several months. This report describes how episodic hypoxic events elevate a chloride ion exporter, K+-Cl− cotransporter-2 (KCC2), in the plasma membrane of insulin-secreting pancreatic β-cells. We assume that acute diabetic symptoms observed in rat pups with periodic oxygen desaturation could result from a lack of blood insulin levels due to disturbed β-cell function. This acute hypo-insulinemia may result from a disruption in chloride balance in β-cells arising from an imbalanced KCC2-NKCC1 (chloride exporter-importer) density as a consequence of periodic oxygen desaturation. Mechanistically, we postulate that a reduced insulin secretion due to the KCC2-NKCC1 imbalance subsequent to acute oxygen desaturation could result in hyperglycemia in rat pups, paralleling symptoms shown in patients with COVID-19 who experienced acute respiratory distress.

Validation of a Wrist-Worn Reflectance Pulse Oximeter During Sleep and Prediction of Obstructive Sleep Apnea: A Proof-of-Concept Study (Preprint)

BACKGROUND Obstructive sleep apnea (OSA) is a common sleep disorder characterized by repetitive upper airway obstruction during sleep, thereby resulting in oxygen desaturation, frequent arousals, and increased sympathetic activity. Wearable devices that measure peripheral oxygen saturation have been developed for the screening of OSA. OBJECTIVE This study aimed to validate and characterize the estimation function of oxygen saturation measured by wrist-worn reflectance pulse oximetry during sleep and to predict the derived OSA using the oxygen desaturation index (ODI). METHODS Oxygen saturation was simultaneously measured using reflectance pulse oximetry from the Samsung Galaxy Watch 4 series (SM-R890N, SM-R860N, Samsung Electronics Co.; GW4) and transmittance pulse oximetry from polysomnography as a reference (SpO2Ref). The performance was evaluated by the root mean squared error (RMSE) and coverage rate, and it was compared according to the apnea-hypopnea index (AHI). The GW4-ODI was used to predict moderate to severe OSA. RESULTS A total of 97 adults (44.4 ± 13.0 years; men 76.3%, women 23.7%) participated in this study. Depending on the AHI, participants were classified as either normal (n=18), mild (n=21), moderate (n=23), or severe OSA (n=35). Wrist-worn reflectance pulse oximetry showed an overall RMSE of 2.3% and negligible bias of -0.2%. A Bland-Altman density plot showed good agreement of oxygen saturation between GW4 and the reference pulse oximeter. RMSEs were 1.65 ± 0.57%, 1.76 ± 0.65%, 1.93 ± 0.54%, and 2.93 ± 1.71% for normal, mild, moderate, and severe OSA, respectively. GW4-ODI ≥5/h had the highest predictive ability for moderate to severe OSA with a sensitivity of 89.7%, a specificity of 64.1%, an accuracy of 79.4%, and an area under the curve of 0.908 (95% CI, 0.852–0.963). CONCLUSIONS GW4 was successfully validated for measuring oxygen saturation with reflectance pulse oximetry during sleep. This study demonstrates the feasibility of GW4 for screening moderate to severe OSA.

Association and Risk Factors for Obstructive Sleep Apnea and Cardiovascular Diseases: A Systematic Review

Obstructive sleep apnea (OSA) is a serious, potentially life-threatening condition. Epidemiologic studies show that sleep apnea increases cardiovascular diseases risk factors including hypertension, obesity, and diabetes mellitus. OSA is also responsible for serious illnesses such as congestive heart failure, stroke, arrhythmias, and bronchial asthma. The aim of this systematic review is to evaluate evidence for the association between OSA and cardiovascular disease morbidities and identify risk factors for the conditions. In a review of 34 studies conducted in 28 countries with a sample of 37,599 people, several comorbidities were identified in patients with severe OSA—these were: heart disease, stroke, kidney disease, asthma, COPD, acute heart failure, chronic heart failure, hyperlipidemia, thyroid disease, cerebral infarct or embolism, myocardial infarction, and psychological comorbidities including stress and depression. Important risk factors contributing to OSA included: age > 35 years; BMI ≥ 25 kg/m2; alcoholism; higher Epworth sleepiness scale (ESS); mean apnea duration; oxygen desaturation index (ODI); and nocturnal oxygen desaturation (NOD). Severe OSA (AHI ≥ 30) was significantly associated with excessive daytime sleepiness and oxygen desaturation index. The risk of OSA and associated disease morbidities can be reduced by controlling overweight/obesity, alcoholism, smoking, hypertension, diabetes mellitus, and hyperlipidemia.

79 Platypnea–orthodeoxia syndrome as an uncommon cause of dyspnoea in a nonagenarian with aortic dissection

Methods and results Platypnea–Orthodeoxia syndrome (POS) is an uncommon but challenging clinical condition characterized by positional dyspnoea (platypnea) and arterial desaturation (orthodeoxia) in the upright position that improve in the supine position. POS can occur insidiously, as progressive unexplained oxygen desaturation for months or years, or as acute life-threatening unexplained hypoxaemia. The most common cause is the presence of an intracardiac shunt (patent foramen ovale and other interatrial defects) associated with a secondary anatomic or functional defect that serve as substrate for a right to left intracardiac shunt leading to oxygen desaturation. Conclusions Herein we present the case of a nonagenarian with a known history of ascending aortic aneurysm, that was admitted to the emergency department of our institution with a complaint of intermittent chest pain and dyspnoea. POS was then diagnosed, and the patient underwent a successful percutaneous closure with an Amplatzer™ device (25/25 mm) with minimal residual right-to-left shunt leading to a significant relief of the dyspnoea and improvement of arterial saturation. We also herein revise the clinical presentation, pathophysiology, diagnostic work-up, and management of patients with POS, aiming at increasing the awareness of this uncommon but often misdiagnosed treatable condition.

Accuracy and usability of AcuPebble SA100 for automated diagnosis of obstructive sleep apnoea in the home environment setting: an evaluation study

ObjectivesObstructive sleep apnoea (OSA) is a heavily underdiagnosed condition, which can lead to significant multimorbidity. Underdiagnosis is often secondary to limitations in existing diagnostic methods. We conducted a diagnostic accuracy and usability study, to evaluate the efficacy of a novel, low-cost, small, wearable medical device, AcuPebble_SA100, for automated diagnosis of OSA in the home environment.SettingsPatients were recruited to a standard OSA diagnostic pathway in an UK hospital. They were trained on the use of type-III-cardiorespiratory polygraphy, which they took to use at home. They were also given AcuPebble_SA100; but they were not trained on how to use it.Participants182 consecutive patients had been referred for OSA diagnosis in which 150 successfully completed the study.Primary outcome measuresEfficacy of AcuPebble_SA100 for automated diagnosis of moderate–severe-OSA against cardiorespiratory polygraphy (sensitivity/specificity/likelihood ratios/predictive values) and validation of usability by patients themselves in their home environment.ResultsAfter returning the systems, two expert clinicians, blinded to AcuPebble_SA100’s output, manually scored the cardiorespiratory polygraphy signals to reach a diagnosis. AcuPebble_SA100 generated automated diagnosis corresponding to four, typically followed, diagnostic criteria: Apnoea Hypopnoea Index (AHI) using 3% as criteria for oxygen desaturation; Oxygen Desaturation Index (ODI) for 3% and 4% desaturation criteria and AHI using 4% as desaturation criteria. In all cases, AcuPebble_SA100 matched the experts’ diagnosis with positive and negative likelihood ratios over 10 and below 0.1, respectively. Comparing against the current American Academy of Sleep Medicine’s AHI-based criteria demonstrated 95.33% accuracy (95% CI (90·62% to 98·10%)), 96.84% specificity (95% CI (91·05% to 99·34%)), 92.73% sensitivity (95% CI (82·41% to 97·98%)), 94.4% positive-predictive value (95% CI (84·78% to 98·11%)) and 95.83% negative-predictive value (95% CI (89·94% to 98·34%)). All patients used AcuPebble_SA100 correctly. Over 97% reported a strong preference for AcuPebble_SA100 over cardiorespiratory polygraphy.ConclusionsThese results validate the efficacy of AcuPebble_SA100 as an automated diagnosis alternative to cardiorespiratory polygraphy; also demonstrating that AcuPebble_SA100 can be used by patients without requiring human training/assistance. This opens the doors for more efficient patient pathways for OSA diagnosis.Trial registration numberNCT03544086; ClinicalTrials.gov.

Exercise Intolerance and Oxygen Desaturation in Patients with Parkinson’s Disease: Triggers for Respiratory Rehabilitation?

The role that oxygen desaturation plays in exercise tolerance and its rehabilitative implications in patients with Parkinson’s disease (PD) are unclear. We aimed to test exercise tolerance and oxygen saturation levels both during exercise and at night in PD patients to better define their rehabilitative needs. In clinically stable PD patients, undergoing inpatient rehabilitation, and in “ON” phase, we prospectively assessed clinical data, sleepiness, comorbidities, PD severity (Hoehn&Yahr, HY), motor function (ADLs, UPDRSII and UPDRSIII, Barthel Index, Functional Independence Measure), balance, spirometry, respiratory muscles (MIP/MEP), peak cough expiratory flow (PCEF), continuous night oxygen monitoring, and meters at 6MWD. Of 55 patients analyzed (28 with moderate–severe PD, HY ≥ 2.5), 37% and 23% showed moderate–severe impairment on UPDRSII and UPDRSIII, respectively; 96% had reduced exercise tolerance and severe respiratory muscles impairment (MIP/MEP < 45%pred.); 21.8% showed desaturations during exercise; and 12.7% showed nocturnal desaturations. At multiple regression, low exercise tolerance and low mean nocturnal and exercise-induced saturation correlated with several respiratory and motor function and disability indices (all p < 0.03). Exercise tolerance, exercise-induced desaturations, and nocturnal desaturations were extremely frequent in PD patients and were worse in more severe PD patients. This suggests considering a combined role for motor and respiratory rehabilitation in these patients.

542. Use of Bamlanivimab in Cancer Patients with Mild-to-Moderate COVID-19

Background Bamlanivimab is a monoclonal antibody that was granted an emergency use authorization by the US Food and Drug Administration in November 2020 for patients with mild to moderate coronavirus disease 2019 (COVID-19). It initially showed promising results with decreasing hospitalizations and return emergency department visits in immunocompetent patients. We evaluated the role of bamlanivimab in the cancer patient population. Methods We conducted a retrospective matched study of all cancer patients diagnosed with mild to moderate COVID-19 who received bamlanivimab in our acute cancer care center (ACCC) from December 2020 to February 2021. These patients were compared to a control group of cancer patients who presented to our ACCC and were diagnosed with mild to moderate COVID-19 from March to November 2020 before the introduction of bamlanivimab. Control patients were matched by age and underlying malignancy. All patients had a baseline oxygen saturation ≥ 94% and an absolute neutrophil count &gt; 500 mm3. Demographics, clinical characteristics, and outcome that included COVID-related admissions, oxygen desaturation, ICU admission and 30-day mortality were compared in both groups. Results A total of 108 patients were analyzed with 54 patients in each group, of which 59% consisted of hematologic malignancies, and 33% were ≥ 65 years. The presenting symptoms were similar in both groups and mainly consisted of cough, fever, and dyspnea. Patients who received bamlanivimab were less likely to be admitted to the hospital (24% vs. 91%; p&lt; 0.0001), experience oxygen desaturation &lt; 94% during follow-up (11% vs 44%; p=0.0001), require oxygen supplement (7% vs. 44%; p&lt; 0.0001), or be admitted to the ICU (4% vs 15%; p=0.046). No 30-day mortality was observed in the bamlanivimab group with 2 (4%) occurring in the control group. However, the difference was not significant. Conclusion Bamlanivimab decreased hospital and ICU admissions in cancer patients. In addition, bamlanivimab reduced oxygen requirement and the risk of hypoxia and progression to severe disease in this patient population. Disclosures Samuel L. Aitken, PharmD, MPH, BCIDP, Melinta Therapeutoics (Individual(s) Involved: Self): Consultant, Grant/Research Support