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.

Incidence, Characteristics and Clinical Relevance of Acute Stroke in Old Patients Hospitalized With COVID-19 (preprint)

Background: Stroke in the course of coronavirus disease (COVID-19) was associated with higher severity of respiratory symptoms and mortality, but little knowledge exists on older populations. We aimed to investigate the incidence, characteristics, and prognosis of acute stroke in old patients hospitalized with COVID-19. Methods: : Monocentric retrospective study of 265 older patients hospitalized with COVID-19 in geriatric wards, 11 of which having presented a stroke episode during hospitalization. Mortality rates and two-group comparisons (stroke vs non-stroke patients) were calculated and significant variables added in logistic regression models to investigate stroke risk factors. Results: : Combined ischemic and hemorrhagic stroke incidence was 4.15%. 72.7% of events occurred during acute care. Strokes presented with altered state of consciousness and/or delirium in 81.8%, followed by a focal neurological deficit in 45.5%. Ischemic stroke was more frequently unilateral (88.8%) and localized in the middle cerebral artery territory (55.5%). Smoking and a history of previous stroke increased by more than seven (OR 7.44; 95% CI 1.75-31.64; p=0.007) and five times (OR 5.19; 95% CI 1.50-17.92; p=0.009), respectively, the risk of stroke. Each additional point in body mass index (BMI) reduced the risk of stroke by 14% (OR 0.86; 95% CI 0.74-0.98; p=0.03). In-hospital mortality (32.1% vs. 27.3%; p>0.999) and institutionalization at discharge (36.4% vs. 21.1%; p=0.258) were similar between patients with and without stroke. Conclusion: Incident stroke complicating COVID-19 in old patients was associated with active smoking, previous history of stroke, and low BMI. Acute stroke did not influence early mortality or institutionalization rate at discharge.