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

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.