Cross-sectional case-control studies (Blue)
Obstructive sleep apnoea (OSA) is associated with higher BMI, diabetes, older age and male gender, which are all risk factors for severe COVID-19. In this study, the authors aimed to study if OSA is an independent risk factor for COVID-19 infection or for severe COVID-19. OSA diagnosis and COVID-19 infection were extracted from hospital discharge, cause of death and infectious diseases registries in individuals who participated in the FinnGen study (n=260 405). Severe COVID-19 was defined as COVID-19 requiring hospitalisation. A multivariate logistic regression model was used to investigate associations. Comorbidities for either COVID-19 or OSA were selected as covariates. Moreover, a meta-analysis with previous studies was performed. 445 individuals with COVID-19 were included, 38 (8.5%) with OSA, of whom 19 out of 91 (20.9%) were hospitalised. OSA was associated with COVID-19 hospitalisation independent of age, sex, BMI and comorbidities (p-unadjusted=5.13×10-5, OR-adjusted=2.93 (95% CI 1.02 to 8.39), p-adjusted=0.045). OSA was not associated with the risk of contracting COVID-19 (p=0.25). A meta-analysis of OSA and severe COVID-19 showed an association across 15 835 COVID-19 positive controls, and 1294 patients with OSA with severe COVID-19 (OR=2.37 (95% 1.14 to 4.95), p=0.021). The authors concluded that the risk for contracting COVID-19 was the same for patients with OSA and those without OSA. In contrast, among COVID-19 positive patients, OSA was associated with higher risk of hospitalisation. These findings are in line with previous work and suggest OSA as an independent risk factor for severe COVID-19.