AF and in-hospital mortality in COVID-19 patients

Background There are conflicting data on whether new-onset AF is independently associated with poor outcomes in Covid-19 patients. This study represents the largest dataset curated by manual chart review comparing clinical outcomes between patients with sinus rhythm, pre-existing and new-onset AF. Objective The primary aim of this study was to assess patient outcomes in Covid-19 patients with sinus rhythm, pre-existing and new-onset AF. The secondary aim was to evaluate predictors of new-onset AF in patients with Covid-19 infection. Methods Single-centre retrospective study of patients with a confirmed diagnosis of Covid-19 admitted between March and September 2020. Patient demographic data, medical history and clinical outcome data were manually collected. Adjusted comparisons were performed following propensity score matching between those with pre-existing or new-onset AF and those without AF. Results The study population comprised of 1241 patients. 94 patients (7.6%) had pre-existing AF and 42 patients (3.4%) developed new-onset AF. New-onset AF was associated with increased in-hospital mortality before (OR: 3.58, 95% CI 1.78-7.06, p<0.005) and after (OR: 2.80, 95% CI 1.01-7.77, p<0.005) propensity score matching compared with the no AF group. However, pre-existing AF was not independently associated with in-hospital mortality compared to patients with no AF (post-matching OR: 1.13, 95% CI 0.57-2.21, p=0.732). Conclusion New-onset AF, but not pre-existing AF, is independently associated with elevated mortality in patients hospitalised with Covid-19. This observation highlights the need for careful monitoring of Covid-19 patients with new-onset AF. Further research is needed to explain the mechanistic relationship between new-onset AF and clinical outcomes in Covid-19 patients.