Atrial fibrillation and COVID-19 in older patients: how disability contributes to shape the risk profile. An analysis of the GeroCovid registry

Background and aims: Atrial fibrillation (AF) is often complicated by disabling conditions in the elderly. COVID-19 has high mortality in older people. This study aimed at evaluating the relationship of pre-infection AF with characteristics and survival of older COVID-19 patients. Methods: We retrospectively analyzed inpatients aged ≥ 60 years enrolled in GeroCovid Observational, a multicenter registry endorsed by the Italian and the Norwegian Societies of Gerontology and Geriatrics. Pre-COVID-19 sociodemographic, functional, and medical data were systematically collected, as well as in-hospital mortality. Results: Between March and June 2020, 808 COVID-19 subjects were enrolled (age 79 ± 9 years; men 51.7%). The prevalence of AF was 21.8%. AF patients were older (82 ± 8 vs. 77 ± 9 years, p < 0.001), had a higher CHA2DS2-VASc score (4.1 ± 1.5 vs. 3.2 ± 1.5, p < 0.001) and were more likely to present almost all comorbidities. At multivariable analysis, advanced age, white blood cell count, the presence of heart and peripheral artery diseases were significantly associated with the presence of AF. In-hospital mortality was higher in AF patients (36.9 vs. 27.5%; OR = 1.55, 95% CI = 1.09–2.20; p = 0.015). A decision tree analysis showed that, in AF subjects, preserved functional status at admission was the most important factor associated with survival. In patients without AF, baseline COVID-19 severity was the most relevant variable related to clinical prognosis. Conclusions: AF is frequent in older patients with COVID-19, in whom it associates with clinical complexity and high mortality. Pre-infection disability shapes the prognosis of this extremely vulnerable segment of hospitalized subjects. Clinical trial registration: GeroCovid Observational was registered at www.clinicaltrials.gov (NCT04379440).