PURPOSE: The impacts of pre-existing atrial fibrillation (AF) on COVID-19-associated outcomes are unclear . We conducted a systematic review and meta-analysis to investigate the pooled prevalence of pre-existing AF and its short-term mortality risk in COVID-19 patients .
METHODS: Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed in abstracting data and assessing validity . We searched MEDLINE and Scopus to locate all the articles published up to January 31 , 2021, reporting data on pre-existing AF among COVID-19 survivors and non-survivors . The pooled prevalence of pre-existing AF was calculated using a random effects model and presenting the related 95% confidence interval (CI), while the mortality risk was estimated using the Mantel-Haenszel random effects models with odds ratio (OR) and related 95% CI . Statistical heterogeneity was measured using the Higgins I2 statistic .
RESULTS: Twelve studies, enrolling 15.562 COVID-19 patients (mean age 71.6 years), met the inclusion criteria and were included in the final analysis . The pooled prevalence of pre-existing AF was 11.0% of cases (95% CI : 7.8-15.2%, p <0.0001) with high heterogeneity (I2 = 95.2 %). Pre-existing AF was associated with higher risk of short-term death (OR 2.22 , 95% CI 1.47-3.36, p <0.0001), with high heterogeneity (I2 = 79.1 %).
CONCLUSION: Pre-existing AF is present in about 11% of COVID-19 cases but results associated with an increased risk of short-term mortality.