Association between SARS-CoV-2 infection and new-onset atrial fibrillation.

BACKGROUND: Atrial fibrillation (AF) is associated with substantial morbidity and mortality. New-onset AF (NOAF) has been related recently to SARS-CoV-2 infection; however, the evidence supporting this link is still scarce. We aimed to examine the association between SARS-CoV-2 infection and NOAF. METHODS: We conducted a nested-case control study in a cohort of 2,931,046 adults from the largest healthcare provider in Israel. Subjects were followed from March 1st, 2020, until June 30th, 2022, for the occurrence of NOAF. Ten randomly selected controls were matched to each case of NOAF on age, sex, and duration of follow-up. Exposure to SARS-CoV-2 infection in the prior 30 days was assessed in cases and controls. To account for surveillance bias we performed a lag-time analysis and assessed the association with a negative control exposure (low back pain). Data was analyzed using conditional logistic regression. RESULTS: During the follow-up 18,981 patients developed NOAF and were matched to 189,810 controls. The mean age of cases and matched controls was 73.8 ± 13 years, and 51.1% of them were women. Multivariable analysis showed that SARS-CoV-2 infection was associated with an increased risk of NOAF; adjusted-OR, 4.24 (95% CI, 3.89-4.62). The association remained significant on lag-time analysis; however, the strength of the association was gradually attenuated with increasing lag-time but stabilized around a lag-time of 20 days. The negative control exposure (low back pain) was associated only with small increased risk of NOAF; adjusted-OR of 1.13 (95% CI, 1.02-1.26). CONCLUSION: SARS-CoV-2 infection appears to be associated with increased risk of NOAF.