Elevated Uric Acid Is Associated With New-Onset Atrial Fibrillation: Results From the Swedish AMORIS Cohort.

Background The role of uric acid is gaining increasing importance in the evaluation of cardiovascular disease, but its relationship with atrial fibrillation (AF) is unclear. This study aims to investigate the association between uric acid levels and risk of new-onset AF. Methods and Results A total of 339 604 individuals 30 to 60 years of age and free from cardiovascular disease at baseline (1985-1996) in the Swedish AMORIS (Apolipoprotein-Mortality Risk) cohort were followed until December 31, 2019 for incident AF. Cox regression models were used to examine the association between uric acid and AF, adjusting for potential confounders and stratifying by incident cardiovascular disease. Over a mean follow-up of 25.9 years, 46 516 incident AF cases occurred. Compared with the lowest uric acid quartile, each of the upper 3 quartiles were associated with an increased risk of AF in a dose-response manner. Adjusted hazard ratios were 1.09 (95% CI, 1.06-1.12) for second quartile, 1.19 (95% CI, 1.16-1.23) for third quartile, and 1.45 (95% CI, 1.41-1.49) for fourth quartile. The association was similar among individuals with and without incident hypertension, diabetes, heart failure, or coronary heart disease. The dose-response pattern was further supported in a subsample of individuals with repeated measurements of uric acid. Conclusions Elevated uric acid was associated with an increased risk of AF, not only among people with cardiovascular disease and cardiovascular risk factors but also among those without. Future investigations are needed to examine whether lowering uric acid is relevant for AF prevention.