Objective Uric acid (UA) is a cardiovascular risk marker associated with oxidative stress and inflammation. Recently, atrial fibrillation (AF) has been associated with inflammation and oxidative stress. The objective of this observational study was to investigate the association between UA levels and AF in hypertensive patients.
Methods Consecutive patients with hypertension were screened. We excluded subjects with coronary artery disease, congestive heart failure, diabetes, valvular heart disease, congenital heart disease, cardiomyopathy, renal failure, inflammatory conditions, thyroid dysfunction, respiratory diseases, and those who were taking drugs that affect UA metabolism (apart from diuretics). The final study population consisted of 451 patients. Fifty of them (11%) had AF (paroxysmal: 38; persistent: 8; permanent: 4). Demographic, clinical, laboratory, and echocardiographic characteristics were carefully recorded.
Results After univariate analysis, age, duration of hypertension, serum creatinine, serum UA, left atrial diameter (LAD), interventricular septum thickness, and left ventricular posterior wall thickness were significantly increased in patients with AF compared with non-AF patients, while the estimated glomerular filtration (eGFR) level was much lower in patients with AF than in those without AF. After multivariate logistic regression analysis, the independent predictors of AF were UA (OR: 1.008; 95% CI: 1.003-1.013, p=0.002) and LAD (OR: 1.160; 95% CI: 1.068-1.260; p<0.001).
Conclusion We demonstrated an independent association between increased serum UA levels and AF in hypertensive patients. Undoubtedly, larger studies in different populations should further examine this potential association as well as the underlying pathophysiological mechanisms.