Hyperuricemia: risk factor for thromboembolism in hypertrophic cardiomyopathy patients

Hyperuricemia has been regarded as a risk factor for various cardiovascular diseases. However, few studies have evaluated its influence on thromboembolism in hypertrophic cardiomyopathy (HCM) patients. The purpose of the present study is to investigate the association between hyperuricemia and thromboembolism in a retrospective HCM cohort. A total of 447 adult HCM patients were enrolled in this study from December 2008 to May 2016. Uric acid levels were measured at baseline. Hyperuricemia was defined as blood uric acid level > 360 µmol/L for female patients and > 420 µmol/L for male patients, respectively. The association between hyperuricemia and thromboembolism was analyzed. During the follow-up period of 1786.8 person-years, 31 patients (6.9%) developed thromboembolic events. There was a higher thromboembolism incidence in patients with hyperuricemia than those with normouricemia (8.9% vs. 5.6%; unadjusted HR 2.35, 95% CI 1.16-4.78, P = 0.018). The association slightly increased after adjusting for potential confounders (HR 2.67, 95% CI 1.24-5.76, P = 0.013). Atrial fibrillation (AF) and left ventricular outflow tract obstruction played an interactive role in the relationship between hyperuricemia and thromboembolism with P for interaction of 0.011 and 0.007, respectively. Adjusted HRs of hyperuricemia were 8.99 (95% CI 2.23-36.29, P = 0.002) for thromboembolism in HCM patients with AF and 6.89 (95% CI 2.23-21.24, P = 0.001) in non-obstructive HCM patients. The association lost statistical significance among patients without AF and obstructive ones. Hyperuricemia significantly predicts future thromboembolism in HCM patients, especially in HCM patients with AF and non-obstructive HCM patients. Future studies are warranted for further evaluation.