Abstract
Background: Given that insulin resistance and lower levels of high-density lipoprotein cholesterol are reportedly associated with the development of coronary vasospasm, metabolic disorders may play a significant role in the underlying mechanisms of vasospastic angina (VSA). In this context, however, the impact of serum uric acid (SUA) levels on the diagnosis of VSA remains unclear. Methods: From May 2012 to March 2025, a total of 947 patients undergoing intracoronary acetylcholine (ACh) provocation tests for diagnosing VSA were included. Positive diagnosis of ACh provocation testing was defined as angiographic coronary spasm accompanied by chest symptoms and/or ischemic electrocardiographic changes. The primary interest of this study was to evaluate the potential relationship between SUA levels and ACh provocation test results. Results: Of the 947 patients, 497 (52.5%) had positive ACh provocation testing (i.e., VSA). Patients with positive ACh tests had significantly higher SUA levels than their counterparts (5.4 ± 1.6 vs. 5.2 ± 1.5 mg/dL, p = 0.039). The receiver operating characteristics curve analysis showed that SUA levels were predictive of positive ACh test results (area under the curve 0.538, best cut-off value 5.4 mg/dL, p = 0.040). In the multivariable logistic regression analysis, male sex and current smoking were identified as predictors of positive ACh testing, while SUA levels were not. Conclusions: Patients diagnosed with VSA had a higher SUA level than patients without VSA. However, this association was confounded with other factors, such as male sex and current smoking.