Impact of alcohol drinking on acetylcholine-induced coronary artery spasm in Korean populations

Background and aims Generally, immoderate alcohol consumption is associated with variant angina and accepted as one of the risk factors for coronary artery spasm (CAS), but evidence is lacking in this regard. The aim of this study is to evaluate the impact of alcohol consumption and drinking pattern on CAS by acetylcholine (ACH) provocation test and long-term clinical outcomes. Methods A total of 5491 patients with typical or atypical chest pain, without significant coronary artery disease, who underwent intracoronary ACH provocation test, were enrolled prospectively, and retrospectively analyzed in this study. They were divided into two groups according to their alcohol drinking status; the current alcohol (CA) drinking group (n = 1792), and non-CA group (n = 3699). To adjust for potential confounders, a propensity score matching (PSM) analysis was performed. The primary endpoint was incidence of CAS, and secondary endpoints were major adverse cardiac events (MACE) and recurrent angina requiring repeat coronary angiography (CAG) at 5 years. Results After PSM analysis, alcohol consumption was a strong risk factor for CAS. Furthermore, excessive alcohol consumption was correlated with a higher risk for CAS. As compared with the non-CA group, the CA group showed worse angiographic and clinical findings, including higher incidence of CAS (58% vs. 62%, p = 0.016), spontaneous spasm (17% vs. 22%, p = 0.004), multi-vessel spasm (31% vs. 37%, p = 0.009), proximal epicardial spasm (39% vs. 46%, p = 0.002), ischemic electrocardiography changes such as T-inversion (0.4% vs. 1.2%, p < 0.001) and chest pain (42% vs. 46%, p = 0.047) during ACH provocation test. However, the status and pattern of alcohol drinking had no influence on long-term clinical outcomes such as MACE or recurrent angina. Conclusions Alcohol consumption is a strong risk factor for CAS, and excessive alcohol consumption was correlated with a higher risk for CAS. Further well-designed studies are needed to confirm the results.