Temporal Trends and Outcomes of Hospitalizations With Prinzmetal Angina: Perspectives From a National Database

Background: Contemporary data regarding the temporal changes in prevalence and outcomes of hospitalizations with Prinzmetal angina are limited. Methods: We queried the National Inpatient Sample Database for the years 2002-2015 to identify hospitalizations with Prinzmetal angina. We described the temporal trends and outcomes in patients with Prinzmetal angina. Results: A total of 97,280 hospitalizations with Prinzmetal angina were identified. There was a significant increase in the number of hospitalizations with Prinzmetal angina (3678 in 2002 vs 8633 in 2015, P_trend <.001) as well as the proportion of hospitalizations with Prinzmetal angina among those with chest pain (P_trend <.001). There was an increase in the rates of in-hospital mortality (0.24% in 2002 vs 0.85% in 2015, P_trend =.02), which corresponded to a progressive increase in the burden of comorbidities among patients with Prinzmetal angina. Age > 65 years, history of heart failure, chronic kidney disease, chronic liver disease, and acute myocardial infarction upon presentation were independent predictors of in-hospital mortality. Compared with patients with acute myocardial infarction without Prinzmetal angina, those with Prinzmetal angina presenting with acute myocardial infarction had a lower incidence of in-hospital mortality (odds ratio 0.24, 95% confidence interval 0.14-0.41). Conclusions: In this large national analysis, there has been an increase in the prevalence of hospitalizations with Prinzmetal angina. Older age, heart failure, chronic kidney disease, chronic liver disease, and acute myocardial infarction were predictors of higher mortality among patients with Prinzmetal angina. Patients with Prinzmetal angina who developed acute myocardial infarction had more favorable outcomes compared with myocardial infarction without Prinzmetal angina.