Contemporary trends in the incidence of spontaneous coronary artery dissection (SCAD) - ethnic and household income disparities

Objectives: Spontaneous coronary artery dissection (SCAD) may contribute to 35% of acute coronary syndrome among women <= 50 years of age. We aimed to investigate the overall incidence, as well as the trends of SCAD incidence based on race, household income, and the U.S. census regions utilizing the National Inpatient Sample. Methods: In this retrospective cohort study the discharge data were extracted from the NIS using 9th and 10th revisions of the International Classification Disease for SCAD. Results: We found that the incidence of SCAD is rising in all U.S. census regions, and patients were predominantly females. Overall crude incidence of SCAD per 1,000,000 discharges per year was found to be 4.95 (2010), 5.73 (2011), 5.34 (2012), 6.18 (2013), 7.64 (2014), 8.11 (2015), 14.58 (2016), and 14.81 (2017). There was a higher incidence of SCAD in white population and higher-income groups. Among U.S. census regions, West has had the highest incidence followed by the Northeast, Midwest, and South. Statistically significant differences were observed in year-to-year SCAD incidence among racial groups, household income quintiles, and U.S. census regions (P < 0.0001). Conclusion: Recent trends indicate that the incidence is highest among White race, highest household income quintile, and in U.S. CENS-R4 (Census Region 4: West). These findings defy classic racial trends in cardiovascular disease burden which need further discovery.