Nationwide Trends in Reported Incidence of Takotsubo Cardiomyopathy from 2006 to 2012

Takotsubo cardiomyopathy (TC) is believed to be an increasingly diagnosed syndrome; however, data on its incidence are limited. The purpose of this study was to determine the reported incidence of TC in the United States and to examine its trend over several years. Data was obtained from the Nationwide Inpatient Sample, created by the Agency for Healthcare Research and Quality, for each of the years from 2006 to 2012. Hospital discharges with principal diagnosis of TC, identified using Internal Classification of Diseases, Ninth Revision, code 429.83, were included. We tabulated estimated total numbers of discharges, incidence per 100,000 persons, mean length of stay, inhospital death rates, and diagnoses stratified by age group and gender. The reported incidence of TC based on principal diagnosis at hospital discharge increased significantly over the study period, with 315 cases +/- 43 (standard error) in 2006 and 6,230 cases +/- 232 (standard error) in 2012 (p <0.001 for trend). Mean length of hospital stay was stable over the study period (3.4 days in 2006 vs 3.6 days in 2012; p = 0.74 for trend). The diagnosis was most frequent in patients aged 65 to 84 years (50% of all diagnoses in 2012), followed by those aged 45 to 64 years (39% of all diagnoses in 2012). Women accounted for >90% of diagnoses throughout the study period. In conclusion, the reported incidence of TC has increased significantly from 2006 to 2012, most likely because of increasing recognition of the syndrome. (C) 2015 Elsevier Inc. All rights reserved.