Regional disparity in outcomes among patients hospitalized for Takotsubo cardiomyopathy in the United States

Takotsubo cardiomyopathy (TTCM), an entity first described in Japan over two decades ago following myocardial stunning cases without evidence of coronary stenosis, has emerged as a unique entity with global recognition. We sought to investigate the extent and magnitude of regional variations in its outcomes. We used the National Inpatient Sample (NIS) of the Agency for Healthcare Research and Quality (2010–2014). Risk-adjusted rates of outcomes across the US geographical regions were calculated by fitting a Poisson regression model with a robust error variance under generalized estimating equations. Discrete numeric variables with over-dispersed count distributions -length of stay and continuous variables with a right skewed spread- cost of hospitalization were modeled using a generalized linear regression with a negative binomial function and gamma function respectively. We found significant regional variations in-patient mortality. While there was significantly higher risk of in-hospital death in the West (5.28 [4.34–6.44]) vs 4.40 [3.57–5.43] vs 4.10 [3.38–498] vs 4.78 [3.96–5.77]), there was a different pattern of variation in the length of days with longer hospital stay in the Northeast. Likewise, the risk-adjusted rate of non-routine home discharges was highest for Northeast. The West had the highest cost of hospitalization (West: $40,217 vs. South: $28,465) Significant geographic variation exists in the cost of hospitalization and in-hospital mortality of TTCM across the US. Understanding this variation requires a detailed understanding of the processes of care and identification of effective strategies to eliminate these disparities.