Clinical and Economic Burden of Hospitalizations for Infective Endocarditis in the United States

Objective: To assess contemporary trends in the incidence, characteristics, and outcomes of hospital admissions for infective endocarditis (IE) in the United States. Patients and Methods: Patients ≥18 years admitted with IE between January 1, 2003, and December 31, 2016, were identified in the National Inpatient Sample. We assessed the annual incidence, clinical characteristics, morbidity, mortality, and cost of IE-related hospitalizations. Results: The incidence of IE-related hospitalizations increased from 34,488 (15.9; 95% confidence interval [CI], 15.73, 16.06) per 100,000 adults) in 2003 to 54,405 (21.8; 95% CI, 21.60-21.97) per 100,000 adults) in 2016 (P<.001). The prevalence of patients below 30 years of age, and those who inject drugs, increased from 7.3% to 14.5% and from 4.8% to 15.1%, respectively (P<.001). The annual volume of valve surgery for IE increased from 4049 in 2003 to 6460 in 2016 (P<.001), but the ratio of valve surgery to IE-hospitalizations did not decrease (11.7% in 2003; 11.8% in 2016). There was also a temporal increase in risk-adjusted rates of stroke (8.0% to 13.2%), septic shock (5.4% to 16.3%), and mechanical ventilation (7.7% to 16.5%; P<.001). However, risk-adjusted mortality decreased from 14.4% to 9.8% (P<.001). Median length-of-stay and mean inflation-adjusted cost decreased from 11 to 10 days and from $45,810±$61,787 to $43,020±$55,244, respectively, (P<.001). Nonetheless, the expenditure on IE hospitalizations increased ($1.58 billion in 2003 to $2.34 billion in 2016; P<.001). Conclusions: There is a substantial recent rise in endocarditis hospitalizations in the United States. Although the adjusted in-hospital mortality of endocarditis and the cost of admission decreased over time, the overall expenditure on in-hospital care for endocarditis increased.