Importance: Prophylaxis and treatment guidelines for infective endocarditis have changed substantially over the past decade. In the United States, few population-based studies have explored the contemporary epidemiology and outcomes of endocarditis.
Objective: To quantify trends in the incidence and etiologies of infective endocarditis in the United States.
Design, setting, and participants: Retrospective population epidemiology study of patients hospitalized with a first episode of endocarditis identified from mandatory state databases in California and New York State between January 1, 1998, and December 31, 2013.
Exposure: Infective endocarditis.
Main outcomes and measures: Outcomes were crude and standardized incidence of endocarditis and trends in patient characteristics and disease etiology. Trends in acquisition mode, organism, and mortality were analyzed.
Results: Among 75 829 patients with first episodes of endocarditis (mean [SD] age, 62.3 [18.9] years; 59.1% male), the standardized annual incidence was stable between 7.6 (95% CI, 7.4 to 7.9) and 7.8 (95% CI, 7.6 to 8.0) cases per 100 000 persons (annual percentage change [APC], -0.06%; 95% CI, -0.3% to 0.2%; P = .59). From 1998 through 2013, the proportion of patients with native-valve endocarditis decreased (from 74.5% to 68.4%; APC, -0.7%; 95% CI, -0.9% to -0.5%; P < .001). Prosthetic-valve endocarditis increased (from 12.0% to 13.8%; APC, 1.3%; 95% CI, 0.8% to 1.7%; P < .001), and cardiac device-related endocarditis increased (from 1.3% to 4.1%; APC, 8.8%; 95% CI, 7.8% to 9.9%; P < .001). The proportion of patients with health care-associated nosocomial endocarditis decreased (from 17.7% to 15.3%; APC, -1.0%; 95% CI, -1.4% to -0.7%; P < .001). The proportion of patients with health care-associated nonnosocomial endocarditis increased (from 32.1% to 35.9%; APC, 0.8%; 95% CI, 0.5% to 1.1%; P < .001). The incidence of oral streptococcal endocarditis did not increase (unadjusted: APC, -0.1%; 95% CI, -0.8% to 0.6%; P = .77; adjusted: APC, -1.3%; 95% CI, -1.8% to -0.7%; P < .001). Crude 90-day mortality was unchanged (from 23.9% to 24.2%; APC, -0.3%; 95% CI, -1.0% to 0.4%; P = .44); adjusted risk of 90-day mortality decreased (adjusted hazard ratio per year, 0.982; 95% CI, 0.978 to 0.986; P < .001).
Conclusions and relevance: In California and New York State, the overall standardized incidence of infective endocarditis was stable from 1998 through 2013, with changes in patient characteristics and etiology over this time.