Trends in Hospitalization Rates and Outcomes of Endocarditis Among Medicare Beneficiaries

Abstract

Objectives To determine the hospitalization rates and outcomes of endocarditis among older adults. Background Endocarditis is the most serious cardiovascular infection and is especially common among older adults. Little is known about recent trends for endocarditis hospitalizations and outcomes. Methods Using Medicare inpatient Standard Analytic Files, we identified all Fee-For-Service beneficiaries aged ≥65 years with a principal or secondary diagnosis of endocarditis from 1999-2010. We used Medicare Denominator Files to report hospitalizations per 100,000 person-years. Rates of 30-day and 1-year mortality were calculated using Vital Status Files. We used mixed-effects models to calculate adjusted rates of hospitalization and mortality and to compare the results before and after 2007, when the American Heart Association revised recommendations for endocarditis prophylaxis. Results Overall, 262,658 beneficiaries were hospitalized with endocarditis. The adjusted hospitalization rate increased from 1999-2005, reaching 83.5 per 100,000 person-years in 2005, and declined during 2006-2007. After 2007, the decline continued, reaching 70.6 per 100,000 person-years in 2010. Adjusted 30-day and 1-year mortality rates ranged from 14.2% to 16.5% and from 32.6% to 36.2%, respectively. There were no consistent changes in adjusted rates of 30-day and 1-year mortality after 2007. Trends in rates of hospitalization and outcomes were consistent across demographic subgroups. Adjusted rates of hospitalization and mortality declined consistently in the subgroup with principal diagnosis of endocarditis. Conclusions Our study highlights the high burden of endocarditis among older adults. We did not observe an increase in adjusted rates of hospitalization or mortality associated with endocarditis after publication of the 2007 guidelines.

Infective endocarditis and cancer in the elderly

“…We identified endocarditis from the principal or secondary ICD-9 diagnosis (see codes in table A1) of each admission recorded in the Medpar file [14]. From the PEDSF file, we determined demographic characteristics (age, sex, race, urbanicity), tumor features (TNM stage, grade of differentiation, SEER date of diagnosis) and census tract features (census region, percentage of black population, percentage of residents living below the poverty level, percentage of residents aged 25 or older with less than 12 years of education, percentage of residents speaking English not well/not at all at age 65+, median income).…”

Long-Term Clinical Outcome of Major Adverse Cardiac Events in Survivors of Infective Endocarditis

“…[1][2][3][4] Despite marked improvements in antibiotic therapy and surgical techniques, more than one third of affected patients die within the first year after hospitalization for IE. 1,5,6 IE is characterized by an intense inflammatory response that causes valvular endothelial damage after repeated insults by circulating bacteria. 7 Predisposing conditions may increase the rate of embolic events, which are associated with poor subsequent prognosis.…”

Temporal relationship between infective endocarditis and stroke

“…We identified all patients hospitalized with IE between July 1, 2007, and June 30, 2011, using the following previously validated ICD-9-CM codes for infective endocarditis: 421.0 (acute and subacute infective endocarditis), 421.1 (endocarditis, valve unspecified, in diseases classified elsewhere), 421.9 (acute endocarditis, unspecified), and 424.9 (endocarditis, valve unspecified). These codes have been frequently used in prior studies of endocarditis and have a positive predictive value of 81% and a sensitivity of 93% [12][13][14][15][16] for IE based on the modified Duke criteria. 17 Patients younger than 18 years of age were excluded because IE in children has been recognized as a different clinical entity from IE in adults, associated with different predisposing factors (e.g., congenital heart disease) and presenting far less often with extracardiac manifestations.…”