Hospital charges attributable to a primary diagnosis of infectious diseases in older adults in the United States, 1998 to 2004

OBJECTIVES: To describe total and average hospital charges associated with infectious disease (ID) hospitalizations and specific ID categories and to estimate ID hospitalization rates in adults aged 65 and older in the United States from 1998 through 2004. DESIGN: Retrospective analysis of hospital discharge data obtained from the Nationwide Inpatient Sample for 1998 through 2004. SETTING: United States. PATIENTS: Older adults hospitalized in the United States from 1998 through 2004. MEASUREMENTS: Hospital charges and hospitalization rates for IDs described according to year, age group, sex, U.S. Census region, and ID category. Charges for non-ID hospitalizations were also described. Hospital charges were adjusted for inflation. RESULTS: From 1998 through 2004, total charges for ID hospitalizations exceeded $261 billion and accounted for 13% of all hospital charges for older adults. Total charges for ID hospitalizations increased from $31.4 billion in 1998 to $45.7 billion in 2004. The average annual ID hospital charge was lower than the average annual non-ID hospital charge during the study period ($21,342 vs $22,787, P<.001). The average annual rate for ID hospitalizations was 503 per 10,000 older adults, which remained stable during the study period. CONCLUSION: The total charges for ID hospitalizations and for all hospitalizations in older adults in the United States increased 45% and nearly 40%, respectively, during the 7-year study period, whereas the population of older adults grew by only 5%. Sustained increases of such magnitude will have major implications for the U.S. healthcare system as it prepares for the more than doubling of the older U.S. adult population during the first 30 years of this century.