Toxoplasmosis hospitalizations in the United States, 2008, and trends, 1993-2008

Abstract

Background: Toxoplasmosis-related hospitalizations often occur in persons with human immunodeficiency virus (HIV) infection and other causes of immunosuppression.

Methods: Using the National Inpatient Sample (NIS) from the Healthcare Cost and Utilization Project, we examined trends in toxoplasmosis-related hospitalizations by HIV infection status from 1993 through 2008, and rates by sex and race or ethnicity in 2008. The NIS is designed to represent a 20% sample of US community hospitals and currently includes information on up to 8 million discharges per year from ∼1000 hospitals. We used International Classification of Diseases, Ninth Revision, Clinical Modification codes 130-130.9 for toxoplasmosis and 042-044/795.8/795.71/V08 for HIV infection.

Results: Estimated HIV-associated toxoplasmosis hospitalizations increased from 9395 in 1993 to 10583 in 1995 (P = .0002), then dropped to 3643 in 2001 (P < .0001), with similar levels thereafter. The rate of HIV-associated toxoplasmosis hospitalizations among all HIV-related hospitalizations decreased from 3.33% in 1993 to 1.25% in 2008 (P < .0001). Estimated non-HIV-associated toxoplasmosis hospitalizations were less variable from 1993 to 2008 (range, 386-819; 0.0020% in 1993, 0.0015% in 2008). In 2008, the rates of both HIV- and non-HIV-associated toxoplasmosis hospitalizations were higher in Hispanic persons than in white persons.

Conclusions: HIV-associated toxoplasmosis hospitalizations dropped markedly after 1995 when highly active antiretroviral therapy was introduced; however, hospitalizations decreased relatively little after 2000, suggesting late diagnosis of some HIV-infected persons or antiretroviral therapy failure. Non-HIV-associated toxoplasmosis hospitalizations have been more stable. The rates of toxoplasmosis-related hospitalizations varied markedly among racial and ethnic groups.