PREDICTING PROGRESSION TO AIDS - AN EVALUATION OF 2 APPROACHES

This study evaluated the predictive validity of two clinical staging s ystems for HIV infection (the Rabeneck and Royce systems) using data o btained from the Department of Veterans Affairs Cooperative Study Numb er 298, a randomized clinical trial involving 335 symptomatic patients with CD4 counts of 200 to 500/mm(3). The relation between the HIV cli nical stages and progression to AIDS was examined using Kaplan-Meier e stimates, and Cox models were used to determine if the stages remained predictive after controlling for CD4 count. Both systems were signifi cant independent predictors of progression to AIDS. This work demonstr ates that simple, valid staging systems for HIV infection can be devel oped that provide greater prognostic distinction than the CD4 count al one.