Survival after AIDS-defining events in patients with <200 lymphocytes CD4+ x 10⁶/L who are toxoplasmosis antibody positive

The objective of this study was to assess whether patients with CD4+ cell counts <200 x 10⁶/L have a decreased survival after the occurrence of any AIDS-defining event; 187 patients from the placebo arm of a clinical trial of toxoplasmosis prophylaxis (ANRS005-ACTG154) were included. For this analysis, patients were HIV infected without any AIDS-defining event, had a CD4+ lymphocyte count <200) x 10⁶/L, had a positive serology for Toxoplasma gondii, and had no severe liver, renal, or hematologic abnormalities. We used proportional hazards regression to study the relationships between baseline variables. AIDS-defining events as time-dependent variables, and survival. The risk of dying was increased by 1.9 for a 10-year increase in age and by 1.3 when CD4+ decreased by 50 x 10⁶/L; after the occurrence of a pneumocystosis, a cytomegalovirus infection, or a toxoplasmosis, the risk of dying was multiplied, respectively, by 10.9 (3.0-40.2), 10.0 (2.8-35.4), and 10.0 (4.5-22.2). None of the other AIDS-defining events was associated with an increased risk of dying, but the power to detect such an association was limited. We conclude that the occurrence of pneumocystosis, cytomegalovirus infection, or toxoplasmosis; age; and CD4+ cell count are important determinants of survival for HIV1-infected patients with CD4+ counts <200 x 10⁶/L who are toxoplasmosis antibody positive.