THROMBOCYTOPENIA IN HIV-INFECTED AND UNINFECTED HEMOPHILIACS

To determine the incidence and prognostic significance of thrombocytop enia among hemophiliacs, we analyzed clinical and hematologic data fro m the Multicenter Hemophilia Cohort study. Nineteen percent of HIV-inf ected subjects had thrombocytopenia (platelet count of <100,000/mm(3)) noted at least once, compared to 3% of HIV-uninfected subjects. For H IV-infected subjects, the prevalence of thrombocytopenia rose in the f irst 5 years after seroconversion and was twice as common in subjects age >35 years compared to younger subjects. The risk increased after a n AIDS-defining illness, particularly among older subjects, nearly one -half of whom had thrombocytopenia within 1 year after AIDS. When adju sted for age and CD4-positive lymphocyte counts, thrombocytopenia was associated with an increased risk of death [relative risk (RR) 1.7, 95 %Cl = 1.2-2.3] but with little change in the risk of progression to AI DS (RR = 1.2, 95%Cl = 0.8-1.7), Treatment with zidovudine was associat ed with a decreased risk of thrombocytopenia (RR = 0.5, 95%Cl = 0.3-0. 7). Although 59 HIV-infected subjects died of hemorrhage, only 11 (19% ) of the 59 had a reported platelet count of <50,000/mm(3), and only 2 (3%) of the deaths were temporally associated with thrombocytopenia. Thus, the risk of death was increased for thrombocytopenic HIV-infecte d hemophiliacs hut this was not explained by an increased risk of deve loping AIDS and was rarely associated with death from bleeding. (C) 19 97 Wiley-Liss, Inc.