Abstract
A retrospective study of 153 hemophiliacs infected with human immunodeficiency virusβ1 (HIVβ1) was performed to determine the clinical and immunological consequences of HIVβ1 infection and the markers and cofactors associated with these changes. Nearly 80% of HIVβ1βinfected hemophiliacs have developed a significant reduction in their CDβ4^+^ counts (<400 CDβ4^+^ cells/mm^3^) with 40% having less than 200 CDβ4^+^ cells/mm^3^ by the end of 1987. The rate of CDβ4^+^ cell count decline was slightly greater in patients who have already developed the acquired immunodeficiency syndrome (AIDS) compared to those who have not (50 vs. 31 cells/mm^3^/6 months). Thrombocytopenia and older age were associated with a more rapid CDβ4^+^ count deterioration, but the quantity of clotting factor utilized did not affect immunologic progression. In patients with < 200 CDβ4^+^ cells/mm^3^, the incidence of AIDS was significantly higher in adults (>21 years old) compared to children/adolescents. Cytomegalovirus (CMV) seroprevalence increased with age but did not correlate with the amount of concentrated clotting factor used. Although there was no relationship between CMV status and progression to AIDS, CMVβseropositive patients were older and had a lower CDβ4^+^ count. Thus the majority of HIVβ1βinfected hemophiliacs are developing progressive immune dysfunction measured by CDβ4^+^ count decline. This drop in CDβ4^+^ count significantly correlates with a risk for the development of AIDS in adults but not in children (<21 years old).