Summary
This study updates estimates of the cumulative incidence of AIDS among Italian patients
with congenital coagulation disorders (mostly hemophiliacs), and elucidates the role
of age at seroconversion, type and amount of replacement therapy, and HBV co-infection
in progression. Information was collected both retrospectively and prospectively on
767 HIV-1 positive patients enrolled in the on-going national registry of patients
with congenital coagulation disorders. The seroconversion date was estimated as the
median point of each patient’s seroconversion interval, under a Weibull distribution
applied to the overall interval. The independence of factors associated to faster
progression was assessed by multivariate analysis. The cumulative incidence of AIDS
was estimated using the Kaplan-Meier survival analysis at 17.0% (95% Cl = 14.1-19.9%)
over an 8-year period for Italian hemophiliacs. Patients with age greater than or
equal to 35 years exhibited the highest cumulative incidence of AIDS over the same
time period, 32.5% (95% Cl = 22.2-42.8%). Factor IX recipients (i.e. severe B hemophiliacs)
had higher cumulative incidence of AIDS (23.3% vs 14.2%, p = 0.01) than factor VIII
recipients (i.e. severe A hemophiliacs), as did severe A hemophiliacs on less-than-20,000
IU/yearly of plasma-derived clotting factor concentrates, as opposed to A hemophiliacs
using an average of more than 20,000 IU (18.8% vs 10.9%, p = 0.02). No statistically
significant difference in progression was observed between HBsAg-positive vs HBsAg-negative
hemophiliacs (10.5% vs 16.4%, p = 0.10). Virological, immunological or both reasons
can account for such findings, and should be investigated from the laboratory standpoint.
