Effects of HIV infection on age and cause of death for persons with hemophilia A in the United States

Health status and health-related quality of life associated with hemophilia

The hemophilias are a group of disorders associated with a chronic burden of morbidity and early mortality. Improvements in these adverse features have been achieved by the use of clotting factor concentrates within comprehensive centers of specialized care providing home infusion programs. Offsetting effects from transfusion-transmitted hepatitis and HIV infection are in recent decline. The net impact of these changes merits assessment. To test the a priori hypotheses that increasing severity of factor VIII deficiency would be associated with an increasing burden or morbidity and that hepatitis and HIV positivity would impair health status further, a cross-sectional study of a population-based cohort was undertaken in a regional hemophilia program in Ontario, Canada. A survey was made of mild, moderate, and severe hemophiliacs over 13 years of age who self-reported their health status using a standard 15-item questionnaire. The responses were converted to levels in the Health Utilities Index Mark 2 (HUI2) and Mark 3 (HUI3) health status classification systems to form multi-element vectors from which single-attribute morbidity and overall health-related quality of life utility scores were determined. The burden of morbidity was greater in hemophiliacs than in the general population and correlated with the category of disease (mild < moderate < severe). Hepatitis and HIV positivity conferred additional burdens of morbidity, which were mainly in the attributes of mobility (HUI2), ambulation (HUI3), and pain (HUI2/3), all of these differences reaching levels of statistical significance. Despite demonstrable improvements in the safety, effectiveness, and utilization of clotting factor concentrates, hemophiliacs continue to experience an important burden of morbidity. Measurement of this burden, as reported here, provides a basis for future economic evaluation of the costs and consequences of health care interventions provided to this population.

Factors predictive of death among HIV-uninfected persons with haemophilia and other congenital coagulation disorders

Historically, the leading cause of death among persons with haemophilia and other congenital coagulation disorders was uncontrolled bleeding. Mortality was associated with severe deficiency of coagulation factors VIII or IX and especially with high-titre antifactor neutralizing antibodies (inhibitors). The catastrophic contamination of plasma donor pools with human immunodeficiency virus (HIV) resulted in acquired immunodeficiency syndrome replacing haemorrhage as the leading cause of death among persons with haemophilia. Rather little has been written, however, about mortality among those not infected with HIV. The objective of this study was to identify conditions associated with all-cause mortality among HIV-uninfected patients who were followed for a mean of 8.8 years in the Multicentre Hemophilia Cohort Study. Among the 364 children (mean age 8 years), there were four deaths; two related to cancer, one to trauma, and the fourth to haemorrhage, end-stage liver disease and sepsis. Among the 387 HIV-uninfected adults (mean age 35 years) there were 29 deaths, with haemorrhage the leading cause of death, followed by hepatic, stroke and cancer deaths. Prognostic factors for all-cause mortality among the adults included haemophilia Type A with neutralizing antibodies [age-adjusted relative rate (RR) 3.1, 95% confidence interval (CI) 1.4-6.9] and serologic evidence of both hepatitis B and C virus (RR 4.1, 95% CI 0.97-17.6). Although hepatitis C viral load was slightly lower in patients with hepatitis B virus surface antigenaemia, it was unrelated to vital status. We conclude that causes of death and prognostic factors for current HIV-uninfected haemophilia patients are similar to those noted before the HIV epidemic. Better understanding, prevention and control of neutralizing antibodies and hepatitis infections may substantially improve longevity for people with haemophilia.

Mechanism of factor VIIa-dependent coagulation in hemophilia blood

The ability of factor VIIa to initiate thrombin generation and clot formation in blood from healthy donors, blood from patients with hemophilia A, and in anti-factor IX antibody-induced ("acquired") hemophilia B blood was investigated. In normal blood, both factor VIIa-tissue factor (TF) complex and factor VIIa alone initiated thrombin generation. The efficiency of factor VIIa was about 0.0001 that of the factor VIIa-TF complex. In congenital hemophilia A blood and "acquired" hemophilia B blood in vitro, addition of 10 to 50 nM factor VIIa (pharmacologic concentrations) corrected the clotting time at all TF concentrations tested (0-100 pM) but had little effect on thrombin generation. Fibrinopeptide release and insoluble clot formation were only marginally influenced by addition of factor VIIa. TF alone had a more pronounced effect on thrombin generation; an increase in TF from 0 to 100 pM increased the maximum thrombin level in "acquired" hemophilia B blood from 120 to 480 nM. Platelet activation was considerably enhanced by addition of factor VIIa to both hemophilia A blood and "acquired" hemophilia B blood. Thus, pharmacologic concentrations of factor VIIa cannot restore normal thrombin generation in hemophilia A and hemophilia B blood in vitro. The efficacy of factor VIIa (10-50 nM) in hemophilia blood is dependent on TF.