Investigators from the US Centers for Disease Control and Prevention (CDC) and the Hemophilia Treatment Center Network (HTCN) conducted a retrospective study to determine whether patients with severe hemophilia A and an inhibitor were at an increased risk for death. The study “Impact of Inhibitors on Hemophilia A Mortality in the United States,” was published January 2015 in the American Journal of Hematology. The lead investigator of the study was Christopher Walsh, MD, director of the Hemophilia Program at the Mount Sinai School of Medicine in New York.


The study included 7,386 males with severe hemophilia A. Patient data for the study, from  May 1998 to September 2011, was culled from the CDC’s Universal Data Collection System (UDC). During that 13-year period, 432 participants died;  of those, 48 had an inhibitor.
Primary findings were as follows:

  • Males with severe hemophilia A who have an inhibitor are at increased risk of death.
  • Males with an inhibitor were 70% more likely to die compared to those without an inhibitor, even when other risks for death, such as older age, liver disease and infection with either HIV (the virus that causes AIDS) or hepatitis C virus, were taken into account.
  • Of the 48 patients with an inhibitor who died, 42% had a hemophilia-related cause of death (due to a bleeding complication) vs. only 12% of patients without an inhibitor who died of a bleeding-related complication.

Investigators admitted that before an inhibitor prevention strategy can be developed, existing data will need to be supplemented by additional surveillance. CDC is partnering with the HTCN to perform blood screening tests for inhibitors in patients enrolled in the Community Counts Program. This program is a new initiative designed to augment UDC data with ongoing inhibitor surveillance in cooperation with HTCs.


“The results of this testing will be used to determine the number of people with inhibitors in the US hemophilia population and collect information about when they occur,” concluded study authors. “Routine screening through this program or a hemophilia treatment center may uncover an inhibitor early in its development when treatment to eliminate it is more likely to be successful.”


Source: CDC, March 24, 2015