However, even though inhibitors, which can develop from factor VIII (FVIII) hemophilia therapy, were detected at an earlier age than previously reported, their presence was not associated with an increased risk of mortality according to the report published in Blood Advances (2020;4[19]:4739-47).
The researchers assessed 6,624 individuals born between 1920 and 2018 (5,694 [86.0%] men and 930 women) with NSHA from the ATHNdataset, according to Ming Y. Lim, MBBCH, MS, of the division of hematology and hematologic malignancies, University of Utah, Salt Lake City, and colleagues.
Demographically, the proportion of Black participants in the ATHNdataset was lower at 8.2%, than the 11.6% found in U.S. hemophilia population as a whole. A total of 77.3% (n = 5,122) had documented exposure to FVIII concentrates, 8.4% (n = 555) had no documented exposure, and information was unknown for the remaining 14.3%.
Causes of mortality
The researchers found that inhibitors occurred at an early age of 13 years with a prevalence of 2.6%, compared with the commonly reported median age of about 30 years for inhibitor development, but their presence was not associated with an increased risk of mortality, according to the authors. Instead, they found that mortality rates in the NSHA cohort were influenced by age, male sex, and hepatitis C and HIV infections.
The researchers speculated that the earlier age of inhibitor development may be due to the fact of the increased availability of FVIII concentrates over time, and that they may have been used more often from 2010 to 2018, compared with previously reported INSIGHT study (1980-2011).
In a multivariable analysis, men with NSHA were found to have 2.6 times the risk of death. Mortality risk increased twofold with each additional decade of age. Persons with hepatitis C had twice the risk of death and persons with HIV had almost four times the risk, compared with persons without these conditions.
The most common primary cause of death was malignancy (20.0%). The observed number of deaths from liver disease in the NSHA cohort was almost five times the expected death rate at 14%. Hemophilia-related deaths were 5.9%.
“Continued monitoring of persons with NSHA by comprehensive care visits at HTC should occur annually to address hemophilia-related issues and other age-related comorbidities, in collaboration with the primary care physician and other subspecialists. Importantly, we found that in the NSHA cohort, the development of inhibitors occurred at an earlier age than previously reported. This highlights the importance of routine monitoring for inhibitors in the NSHA population, regardless of age, especially if they have recently received intense factor replacement therapy,” the researchers concluded.
Ms. Lim reported no conflicts. Other authors reported research and consulting funding from a variety of pharmaceutical and biotechnology companies.
SOURCE: Lim MY et al. Blood Adv. 2020;4(19):4739-47.