Community Counts Study Identifies Predictors of Joint Bleeding in Severe Hemophilia
An analysis from the Community Counts Longitudinal Surveillance Cohort national surveillance project has identified key predictors of joint bleeding among individuals with severe hemophilia A and B, shedding light on treatment efficacy and demographic risk factors in the era of advanced prophylaxis.
Drawing from 7211 observation years across 2527 patients between 2013 and 2022, researchers assessed joint bleeding patterns in individuals on continuous prophylaxis without inhibitors. The mean annual joint bleeding rate (AJBR) was 1.45 for hemophilia A and 1.08 for hemophilia B, confirming prior evidence that hemophilia B is associated with less frequent joint bleeding.
Crucially, the study found that use of emicizumab, a factor VIII mimetic, was the strongest predictor of reduced AJBR in hemophilia A. Other independent protective factors included younger age, fewer missed doses, full employment, higher education, commercial insurance, and treatment at hemophilia treatment centers (HTCs) in the Northeast US. Notably, demographics such as race—particularly Asian—and being underweight were also associated with lower AJBR in hemophilia A.
For hemophilia B, fewer factors emerged as significant. Only younger age and Northeast US care location independently predicted lower joint bleeding rates. The study attributed the lack of other associations partly to the lower bleeding frequency and smaller sample size in the hemophilia B cohort.
The authors emphasized the importance of comprehensive care strategies, including improving access to newer therapies and promoting adherence, to optimize joint health in hemophilia patients.
The study, one of the largest of its kind, underscores the complex interplay between patient, community, and therapeutic variables in managing hemophilia-related joint disease.
Reference
Manco-Johnson MJ, Le B, Acharya S, et al. Risk factors for joint bleeding in severe hemophilia A and B: analysis of the Community Counts Longitudinal Surveillance Cohort. Blood Vessel Thromb Hemost. 2025;100047. doi:https://doi.org/10.1016/j.bvth.2025.100047
