Physical functioning in boys with hemophilia in the U.S.

BACKGROUND: Hemophilia is the most common inherited severe bleeding disorder. Although the most frequent complication of repeated hemorrhages is a crippling joint disease that begins in childhood, the extent of resultant joint functional impairment varies widely within the hemophilia population.
PURPOSE: The goal of this exploratory analysis was to examine a national database that collects information on boys with hemophilia, an X-linked severe congenital bleeding disorder, to determine characteristics associated with increased risk of developing limitations in physical functioning as an outcome of recurrent hemorrhages.
METHODS: A standard set of data is collected annually at ∼130 U.S. comprehensive hemophilia treatment centers (HTCs) in a voluntary surveillance program called the Universal Data Collection (UDC) program. Fifteen potential predictors for poor outcomes of physical functioning related to bleeding were examined for boys (aged ≤ 18 years) from 1998 to 2008. Bivariate and multivariate analyses of these predictors performed in 2009 examined associations with self-reported limitation of activities, absenteeism from work or school, and reliance on assistive devices for ambulation and mobility.
RESULTS: Multiple characteristics of underlying hemophilia severity and disease chronicity (in particular, increasing age, presence of joint bleeding, and inhibitor antibodies) were independently associated with increased risk of limitations of physical function. Nonwhite race/ethnicity was associated with each of the poorer functional outcomes in bivariate analyses. After controlling for the potential confounding effects of the multiple population characteristics on race, only African-American race was independently associated with activity restrictions, and African-American and Asian/Pacific Island ethnicity with absenteeism. With the exception of indicators of underlying disease severity, only obesity and medical insurance coverage with Medicaid rather than commercial insurance were independently associated with multiple poor outcomes.
CONCLUSIONS: Interventions focused on eliminating inhibitors, improving outcomes for African-American children with hemophilia, and maintaining healthy body weight are warranted. In addition, strategies are needed to assure adequate insurance coverage for all people with hemophilia to eliminate economic barriers to optimal functional outcomes.