PRO53 CLOTTING FACTOR UTILIZATION AND BLEEDING RATES AMONG PERSONS WITH HEMOPHILIA A FROM A LONGITUDINAL STUDY

We compared participant characteristics between the Hemophilia Utilization Group Studies Part Va (HUGS-Va) and a long-term follow-up study (HUGS-LTS) to investigate the impact of changes of participants’ characteristics on annualized bleeding rates (ABR) in persons with hemophilia A, a genetic bleeding disorder. Self-reported bleeds were obtained from periodic HUGS-Va surveys conducted 2005-2007, and a 6-month recall survey from HUGS-LTS in 2014. Clotting factor dispensing records were collected prospectively for two years in HUGS-Va, and retrospectively for six months prior to HUGS-LTS. ABR and annualized factor dispensing (unit/kg body weight) were calculated and compared by age (children 2-11 years, adolescents 12-20 years, and adults ≥21 years) using ANOVA, and between the studies using paired T-tests. Sixty-nine participants completed both studies. Participants or parents of children participants had a higher rate of college education (76.5% vs. 98.5%) and full-year health insurance (88.4% vs. 95.7%) in HUGS-Va than in the HUGS-LTS. Adolescents and adults had an increased prophylactic treatment rate (60.0% to 78.6% and 30.8% to 69.2%, respectively) from HUGS-Va to HUGS-LTS, all P<0.05. Children had the highest mean/median factor dispensing (4822±4152/3300, 5061±3764/5336 IU/kg/year) and lowest mean/median ABR (3.9±4.4/2.8, 4.9±5.3/4.0); while adults had the lowest mean/median factor dispensing (2084±1870/1582, 4612±2571/4290 IU/kg/year) and highest ABR (12.4±9.2/14.0, 13.3±21.5/6.0) in both HUGS-Va and HUGS-LTS, respectively. Overall 70% of participants increased factor dispensing, while 51% of participants increased ABR. However, the mean/median ARB was not significant different between HUGS-Va (7.4±8.6/3.8) and HUGS-LTS (8.7±14.7/4.0), P=0.45. Participants who used episodic treatment had higher ABR (15.7) than those who used prophylactic treatment (10), P=0.41 in HUGS-LTS. Children and adolescents with higher factor dispensing showed lower ABR than adults, mean ABR had not significant changed while aging. Increased in rates of college educational and health insurance appear to increase use of prophylactic treatment and factor dispensing, which lowers ABR.