Feldman B M, Pai M, Rivard G E, Israels S, Poon M-C, Demers C, Robinson S, Luke K-H, Wu J K M, Gill K, Lillicrap D, Babyn P, McLimont M, Blanchette V S
Division of Rheumatology, Hospital for Sick Children, Toronto, ON, Canada.
J Thromb Haemost. 2006 Jun;4(6):1228-36. doi: 10.1111/j.1538-7836.2006.01953.x.
Prophylactic treatment for severe hemophilia A is likely to be more effective than treatment when bleeding occurs, however, prophylaxis is costly. We studied an inception cohort of 25 boys using a tailored prophylaxis approach to see if clotting factor use could be reduced with acceptable outcomes.
Ten Canadian centers enrolled subjects in this 5-year study. Children were followed every 3 months at a comprehensive care hemophilia clinic. They were initially treated with once-weekly clotting factor; the frequency was escalated in a stepwise fashion if unacceptable bleeding occurred. Bleeding frequency, target joint development, physiotherapy and radiographic outcomes, as well as resource utilization, were determined prospectively.
The median follow-up time was 4.1 years (total 96.9 person-years). The median time to escalate to twice-weekly therapy was 3.42 years (lower 95% confidence limit 2.05 years). Nine subjects developed target joints at a rate of 0.09 per person-year. There was an average of 1.2 joint bleeds per person-year. The cohort consumed on average 3656 IU kg(-1)year(-1) of factor (F) VIII. Ten subjects required central venous catheters (three while on study); no complications of these devices were seen. One subject developed a transient FVIII inhibitor. End-of-study joint examination scores--both clinically and radiographically--were normal or near-normal.
Most boys with severe hemophilia A will probably have little bleeding and good joint function with tailored prophylaxis, while infusing less FVIII than usually required for traditional prophylaxis.
对于重度甲型血友病，预防性治疗可能比出血发生时的治疗更有效，然而，预防治疗成本高昂。我们研究了一组25名男孩的起始队列，采用定制的预防方法，以观察是否可以在获得可接受结果的情况下减少凝血因子的使用。
加拿大的10个中心招募了参与这项为期5年研究的受试者。儿童每3个月在血友病综合护理诊所接受随访。他们最初接受每周一次的凝血因子治疗；如果发生不可接受的出血，则逐步增加治疗频率。前瞻性地确定出血频率、靶关节的发展、物理治疗和影像学结果以及资源利用情况。
中位随访时间为4.1年（总计96.9人年）。升级至每周两次治疗的中位时间为3.42年（95%置信下限为2.05年）。9名受试者出现靶关节，发生率为每人每年0.09个。每人每年平均有1.2次关节出血。该队列平均每年消耗3656 IU kg(-1)的VIII因子。10名受试者需要中心静脉导管（3名在研究期间）；未观察到这些装置的并发症。1名受试者出现短暂的VIII因子抑制剂。研究结束时的关节检查评分——临床和影像学方面——均正常或接近正常。
大多数重度甲型血友病男孩通过定制的预防措施可能出血很少且关节功能良好，同时输注的VIII因子比传统预防所需的要少。
