van Dijk Karin, van der Bom Johanna G, Lenting Peter J, de Groot Philip G, Mauser-Bunschoten Eveline P, Roosendaal Goris, Grobbee Diederick E, van den Berg H Marijke
Van Creveldkliniek, UMCU, Room C01.425 PO-Box 85500, 3508 GA Utrecht, The Netherlands.
Haematologica. 2005 Apr;90(4):494-8.
Patients with severe hemophilia A have considerably different factor VIII half-lives. Whether this is associated with their clinical characteristics has not been reported. The aim of this study was to describe the association of factor VIII half-lives with treatment and clinical characteristics of patients with severe hemophilia A, who have been treated with individually tailored prophylaxis.
Patients were selected from a single-center cohort of 214 patients with severe hemophilia, born between 1944 and 1995. To improve efficiency we measured factor VIII half-life in 42 patients selected from the extremes of the distribution of phenotypes of severe hemophilia. We assessed information on life-long joint bleeds and clotting factor consumption. Orthopedic outcome was assessed by the Pettersson score.
Among these patients with severe hemophilia, factor VIII half-life ranged from 7.4-20.4 hours (median 11.8 hours). A one-hour increase in factor VIII half-life was associated with 96 (95% confidence interval (CI) 2 -190) IU less clotting factor use per kg per year. Age was an important determinant of factor VIII half-life, and explained a large part of the association between factor VIII half-life and clotting factor consumption. The median number of joint bleeds per year and arthropathy were similar for patients with different half-lives.
Among patients with severe hemophilia, treated prophylactically with clotting factor, those with a shorter factor VIII half-life required slightly more clotting factor to prevent joint bleeds and subsequent arthropathy than similar patients with a longer factor VIII half-life.
重度甲型血友病患者的凝血因子 VIII 半衰期差异很大。其是否与临床特征相关尚无报道。本研究旨在描述凝血因子 VIII 半衰期与接受个体化预防性治疗的重度甲型血友病患者的治疗及临床特征之间的关联。
研究对象选自一个单中心队列，该队列包含 214 例出生于 1944 年至 1995 年间的重度血友病患者。为提高效率，我们从重度血友病表型分布的两端选取了 42 例患者测量凝血因子 VIII 半衰期。我们评估了终身关节出血和凝血因子消耗的信息。采用彼得松评分评估骨科结局。
在这些重度血友病患者中，凝血因子 VIII 半衰期为 7.4 - 20.4 小时（中位数为 11.8 小时）。凝血因子 VIII 半衰期每增加 1 小时，每年每千克体重的凝血因子使用量减少 96（95%置信区间(CI) 2 - 190）国际单位。年龄是凝血因子 VIII 半衰期的重要决定因素，并且在很大程度上解释了凝血因子 VIII 半衰期与凝血因子消耗之间的关联。不同半衰期患者每年的关节出血中位数和关节病情况相似。
在接受凝血因子预防性治疗的重度血友病患者中，凝血因子 VIII 半衰期较短的患者比半衰期较长的类似患者预防关节出血及后续关节病所需的凝血因子略多。
