Joint outcomes in patients with haemophilia: the importance of adherence to preventive regimens.

In patients with severe haemophilia, spontaneous bleeding into joints initiates a sequence of events culminating in disabling arthropathy. Early evidence from Sweden suggested that clotting factor prophylaxis improved patient outcomes. Recent randomized, controlled trials comparing prophylaxis with on-demand treatment have definitively shown that prophylaxis reduces bleeding and improves joint outcomes in patients with severe haemophilia A. Available evidence also supports the effectiveness of prophylaxis in patients with haemophilia B. In the United States, fewer than half of all patients with severe haemophilia A or B are treated with prophylaxis, and in those receiving such treatment, adherence to prophylactic treatment regimens is low in many age groups. Barriers to prophylaxis include cost, difficulties associated with venous access and the time required for prophylactic infusions. Although concerns around adherence play an important role in the willingness of physicians to prescribe prophylaxis, individualized prophylactic regimens may help increase patient adherence. Clotting factors that are more convenient and less time-consuming to infuse also may improve adherence to prophylactic therapy. By promoting rigorous adherence to prophylactic clotting factor therapies, physicians may be able to help preserve joint function in patients with severe haemophilia.