Practice patterns in haemophilia A therapy--a survey of treatment centres in the United States.

A survey was conducted to ascertain practice patterns for haemophilia A therapy in the United States. Questionnaire data were supplied by 52 haemophilia centres with a total of 4129 patients under treatment. Most participating centres were affiliated with academic/teaching hospitals or institutions. Patients below 5 years comprised 17% of the study population, 6-18 years 41% and >18 years 42%, and the apportionment across severity categories was 53% severe, 17% moderate and 30% mild. Among patients with severe haemophilia, 49% were receiving on-demand treatment, while 44% were receiving some form of prophylaxis (13% primary, 20% secondary and 11% tertiary). Primary prophylaxis was the most common type in children below 5 years of age, accounting for 25% of this age group. In children 6-18 years old, 58% were on some type of prophylactic regimen, while on-demand treatment was most frequent among adults. Difficulties of venous access were the most frequently cited barrier to instituting prophylaxis. Catheters were in use among 37% of the patients under primary prophylaxis and 14% of those on secondary prophylaxis. No major differences were observed in forms of therapy used between larger and smaller centres. These observations provide an extensive characterization of haemophilia A practice patterns in the United States.