Pediatric Clinics of North America - CIPERJ

364 RODRIGUEZ & HOOTS
was administered for 7.5 months (range 3 to 12 months) and long-term prophylaxis
was administered over 12 months. Almost half of patients in the
on-demand group occasionally had received short-term prophylaxis for several
months to a year. This study showed that clotting factor consumption
per year was similar for both treatment regimens (on-demand group:
median of 1260 IU/kg per /year; prophylaxis group: median 1550 IU/kg
per year). A significant difference, however, was that patients treated on
demand presented a 3.2-fold increase in the frequency of joint bleeds,
a 2.7-fold increase in clinical severity, and a 1.9-fold increase in Pettersson
scores. Not surprisingly, the quality of life for this group of patients was decreased.
Hence, these data support that the concept that prophylaxis may
improve clinical outcomes without significantly increasing treatment costs.
Tailored prophylaxis: individualizing therapy to patients’ needs
Because the natural history of arthropathy varies in patients who have
hemophilia, even considering those who are classified as having severe
hemophilia, tailoring prophylaxis to a patient’s bleeding pattern, joint
involvement, and individual needs seems a reasonable approach.
As discussed previously, data support initiating prophylaxis at an early
age to prevent joint damage. Particularly in young children, however, establishing
venous access commonly is a challenge and not surprisingly central
venous catheters (CVCs) often are required in this population for the administration
of multiple dosages of factor. The benefit of easy access provided
by such catheters must be balanced by their risks, in particular catheterrelated
infection.
Several studies have described different regimens to initiate prophylaxis
early on with a dual goal of preventing joint damage and minimizing the
need for CVC placement in young children. For example, Petrini [14] reported
that primary prophylaxis can be started using a weekly infusion of
factor concentrate rather than the standard 3-times-per-week prophylactic
regimen as early as 1 or 2 years of age. This approach reduces the need
for CVC placement in young children without increasing the occurrence
of hemarthrosis. Astermark and colleagues [5] reported in a similar study
that there was no difference in the occurrence of hemarthrosis or arthropathy
when comparing children who received factor VIII concentrate infusions
weekly during their first year of prophylaxis versus those who received prophylaxis
3 times a week.
In another study, published by van den Berg and colleagues [15], outcomes
of tailored prophylaxis were described for three cohorts according
to the time at which prophylaxis was started in relationship to the number
of joint bleeds. Data from this study also support the use of tailored prophylaxis
to prevent hemophilic arthropathy after a first joint bleed has occurred.
A prospective, multicenter Canadian study enrolling children who have
hemophilia is ongoing to evaluate frequency of infusions and dose