Introduction
Health disparities have been shown to exist in access to hematology care
for patients with sickle cell anemia (SCA) living in Alabama, especially
in rural areas of the state.1 To overcome the barrier
of transportation to the academic center in Birmingham, AL, the
University of Alabama at Birmingham (UAB) Pediatric Sickle Cell Program
developed satellite clinics throughout the state.2With the exception of transfusion therapy, patients living with sickle
cell can receive care at satellite clinics in Montgomery, Opelika, and
Tuscaloosa, AL. One clinical difference in available services at
satellite clinics, as compared to the UAB clinic, is that patients
receiving hydroxyurea (HU) therapy have their labs obtained on the day
of their clinic visit, but CBCs are performed in a local lab and faxed
back to the UAB Hematology office and fetal hemoglobin (HbF) levels are
processed in Birmingham when the medical team returns to the UAB campus.
Therefore, sickle cell providers do not have immediate access to HU
dosing labs during the satellite clinic visit. To address this barrier
of conducting HU monitoring clinic visits without immediate access to
labs, we developed a telehealth model in which a nurse receives the
faxed laboratory results, evaluates the laboratory values relevant to
our institutional HU dosing guidelines, confirms dosing changes to
achieve maximal tolerated dose with a sickle cell provider, and then
calls the patients to review laboratory results and educates on any
changes to the HU dosing plan.
Recent data identified that titrating HU to a maximal tolerated dose
leads to superior clinical outcomes as compared to lower dose
regimens.3 Therefore, sickle cell centers should
ensure that patients with SCA achieve their maximally tolerated dose of
HU. Novel techniques are being developed so that patients can be
initiated on a HU dose that is at or near their maximal tolerated
dose.4,5 Without this novel approach to initiate HU at
a maximal tolerated dose, clinical centers often achieve maximal
tolerated dosing and a high HbF level by titrating HU doses at each
visit based on CBC results, often targeting a specific neutrophil
count.6,7 Unique barriers may exist for programs
prescribing HU in satellite clinics and/or using telehealth or
telemedicine for dose adjustments if labs are not readily available.
Higher HbF levels and HU dosing have been achieved in other institutions
and during clinical trials as compared the mean levels at UAB;
therefore, our program identified a systematic need to improve HU
response to therapy among our patient population.6,8Prior to implementing any novel approaches to improve adherence, we
performed this study to determine if systematic barriers exist in HU
dosing adjustments based on our telehealth plan for satellite clinics.
We hypothesized that telemedicine dosing, where the medical provider
does not review laboratory results and make in-person HU dose adjustment
at the time of their medical visit, would not result in lower HU
response to therapy. To test this hypothesis, we evaluated the HU dosing
and adherence laboratory values for patients cared for at both the UAB
Pediatric Sickle Cell Clinic at Childrens of Alabama and satellite
clinics over a one year period. We also evaluated the association
between zipcode based socioeconomic indicators on HU response outcomes.