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.