Establishing Sickle Cell Disease Stroke Prevention Teams in Africa is Feasible: Program Evaluation Using the RE-AIM Framework.

We used the Reach, Effectiveness, Adoption, Implementation, and Maintenance (RE-AIM) framework to evaluate a Stroke Prevention Team's readiness to prevent strokes in children with sickle cell anemia living in northern Nigeria. The NIH sponsored Stroke Prevention Trial in Nigeria included a goal of a sustainable stroke prevention program. The program's 1-year reach for transcranial Doppler screening was 14.7% (4710/32,000) of which 6.0% (281/4710) had abnormal velocities (≥200 cm/s). All participants with abnormal transcranial Doppler velocities were started on hydroxyurea (effectiveness). The leaders of all 5 hospitals agreed to adopt the program. After 1 year, program-implementation and maintenance rates were 100%, demonstrating the program's feasibility and short-term sustainability.

Primary prevention of stroke in children with sickle cell anemia in sub-Saharan Africa: rationale and design of phase III randomized clinical trial.

Strokes in children with sickle cell anemia (SCA) are associated with significant morbidity and premature death. Primary stroke prevention in children with SCA involves screening for abnormal transcranial Doppler (TCD) velocity coupled with regular blood transfusion therapy for children with abnormal velocities, for at least one year. However, in Africa, where the majority of children with SCA live, regular blood transfusions are not feasible due to inadequate supply of safe blood, cost, and the reluctance of caregivers to accept transfusion therapy for their children. We describe the Primary Prevention of Stroke in Children with Sickle Cell Disease in Nigeria Trial [StrokePreventioninNigeria (SPRING) trial, NCT02560935], a three-center double-blinded randomized controlled Phase III clinical trial to 1) determine the efficacy of moderate fixed-dose (20 mg/kg/day) versus low fixed-dose (10 mg/kg/day) hydroxyurea therapy for primary stroke prevention; 2) determine the efficacy of moderate fixed-dose hydroxyurea for decreasing the incidence of all cause-hospitalization (pain, acute chest syndrome, infection, other) compared to low fixed-dose hydroxyurea. We will test the primary hypothesis that there will be a 66% relative risk reduction of strokes in children with SCA and abnormal TCD measurements, randomly allocated, for a minimum of three years to receive moderate fixed-dose versus low fixed-dose hydroxyurea (total n = 220). The results of this trial will advance the care of children with SCA in sub-Saharan Africa, while improving research capacity for future studies to prevent strokes in children with SCA.

Primary stroke prevention in Nigerian children with sickle cell disease (SPIN): challenges of conducting a feasibility trial.

BACKGROUND: The majority of children with sickle cell disease (SCD), approximately 75%, are born in sub-Saharan Africa. For children with elevated transcranial Doppler (TCD) velocity, regular blood transfusion therapy for primary stroke prevention is standard care in high income countries, but is not feasible in sub-Saharan Africa. PROCEDURE: In the first U.S. National Institute of Health (NIH) sponsored SCD clinical trial in sub-Saharan Africa, we describe the protocol and challenges unique to starting a clinical trial in this region. We are conducting a single arm pilot trial of hydroxyurea therapy in children with TCD velocity ≥200 cm/sec in the middle cerebral arteries. Eligible children will be placed on hydroxyurea (n = 40) and followed for 3 years at Aminu Kano Teaching Hospital, Nigeria. Adherence will be measured via the Morisky Scale and adverse events will be determined based on hospitalization. RESULTS: Originally, a randomized placebo trial was planned; however, placebo was not approved by the local Ethics Committee. Hence a single arm trial of hydroxyurea will be conducted and five controls per patient with normal TCD measurements will be followed to compare the rate of adverse events to those with abnormal TCD measurements taking hydroxyurea. Using non-NIH funding, over 9 months, multiple face-to-face investigator meetings were conducted to facilitate training. CONCLUSION: A hydroxyurea trial (NCT01801423) for children with SCD is feasible in sub-Saharan Africa; however, extensive training and resources are needed to build a global patient oriented multi-disciplinary research team with a common purpose.