Hydroxyurea for secondary stroke prevention in children with sickle cell anemia in Nigeria: a randomized controlled trial.

We tested the hypothesis that fixed oral moderate-dose hydroxyurea (20 mg/kg per day) for initial treatment of secondary stroke prevention results in an 80% relative risk reduction of stroke or death when compared with fixed oral low-dose hydroxyurea (10 mg/kg per day) in a phase 3 double-blind, parallel-group, randomized controlled trial in children with sickle cell anemia (SCA) living in Nigeria. A total of 101 participants were randomly allocated to low-dose (n = 49) and moderate-dose (n = 52) hydroxyurea treatment groups. The median participant follow-up was 1.6 years (interquartile range, 1.0-2.3), with a planned minimum follow-up of 3.0 years. A total of 6 recurrent strokes and 2 deaths vs 5 recurrent strokes and 3 deaths occurred in the low- and moderate-dose groups, respectively. The incidence rate ratio (IRR) of the primary outcome measure of stroke or death in the low- and moderate-dose hydroxyurea treatment groups was 0.98 (95% confidence interval [CI], 0.32-3.00; P = .97). The trial was stopped early owing to no clinical difference in the incidence rates of the primary outcome measure. The incidence rates of recurrent strokes were 7.1 and 6.0 per 100 person-years in the low- and moderate-dose groups, respectively, (IRR, 1.18; 95% CI, 0.30-4.88; P = .74). As a measure of adherence to the oral hydroxyurea therapy, the median percent of returned pills was 3.0% and 2.6% in the low- and moderate-dose groups, respectively. No participant had hydroxyurea therapy stopped for myelosuppression. For children with SCA in low-income settings without access to regular blood transfusion therapy, initial low-dose hydroxyurea is a minimum known efficacious dose for secondary stroke prevention.

Barriers and Facilitators of Premarital Genetic Counseling for Sickle Cell Disease in Northern Nigeria.

In high-income countries, premarital genetic counseling for Sickle Cell Disease (SCD) is a standard practice. However, in Nigeria, there is no formal premarital genetic counseling program available for SCD. We conducted a series of focus group discussions with health care professionals, patients with SCD, and parents of the patients with or without SCD to gain an understanding of their attitudes and beliefs towards SCD/Sickle Cell Trait and premarital genetic counseling for SCD. Data were analyzed using Charmaz's constructivist grounded theory approach. Two themes were highlighted in the analysis as follows: (1) the difference between the perception of premarital sickle cell screening among individuals with SCD versus the general population, and (2) the personal beliefs and physical challenges that could lead to the avoidance of premarital screening within the general community. Lack of disease-related knowledge, testing facilities, transportation, and stigma associated with the disease were the most commonly perceived barriers to premarital testing. Also, a willingness to receive premarital testing for SCD exists within our community to reduce the spread of the disease and advocate for improved health-related quality of life of patients with SCD. The content and structure of a premarital genetic counseling program in Kano, Northern Nigeria, needs to be developed.

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.

Capacity Building for Primary Stroke Prevention Teams in Children Living With Sickle Cell Anemia in Africa.

BACKGROUND: Nigeria has the highest proportion of children with sickle cell anemia (SCA) globally; an estimated 150,000 infants with SCA are born annually. Primary stroke prevention in children with SCA must include Nigeria. We describe capacity-building strategies in conjunction with two National Institutes of Health-funded primary stroke prevention trials (a feasibility trial and phase III randomized controlled trial) with initial hydroxyurea treatment for children with SCA and abnormal transcranial Doppler (TCD) velocities in Nigeria. We anticipated challenges to conducting clinical trials in a low-resource setting with a local team that had not previously been involved in clinical research and sought a sustainable strategy for primary stroke prevention. METHODS: This is a descriptive, prospective study of challenges, solutions, and research teams in two trials that enrolled a total of 679 children with SCA. RESULTS: As part of the capacity-building component of the trials, over eight years, 23 research personnel (physicians, nurses, research coordinators, a statistician, and a pharmacist) completed a one-month research governance and ethics training program at Vanderbilt University Medical Center, USA. A lead research coordinator for each site completed the Society of Clinical Research Professionals certification. TCD machines were donated; radiologists and nonradiologists were trained and certified to perform TCD. A scalable E-prescription was implemented to track hydroxyurea treatment. We worked with regional government officials to support ongoing TCD-based screening and funding for hydroxyurea for children with SCA at a high risk of stroke. CONCLUSIONS: Our trials and capacity building demonstrate a sustainable strategy to initiate and maintain pediatric SCA primary stroke prevention programs in Africa.

Sickle Cell Disease Genomics of Africa (SickleGenAfrica) Network: ethical framework and initial qualitative findings from community engagement in Ghana, Nigeria and Tanzania.

OBJECTIVES: To provide lay information about genetics and sickle cell disease (SCD) and to identify and address ethical issues concerning the Sickle Cell Disease Genomics of Africa Network covering autonomy and research decision-making, risk of SCD complications and organ damage, returning of genomic findings, biorepository, data sharing, and healthcare provision for patients with SCD. DESIGN: Focus groups using qualitative methods. SETTING: Six cities in Ghana, Nigeria and Tanzania within communities and secondary care. PARTICIPANTS: Patients, parents/caregivers, healthcare professionals, community leaders and government healthcare representatives. RESULTS: Results from 112 participants revealed similar sensitivities and aspirations around genomic research, an inclination towards autonomous decision-making for research, concerns about biobanking, anonymity in data sharing, and a preference for receiving individual genomic results. Furthermore, inadequate healthcare for patients with SCD was emphasised. CONCLUSIONS: Our findings revealed the eagerness of patients and parents/caregivers to participate in genomics research in Africa, with advice from community leaders and reassurance from health professionals and policy-makers, despite their apprehensions regarding healthcare systems.

World Health Organization's Growth Reference Overestimates the Prevalence of Severe Malnutrition in Children with Sickle Cell Anemia in Africa.

Anthropometric indices are widely used to assess the health and nutritional status of children. We tested the hypothesis that the 2007 World Health Organization (WHO) reference for assessment of malnutrition in children with sickle cell anemia (SCA) overestimates the prevalence of severe malnutrition when compared to a previously constructed SCA-specific reference. We applied the WHO and SCA-specific references to children with SCA aged 5-12 years living in northern Nigeria (Primary Prevention of Stroke in Children with SCA in sub-Saharan Africa (SPRING) trial) to determine the difference in prevalence of severe malnutrition defined as body mass index (BMI) Z-score <-3 and whether severe malnutrition was associated with lower mean hemoglobin levels or abnormal transcranial Doppler measurements (>200 cm/s). A total of 799 children were included in the final analysis (median age 8.2 years (interquartile range (IQR) 6.4-10.4)). The application of the WHO reference resulted in lower mean BMI than the SCA-specific reference (-2.3 versus -1.2; p < 0.001, respectively). The use of the WHO reference when compared to the SCA-specific reference population also resulted in a higher prevalence of severe malnutrition (28.6% vs. 6.4%; p < 0.001). The WHO reference significantly overestimates the prevalence of severe malnutrition in children with SCA when compared to an SCA-specific reference. Regardless of the reference population, severe malnutrition was not associated with lower mean hemoglobin levels or abnormal transcranial Doppler (TCD) measurements.