Stroke Prevention and Treatment for Youth with Sickle Cell Anemia: Current Practice and Challenges and Promises for the Future.

PURPOSE OF REVIEW: Sickle cell anemia (SCA) is an autosomal recessive inherited hemoglobinopathy that results in a high risk of stroke. SCA primarily affects an underserved minority population of children who are frequently not receiving effective, multi-disciplinary, preventative care. This article reviews primary and secondary stroke prevention and treatment for children with SCA for the general adult and pediatric neurologist, who may play an important role in providing critical neurologic evaluation and care to these children. RECENT FINDINGS: Primary stroke prevention is efficacious at reducing ischemic stroke risk, but it is not consistently implemented into clinical practice in the United States, resulting in these children remaining at high risk. Acute symptomatic stroke management requires neurology involvement and emergent transfusion to limit ischemia. Furthermore, while chronic transfusion therapy is a proven secondary preventative modality for those with prior symptomatic or silent cerebral infarcts, it carries significant burden. Newer therapies (e.g., stem cell therapies and voxelotor) deserve further study as they may hold promise in reducing stroke risk and treatment burden. Effective primary and secondary stroke prevention and treatment remain a challenge. Informing and engaging neurology providers to recognize and provide critical neurologic evaluation and treatment has potential to close care gaps.

Sexually transmitted infection testing and diagnosis in adolescents and young adults with sickle cell disease.

BACKGROUND: Sexually transmitted infections (STIs) are common and disproportionately affect Black adolescents and young adults (AYAs). Less is known about STIs among Black AYAs with chronic conditions, such as sickle cell disease (AYAs-SCD). This study compared STI testing and diagnosis between AYAs-SCD and their peers, overall and among STI-related encounters. PROCEDURE: This retrospective, cross-sectional study used diagnosis and billing codes in the Pediatric Health Information System (PHIS) to identify inpatient and emergency department encounters from January 1, 2022 to May 31, 2023 among all AYAs 15-24 years and those with STI-related diagnoses (e.g., "cystitis"). STI testing and diagnosis rates were compared between AYAs-SCD, non-Black AYAs, and Black AYAs, controlling for age, sex, and encounter setting. RESULTS: We identified 3602 AYAs-SCD, 177,783 Black AYAs, and 534,495 non-Black AYAs. AYAs-SCD were less likely to be tested for STIs than non-Black AYAs (odds ratio [OR] = 0.26; adj. p < .001) and Black AYAs (OR = 0.53; adj. p < .001). When tested, AYAs-SCD were more likely to be diagnosed with an STI than non-Black AYAs (OR = 2.39; adj. p = .006) and as likely as Black AYAs (OR = 0.67; adj. p = .15). Among STI-related encounters, AYAs-SCD were less likely to be tested than non-Black AYAs (OR = 0.18; adj. p < .001) and Black AYAs (OR = 0.44; adj. p < .001). No significant differences in STI diagnoses were found in this subset between AYAs-SCD and non-Black AYAs (OR = 0.32; adj. p = .28) or Black AYAs (OR = 1.07; adj. p = .99). CONCLUSIONS: STI care gaps may disproportionately affect AYAs-SCD. STIs should be considered when evaluating symptomatic AYAs-SCD in acute settings. More research is needed to further contextualize STI care for AYAs-SCD.

Influenza vaccine uptake among youth with sickle cell disease who are seen in clinic before and after the COVID-19 pandemic.

Influenza vaccination is critical for children with sickle cell disease (SCD) due to risks of severe influenza infections. Despite declining influenza vaccination among children since the COVID-19 pandemic, less is known about influenza vaccine coverage among youth with SCD during this same period. We compared influenza vaccine uptake among youth with SCD seen by a SCD provider in clinic during the 2019-2020 and 2022-2023 influenza seasons and described infection characteristics. Overall, 85% (n = 220) of children received their influenza vaccine during 2019-2020 compared to 75% (n = 245) in 2022-2023 (p = 0.059). Participants seen during both seasons were more likely to shift from vaccinated in 2019-2020 to unvaccinated in 2022-2023 than vice versa (McNemar's OR = 3.0; p = 0.008). Among 66 documented infections, 25.8% resulted in hospitalization. We found high influenza vaccine uptake but those seen during both seasons were more likely to become unvaccinated. More research is needed to understand influenza vaccine decision-making in this population.

Study protocol for ADHERE (Applying Directly observed therapy to HydroxyurEa to Realize Effectiveness): Using small business partnerships to deliver a scalable and novel hydroxyurea adherence solution to youth with sickle cell disease.

Sickle cell disease (SCD) is an inherited blood disorder that affects approximately 100,000 Americans, primarily from underrepresented racial minority populations, and results in costly, multi-organ complications. Hydroxyurea, the primary disease-modifying therapy for SCD, is effective at reducing most complications; however, adherence to hydroxyurea remains suboptimal and is the primary barrier to clinical effectiveness. Video directly observed therapy (VDOT) has shown promise as an adherence-promoting intervention for hydroxyurea, yet previous VDOT trials were limited by high attrition from gaps in technology access, use of unvalidated adherence measures, and healthcare system limitations of delivering VDOT to patients. As such, we fostered a small business partnership to compare VDOT for hydroxyurea to attention control to address previous shortcomings, promote equitable trial participation, and maximize scalability. VDOT will be administered by Scene Health (formerly emocha Health) and adherence monitoring will be performed using a novel electronic adherence monitor developed to meet the unique needs of the target population. Adolescent and young adult patients as well as caregivers of younger patients (<11 years of age) will be recruited. In addition to visit incentives, all participants will be offered a smartphone with a data plan to ensure all participants have equal opportunity to complete study activities. The primary objectives of this pilot, multi-center, randomized controlled trial (RCT) are to assess retention and sustained engagement and to explore needs and preferences for longer-term adherence monitoring and interventions. This RCT is registered with the National Institutes of Health (NCT06264700). Findings will inform a future efficacy RCT applying VDOT to hydroxyurea to address adherence gaps and improve outcomes within this vulnerable population.

Using the consolidated framework for implementation research to identify challenges and opportunities for implementing a reproductive health education program into sickle cell disease care.

BACKGROUND: As survival rates for individuals with sickle cell disease (SCD) increase, calls have been made to improve their reproductive healthcare and outcomes. The research team created a web-based program entitled Fertility edUcaTion to Understand ReproductivE health in Sickle cell disease (FUTURES). The study aim was to use the Consolidated Framework for Implementation Research (CFIR) during pre-implementation to identify challenges and opportunities from the individual to systems level of implementation to ultimately optimize the integration of FUTURES into clinical practice. METHODS: Semi-structured interviews were conducted with clinicians, research team members, and adolescent and young adult (AYA) males with SCD and their caregivers who participated in pilot testing. Interviews (N = 31) were coded inductively and then mapped onto CFIR domains (i.e., outer setting, inner setting, characteristics of individuals, and intervention characteristics). RESULTS: Research team interviews indicated the lack of universal guidelines for reproductive care in this population and gaps in reproductive health knowledge as key reasons for developing FUTURES, also highlighting the importance of collaboration with community members during development. Clinicians reported intraorganizational communication as essential to implementing FUTURES and discussed challenges in addressing reproductive health due to competing priorities. Clinicians, AYAs, and caregivers reported positive views of FUTURES regarding length, engagement, accessibility, and content. Suggestions for the best setting and timing for implementation varied. CONCLUSIONS: Using CFIR during the pre-implementation phase highlighted challenges and opportunities regarding integrating this program into SCD care. These findings will inform adaptation and further testing of FUTURES to ensure effective implementation of this novel education program.

Prevalence of Duffy null and its impact on hydroxyurea in young children with sickle cell disease in the United States.

Consistent with studies showing a high prevalence of the Duffy null phenotype among healthy Black Americans, this retrospective study found that Duffy null was present in >75% of a young and contemporary cohort of children with sickle cell disease (SCD) in the United States. Despite the potential for this phenotype to impact absolute neutrophil counts, hydroxyurea (HU) dosing, and outcomes, it was not associated with being prescribed a lower HU dose or having increased acute SCD visits early in the HU treatment course. Future studies are needed to confirm these findings in older children with SCD.

Experiences and outcomes of fertility testing in male adolescents with sickle cell disease.

Adult males with sickle cell disease (SCD) may have abnormal semen parameters, raising the concern that SCD and/or treatments may impact fertility. Yet, studies that include adolescents are lacking. To determine if fertility testing is feasible in male adolescents with SCD, and to explore their experiences and outcomes of fertility testing, 33 adolescents who completed a web-based SCD reproductive health education program were offered a free semen analysis. Five (15%) obtained testing and each had abnormalities. Barriers to testing included lack of time and transportation and discomfort. Findings highlight the need for larger, longitudinal studies using innovative testing approaches.

Comparing super-utilizers and lower-utilizers among commercial- and Medicare-insured adults with sickle cell disease.

ABSTRACT: Sickle cell disease (SCD) is a rare but costly condition in the United States. Super-utilizers have been defined as a subset of the population with high health care encounters or expenditures. Although super-utilizers have been described in other disease states, little is known about super-utilizers among adults with SCD. This study aimed to characterize the differences in expenditures, overall health care encounters, and pain episode encounters between super-utilizers (top 10% expenditures) and lower-utilizers with SCD (high, top 10%-24.9%; moderate, 25%-49.9%; and low, bottom 50% expenditures). A retrospective longitudinal cohort of adults with SCD were identified using validated algorithms in MarketScan and Medicare claim databases from 2016 to 2020. Encounters and expenditures were analyzed from inpatient, outpatient, and emergency department settings. Differences in encounters and expenditures between lower-utilizers and super-utilizers were compared using logistic regression. Among super-utilizers, differences in encounters and expenditures were compared according to incidences of pain episode encounters. The study population included 5666 patients with commercial insurance and 8600 with Medicare. Adjusted total annual health care expenditure was 43.46 times higher for super-utilizers than for low-utilizers among commercial-insured and 13.37 times higher in Medicare-insured patients. Among super-utilizers, there were patients with few pain episode encounters who had higher outpatient expenditures than patients with a high number of pain episode encounters. Our findings demonstrate the contribution of expensive outpatient care among SCD super-utilizers, in which analyses of high expenditure have largely focused on short-term care. Future studies are needed to better understand super-utilizers in the SCD population to inform the effective use of preventive interventions and/or curative therapies.

Primary care use and depression screening among young adults with sickle cell disease during their final year of pediatric hematology care.

Depression may contribute to transition risk among young adults with sickle cell disease (SCD). It is unclear if they receive depression screening because primary care providers (PCPs) routinely perform this screening, but PCP use declines with age. This retrospective study of young adults with SCD during their final year of pediatric hematology care identified 51 (91%) had PCPs. Among those with hospital system PCPs, 20% saw their PCP and 50% of those were screened for depression by the PCP. This suggests young adults with SCD may not receive depression screening or see PCPs, leading to potential missed opportunities for intervention.

Comparison of thromboembolism outcomes in patients with sickle cell disease prescribed hormonal contraception.

Patients with sickle cell disease (SCD) are at a risk of thromboembolism (TE), and use of hormonal contraception can further increase that risk. This study aims to assess patterns of hormonal contraceptive use and compare risk of contraception-related TE between combined hormonal contraceptives (CHCs) and progestin-only contraceptives (POCs). Patients with SCD aged between 12 and 44 years with a new prescription of a hormonal contraceptive in the Centers for Medicare and Medicaid Services Medicaid Analytic eXtract database (2006-2018) were followed up to 1 year. We identified 7173 new users: 44.6% initiated CHC and 55.4% initiated POC. Combined oral contraceptive pills (OCPs; 36.5%) and progestin-only depot medroxyprogesterone acetate (33.9%) were the most frequently prescribed agents. A total of 1.8% of contraception users had a new diagnosis of TE within 1 year of the first identified contraception prescription. There were no significant differences in TE event rates between CHC and POC users (17.2 and 24.7 events per 1000 person-years, respectively). In patients prescribed OCP, there were no differences in TE event rates based on estrogen dose or progestin generation. Transdermal patch had a 2.4-fold increased risk of TE as compared with that of OCP. Although limited by the retrospective study design and use of administrative claims data, this study found no significant differences in TE rates between new users of CHC and POC in patients with SCD. Careful evaluation of underlying TE risk factors should be considered for each patient with SCD before initiation of hormonal contraception.

Pregnancy-related thromboembolism in women with sickle cell disease: An analysis of National Medicaid Data.

Pregnancy and sickle cell disease (SCD) both individually carry a risk of thromboembolism (TE). Pregnancy in people with SCD may further enhance the prothrombotic effect of the underlying disease. The objectives of this study were to determine the rate and risk factors for arterial and venous thrombosis in pregnant people with SCD. Administrative claims data from the United States Centers for Medicare and Medicaid Service Analytic eXtract from 2006 to 2018 were used. The study population included people with SCD from the start of their first identified pregnancy until 1 year postpartum and a control cohort of pregnant people without SCD of similar age and race. Outcomes of interest were identified with ICD-9 or 10 codes. Logistic regression analyses were used to analyze risk factors. We identified infant deliveries in 6388 unique people with SCD and 17 110 controls. A total of 720 venous thromboembolism (11.3%) and 335 arterial TE (5.2%) were observed in people with SCD compared to 202 (1.2%) and 95 (0.6%) in controls. People with SCD had an 8-11 times higher odds of TE compared to controls (p < .001). Within the SCD cohort, age, hemoglobin SS (HbSS) genotype, hypertension, and history of thrombosis were identified as independent risk factors for pregnancy-related TE. Pregnancy-specific factors (pre-eclampsia, eclampsia, multigestational pregnancy) were not associated with TE. In conclusion, the risk of pregnancy-related TE is considerably higher in people with SCD compared with controls without SCD. Hence, people with SCD, particularly those with multiple risk factors may be candidates for thromboprophylaxis during pregnancy and the postpartum period.

Study protocol for FUTURES: Testing a web-based reproductive health education program for adolescent and young adult males with sickle cell disease.

Individuals with sickle cell disease are increasingly surviving into adulthood, many of whom have interest in future biological parenthood. Reproductive health knowledge is low among adolescent and young adult males and their caregivers. Their understanding of these topics is needed to optimize their reproductive health outcomes. As such, through collaboration with a community advisory board (adolescents and young adults with sickle cell disease and mothers of adolescent and young adult males with sickle cell disease) and digital design team, we developed a web-based sickle cell disease-focused reproductive health program entitled FUTURES to address these knowledge gaps. For phase I of this two phase feasibility and acceptability study, adolescent and young adult males and their caregivers will complete a pre- and post-program reproductive health knowledge and attitudes questionnaire to assess change in knowledge. In phase II, after learning about fertility testing as part of the FUTURES curriculum, adolescent and young adult male participants are given the option to pursue testing. The two-phase study aims to: 1) develop and test the feasibility, acceptability, and efficacy of a reproductive health web-based educational program at increasing reproductive health knowledge in male adolescent and young adult males with sickle cell disease and their caregivers, and 2) assess feasibility of fertility testing. The long-term goal is to improve reproductive and psychosocial outcomes among adolescent and young adult males with sickle cell disease.

Closing knowledge gaps among parents of children with sickle cell trait.

BACKGROUND: Despite needing to be informed about sickle cell trait (SCT) status to make informed reproductive decisions, more than 80% of adults with SCT, including parents of children with SCT who have a high prevalence of SCT, do not know their status. PROCEDURE: This was a prospective study of parents who received SCT telephone education from the state department of health and then completed SCTaware, a videoconference-administered SCT education program. The objectives were to evaluate knowledge after telephone education and explore if SCTaware closes knowledge gaps. Participants completed a demographic survey, a health literacy assessment, and reported their SCT status. They completed the Sickle Cell Trait Knowledge Assessment before receiving SCTaware, immediately after, and at follow-up visits; high knowledge was a score of 75% or higher correct. RESULTS: SCTaware and the initial surveys were completed by 61 parents; 45 completed the 6-month surveys. Only 43% of participants had high SCT knowledge after telephone education; 92% achieved high knowledge immediately after, and 84% continued with high knowledge at 6 months. Most parents reported they were aware of their SCT status after telephone education; 12 changed their response after receiving SCTaware. CONCLUSIONS: Our findings suggest that over half of parents have low SCT knowledge following telephone education, and many may be unaware of their status. SCTaware closes knowledge gaps, leads to high sustained knowledge, and is a potentially scalable tool. Future studies should refine SCTaware and determine if parents use their knowledge to inform their children and reproductive decisions.