Description of a national, multi-center registry of patients with sickle cell disease and SARS-CoV-2 infection: Data from the Pediatric COVID-19 United States Registry

Children with sickle cell disease (SCD) are at risk of complications from viral infections, including SARS-CoV-2. We present the clinical characteristics and outcomes of pediatric patients with SCD from the Pediatric COVID-19 United States Registry who developed acute COVID-19 due to SARS-CoV-2 infection (n = 259) or multisystem inflammatory syndrome in children (MIS-C; n = 4). Nearly half of hospitalized children with SCD and SARS-CoV-2 infection required supplemental oxygen, though children with SCD had fewer intensive care (ICU) admissions compared to the general pediatric and immunocompromised populations. All registry patients with both SCD and MIS-C required ICU admission. Children with SCD are at risk of severe disease with SARS-CoV-2 infection, highlighting the importance of vaccination in this vulnerable population.

Impact of Hematopoietic Cell Transplantation on Myocardial Fibrosis in Young Patients with Sickle Cell Disease

Serial cardiovascular magnetic resonance evaluation of children and young adults with sickle cell disease (SCD) who underwent hematopoietic cell transplantation (HCT) showed that the mean ECV, representing diffuse myocardial fibrosis, decreased by 3.4% from the baseline to 12-months post HCT. (NCT04362293).

Mortality in adults with sickle cell disease: Results from the sickle cell disease implementation consortium (SCDIC) registry

The cause of death in people affected by sickle cell disease (SCD) is often challenging to define as prior studies have used retrospective or administrative data for analysis. We used a prospective longitudinal registry to assess mortality and clinical co-morbidities among subjects enrolled in the Sickle Cell Disease Implementation Consortium (SCDIC) registry. At enrollment, we collected the following data: patient-reported demographics, SCD phenotype, baseline laboratory values, comorbidities, and current medications. Subjects were followed for a median of 4.7 years before the present analysis. The relationship of clinical co-morbidities (at time of enrollment) to mortality was determined using survival analysis, adjusting for SCD phenotype and gender. There was a total of 2439 people with SCD enrolled in the SCDIC registry. One hundred and twenty-eight participants (5%) died during the observation period (2017-2022). Six people died from trauma and were excluded from further analysis. Proximate cause of death was unwitnessed in 17% of the deaths, but commonest causes of death include cardiac (18%), acute chest or respiratory failure (11%), sudden unexplained death (8%). Enrollment characteristics of the individuals who died (n = 122) were compared to those of survivors (n = 2317). Several co-morbidities at enrollment increased the odds of death on univariate analysis. All co-morbidities were included in a multivariable model. After backward elimination, iron overload, pulmonary hypertension, and depression, remained statistically significant predictors of the risk of death. SCD reduces life expectancy. Improved comprehensive and supportive care to prevent end-organ damage and address comorbidities is needed for this population.

Recruitment Strategies in the Integration of Mobile Health Into Sickle Cell Disease Care to Increase Hydroxyurea Utilization Study (meSH): Multicenter Survey Study

BACKGROUND

Hydroxyurea is an evidence-based disease-modifying therapy for sickle cell disease (SCD) but is underutilized. The Integration of Mobile Health into Sickle Cell Disease Care to Increase Hydroxyurea Utilization (meSH) multicenter study leveraged mHealth to deliver targeted interventions to patients and providers. SCD studies often underenroll; and recruitment strategies in the SCD population are not widely studied. Unanticipated events can negatively impact enrollment, making it important to study strategies that ensure adequate study accrual.

OBJECTIVE

The goal of this study was to evaluate enrollment barriers and the impact of modified recruitment strategies among patients and providers in the meSH study in response to a global emergency.

METHODS

Recruitment was anticipated to last 2 months for providers and 6 months for patients. The recruitment strategies used with patients and providers, new recruitment strategies, and recruitment rates were captured and compared. To document recruitment adaptations and their reasons, study staff responsible for recruitment completed an open-ended 9-item questionnaire eliciting challenges to recruitment and strategies used. Themes were extrapolated using thematic content analysis.

RESULTS

Total enrollment across the 7 sites included 89 providers and 293 patients. The study acceptance rate was 85.5% (382/447) for both patients and providers. The reasons patients declined participation were most frequently a lack of time and interest in research, while providers mostly declined because of self-perceived high levels of SCD expertise, believing they did not need the intervention. Initially, recruitment involved an in-person invitation to participate during clinic visits (patients), staff meetings (providers), or within the office (providers). We identified several important recruitment challenges, including (1) lack of interest in research, (2) lack of human resources, (3) unavailable physical space for recruitment activities, and (4) lack of documentation to verify eligibility. Adaptive strategies were crucial to alleviate enrollment disruptions due to the COVID-19 pandemic. These included remote approaching and consenting (eg, telehealth, email, and telephone) for patients and providers. Additionally, for patients, recruitment was enriched by simplification of enrollment procedures (eg, directly approaching patients without a referral from the provider) and a multitouch method (ie, warm introductions with flyers, texts, and patient portal messages). We found that patient recruitment rates were similar between in-person and adapted (virtual with multitouch) approaches (167/200, 83.5% and 126/143, 88.1%, respectively; P=.23). However, for providers, recruitment was significantly higher for in-person vs remote recruitment (48/50, 96% and 41/54, 76%, respectively, P<.001).

CONCLUSIONS

We found that timely adaptation in recruitment strategies secured high recruitment rates using an assortment of enriched remote recruitment strategies. Flexibility in approach and reducing the burden of enrollment procedures for participants aided enrollment. It is important to continue identifying effective recruitment strategies in studies involving patients with SCD and their providers and the impact and navigation of recruitment challenges.

TRIAL REGISTRATION

ClinicalTrials.Gov NCT03380351; https://clinicaltrials.gov/study/NCT03380351.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

RR2-10.2196/16319.

Empirically derived profiles of neurocognitive functioning in youth and young adults with sickle cell disease

OBJECTIVE

Sickle cell disease (SCD) is an inherited blood disorder associated with neurocognitive deficits. In contrast to variable-centered approaches, no known research has utilized person-centered strategies to identify multidimensional patterns of neurocognitive functioning of an individual with SCD. The purpose of the present study was to create empirically derived profiles and identify predictors of neurocognitive functioning subgroups among youth and young adults with SCD.

METHODS

Individuals with SCD (N = 393, mean age 14.05 years, age range 8-24, 50.4% female/49.6% male) completed neurocognitive assessments. Latent profile analysis derived subgroups/classes of neurocognitive functioning and determined relations with demographic and medical variables.

RESULTS

Three latent classes emerged: average functioning (n = 102, 27%), low average functioning (n = 225, 60%), and exceptionally low functioning (n = 46, 12%). Older age was associated with membership in the low average and exceptionally low functioning groups (relative to the average group). Being prescribed hydroxyurea was associated with membership in the average functioning group (relative to the low average group) and absence of hydroxyurea use was associated with membership in the exceptionally low group (relative to the low average group). Lower social vulnerability was associated with membership in the average functioning group compared to the low average and exceptionally low groups.

CONCLUSIONS

Clinicians can help reduce disparities in cognitive development for individuals with SCD by promoting early treatment with hydroxyurea and implementing methods to reduce social vulnerabilities that can interfere with access to evidence-based care.

Translation, transcultural adaptation, and validation of PedsQL 3.0 Sickle Cell Disease Module into Brazilian Portuguese

INTRODUCTION

Despite the high prevalence of sickle cell disease (SCD) in Brazil, no studies have described the validation of an SCD-specific health-related quality-of-life (HRQoL) instrument in children. We validated PedsQL 3.0 Sickle Cell Disease Module (PedsQL-SCD) for Brazilian Portuguese, and cross-validated it with PedsQL 4.0 Generic Core Scale (PedsQL-GCS) in children with SCD.

METHODS

PedsQL-SCD was translated and culturally adapted using forward and reverse translations. PedsQL-SCD and PedsQL-GCS were tested in children and adolescents with SCD aged 2-18 years and their caregivers. Validity was assessed using the Pearson and intraclass correlation coefficients, and reliability measured with Cronbach's alpha.

RESULTS

PedsQL-SCD was validated in 206 children with SCD (median age 14 years, range: 8-18) and 201 caregivers. Among patients and caregivers, the mean total score for PedsQL-SCD was 65.7 and 64.1, respectively. The mean total score for PedsQL-GCS was 73.1 and 68.9 among patients and caregivers, respectively. The internal consistency for PedsQL-SCD and PedsQL-GCS was good; Cronbach's alpha coefficients ranged from .59-.93 to .64-.83 among patients and from .60-.95 to .65-.85 among caregivers, respectively. Most intercorrelations between PedsQL-SCD and PedsQL-GCS, for patients and caregivers, had medium to large effect sizes (range: .23-.63 and .27-.64, respectively). Pain and pain impact domains of PedsQL-SCD and physical dimension of PedsQL-GCS had the highest cross-correlation (.63 and .6 for patients; .63 and .64 for caregivers, respectively), confirming convergent construct validity.

CONCLUSION

PedsQL-SCD is a valid, culturally appropriate measure to assess HRQoL in children with SCD in Brazil and is well-correlated PedsQL-GCS.

Awareness, access, and communication: provider perspectives on early intervention services for children with sickle cell disease

Purpose

This study aimed to identify determinants influencing the utilization of early intervention services among young children with sickle cell disease (SCD) based on perspectives from medical and early intervention providers.

Design and methods

Early intervention and medical providers from the catchment area surrounding St. Jude Children's Research Hospital and Washington University were recruited (20 total providers). Interviews were completed over the phone and audio recorded. All interviews were transcribed verbatim, coded, and analyzed using inductive thematic analysis.

Results

Three overarching themes were identified from both groups: Awareness (e.g., lack of awareness about the EI system and SCD), Access (e.g., difficulties accessing services), and Communication (e.g., limited communication between medical and early intervention providers, and between providers and families). Although these three themes were shared by medical and early intervention providers, the differing perspectives of each produced subthemes unique to the two professional fields.

Conclusions

Early intervention services can limit the neurodevelopmental deficits experienced by young children with SCD; however, most children with SCD do not receive these services. The perspectives of early intervention and medical providers highlight several potential solutions to increase early intervention utilization among young children with SCD.

Machine learning to optimize automated RH genotyping using whole-exome sequencing data

Rh phenotype matching reduces but does not eliminate alloimmunization in patients with sickle cell disease (SCD) due to RH genetic diversity that is not distinguishable by serological typing. RH genotype matching can potentially mitigate Rh alloimmunization, but comprehensive and accessible genotyping methods are needed. We developed RHtyper as an automated algorithm to predict RH genotypes using whole-genome sequencing (WGS) data with high accuracy. Here, we adapted RHtyper for whole-exome sequencing (WES) data which are more affordable but challenged by uneven sequencing coverage and exacerbated sequencing read misalignment, resulting in uncertain prediction for 1) RHD zygosity and hybrid alleles, 2) RHCE*C versus RHCE*c alleles, 3) RHD c.1136C>T zygosity, and 4) RHCE c.48G>C zygosity. We optimized RHtyper to accurately predict RHD and RHCE genotypes using WES data by leveraging machine learning models and improved the concordance of WES with WGS predictions from 90.8% to 97.2% for RHD and 96.3 to 98.2% for RHCE among 396 patients in the Sickle Cell Clinical Research and Intervention Program (SCCRIP). In a second validation cohort with 3030 cancer survivors (15.2% Black or African Americans) from the St. Jude Lifetime Cohort Study (SJLIFE), the optimized RHtyper reached concordance rates between WES and WGS predications to 96.3% for RHD, and 94.6% for RHCE. In conclusion, machine learning improved the accuracy of RH predication from WES data. RHtyper has the potential, once implemented, to provide a precision medicine-based approach to facilitate RH genotype-matched transfusion and improve transfusion safety for patients with SCD.

Burden of employment loss and absenteeism in adults and caregivers of children with sickle cell disease

ABSTRACT

Sickle cell disease (SCD) is a genetic disorder affecting 100 000 people with an estimated annual medical cost of $3 billion in the United States; however, the economic impact on patients is not well described. We aimed to examine the indirect economic burden and test the hypothesis that socioeconomic status and greater social vulnerability risks are associated with increased absenteeism and employment loss. We surveyed adults and caregivers of children with SCD at 5 US centers from 2014 to 2021. Logistic regression models were used to examine the associations of employment loss and missed days of work with demographics and social determinants. Indirect costs were estimated by multiplying the self-reported missed days of work and job loss by 2022 average wages by the state of the participating institution. Of the 244 participants, 10.3% reported employment loss in the last 5 years, and 17.5% reported missing 10 or more days of work. Adults had 3 times more employment loss compared with caregivers of children with SCD (OR, 3.18; 95% CI, 1.12-9.01) but fewer missed days of work (OR, 0.24; 95% CI, 0.11-0.0.51). Participants who did not live with a partner reported increased employment loss (OR, 4.70; 95% CI, 1.04-21.17) and more missed days of work (OR, 4.58; 95% CI, 1.04-20.15). The estimated annual indirect economic burden was $2 266 873 ($9290 per participant). Adults with SCD and caregivers of children with SCD commonly report employment loss and missed days of work as important risk factors. The high indirect economic burden suggests that future economic evaluations of SCD should include SCD-related indirect economic burden.

Agreement between youth and caregiver report of pain and functioning in pediatric sickle cell disease: PedsQL sickle cell disease module

ABSTRACT

Pain is a primary symptom of sickle cell disease (SCD) and is often severe and chronic. To treat SCD-related pain, proper assessment of SCD pain among youth, including the degree of concordance or agreement between youth and caregiver reports of pain, is essential but has not yet been adequately evaluated. In this study, 525 youth with SCD and their parents were evaluated as part of the Sickle Cell Clinical Research and Intervention Program (SCCRIP) to examine pain rating concordance and predictors of concordance. Youth and parents completed the Pediatric Quality of Life Inventory Sickle Cell Disease module (PedsQL-SCD) to measure pain, pain interference, and pain-related constructs. Disease, clinical, and demographic variables were obtained from the SCCRIP database. Intraclass correlations demonstrated moderate-to-poor consistency between youth and caregiver reports of pain and pain interference (ICCs range from 0.17 to 0.54). Analysis of covariance and regression models found that patient age, frequency of hospitalizations and emergency department (ED) visits, economic hardship, and fetal hemoglobin levels were significantly associated with varying pain-rating agreement levels among parent proxy and child self-report pain. Concordance of pain assessments among youth with SCD and their caregivers using the PedsQL-SCD Module was moderate at best, corroborating prior research. Youth factors predicting discordance among pain-related factors included increased ED visits, older age, and female sex. Collectively, these results bolster the use of integrated pain assessments to reduce parent-child discrepancies, thereby improving the adequacy of SCD-related pain assessment and treatment.

RH genotypes and red cell alloimmunization rates in chronically transfused patients with sickle cell disease: A multisite study in the USA

BACKGROUND

Red cell alloimmunization remains a challenge for individuals with sickle cell disease (SCD) and contributes to increased risk of hemolytic transfusion reactions and associated comorbidities. Despite prophylactic serological matching for ABO, Rh, and K, red cell alloimmunization persists, in part, due to a high frequency of variant RH alleles in patients with SCD and Black blood donors.

STUDY DESIGN AND METHODS

We compared RH genotypes and rates of alloimmunization in 342 pediatric and young adult patients with SCD on chronic transfusion therapy exposed to >90,000 red cell units at five sites across the USA. Genotyping was performed with RHD and RHCE BeadChip arrays and targeted assays.

RESULTS

Prevalence of overall and Rh-specific alloimmunization varied among institutions, ranging from 5% to 41% (p = .0035) and 5%-33% (p = .0002), respectively. RH genotyping demonstrated that 33% RHD and 57% RHCE alleles were variant in this cohort. Patients with RHCE alleles encoding partial e antigens had higher rates of anti-e identified than those encoding at least one conventional e antigen (p = .0007). There was no difference in anti-D, anti-C, or anti-E formation among patients with predicted partial or altered antigen expression compared to those with conventional antigens, suggesting that variant Rh on donor cells may also stimulate alloimmunization to these antigens.

DISCUSSION

These results highlight variability in alloimmunization rates and suggest that a molecular approach to Rh antigen matching may be necessary for optimal prevention of alloimmunization given the high prevalence of variant RH alleles among both patients and Black donors.

Multicomponent Strategy Improves Human Papillomavirus Vaccination Rates Among Adolescents with Sickle Cell Disease

OBJECTIVE

To evaluate the effectiveness of a vaccine strategy bundle to increase human papillomavirus (HPV) vaccine initiation and completion in a specialty clinic setting.

STUDY DESIGN

Our Hematology clinic utilized an implementation framework from October 1, 2018, to December 31, 2019, involving nurses, nursing coordinators, and clinicians in administering the HPV vaccination series to our adolescent sickle cell sample of nearly 500 patients. The bundle included education for staff on the need for HPV vaccine administration, provider incentives, vaccines offered to patients in SCD clinics, and verification of patients' charts of vaccine completion.

RESULTS

Following the implementation of the bundle, the cumulative incidence of HPV vaccination initiation and completion improved from 28% to 46% and 7% to 49%, respectively. Both rates remained higher postimplementation as well. HPV vaccination series completion was associated with a decreased distance to the health care facility, lower state deprivation rank, and increased hospitalizations.

CONCLUSION

Our clinic's implementation strategy successfully improved vaccine completion rates among adolescents with sickle cell disease (SCD) while continuing to educate staff, patients, and families on the importance of cancer prevention among people living with SCD.

Comparative pharmacovigilance assessment of adverse events associated with the use of hydroxyurea, L-glutamine, voxelotor, and crizanlizumab in sickle cell disease

Using disproportionality analysis, this study compared the adverse events (AEs) associated with the use of the new agents (e.g., L-glutamine, voxelotor, and crizanlizumab) to the commonly used medication, hydroxyurea, in sickle cell disease. We found that the most frequent drug-related AEs observed in this real-world study were consistent with those in the HOPE (voxelotor) and SUSTAIN (crizanlizumab) trials, but the rates of AEs were lower. Our study demonstrates that the most common AEs and symptoms of an increased risk associated with the individual drugs varied by treatment. Disproportionate reporting signals of drug-related AEs may also capture information that is independent of subjective measures of patient-reported symptoms. Our study highlights the important need for facilitating patient-physician communication in routine clinical care to understand patient-reported symptoms.

Gene Therapy Versus Common Care for Eligible Individuals With Sickle Cell Disease in the United States : A Cost-Effectiveness Analysis

BACKGROUND

Sickle cell disease (SCD) and its complications contribute to high rates of morbidity and early mortality and high cost in the United States and African heritage community.

OBJECTIVE

To evaluate the cost-effectiveness of gene therapy for SCD and its value-based prices (VBPs).

DESIGN

Comparative modeling analysis across 2 independently developed simulation models (University of Washington Model for Economic Analysis of Sickle Cell Cure [UW-MEASURE] and Fred Hutchinson Institute Sickle Cell Disease Outcomes Research and Economics Model [FH-HISCORE]) using the same databases.

DATA SOURCES

Centers for Medicare & Medicaid Services claims data, 2008 to 2016; published literature.

TARGET POPULATION

Persons eligible for gene therapy.

TIME HORIZON

Lifetime.

PERSPECTIVE

U.S. health care sector and societal.

INTERVENTION

Gene therapy versus common care.

OUTCOME MEASURES

Incremental cost-effectiveness ratios (ICERs), equity-informed VBPs, and price acceptability curves.

RESULTS OF BASE-CASE ANALYSIS

At an assumed $2 million price for gene therapy, UW-MEASURE and FH-HISCORE estimated ICERs of $193 000 per QALY and $427 000 per QALY, respectively, under the health care sector perspective. Corresponding estimates from the societal perspective were $126 000 per QALY and $281 000 per QALY. The difference in results between models stemmed primarily from considering a slightly different target population and incorporating the quality-of-life (QOL) effects of splenic sequestration, priapism, and acute chest syndrome in the UW model. From a societal perspective, acceptable (>90% confidence) VBPs ranged from $1 million to $2.5 million depending on the use of alternative effective metrics or equity-informed threshold values.

RESULTS OF SENSITIVITY ANALYSIS

Results were sensitive to the costs of myeloablative conditioning before gene therapy, effect on caregiver QOL, and effect of gene therapy on long-term survival.

LIMITATION

The short-term effects of gene therapy on vaso-occlusive events were extrapolated from 1 study.

CONCLUSION

Gene therapy for SCD below a $2 million price tag is likely to be cost-effective when applying a societal perspective at an equity-informed threshold for cost-effectiveness analysis.

PRIMARY FUNDING SOURCE

National Heart, Lung, and Blood Institute.

A multilevel mHealth intervention boosts adherence to hydroxyurea in individuals with sickle cell disease

Hydroxyurea reduces sickle cell disease (SCD) complications, but medication adherence is low. We tested 2 mobile health (mHealth) interventions targeting determinants of low adherence among patients (InCharge Health) and low prescribing among providers (HU Toolbox) in a multi-center, non-randomized trial of individuals with SCD ages 15-45. We compared the percentage of days covered (PDC), labs, healthcare utilization, and self-reported pain over 24 weeks of intervention and 12 weeks post-study with a 24-week preintervention interval. We enrolled 293 patients (51% male; median age 27.5 years, 86.8% HbSS/HbSβ0-thalassemia). The mean change in PDC among 235 evaluable subjects increased (39.7% to 56.0%; P < 0.001) and sustained (39.7% to 51.4%, P < 0.001). Mean HbF increased (10.95% to 12.78%; P = 0.03). Self-reported pain frequency reduced (3.54 to 3.35 events/year; P = 0.041). InCharge Health was used ≥1 day by 199 of 235 participants (84.7% implementation; median usage: 17% study days; IQR: 4.8-45.8%). For individuals with ≥1 baseline admission for pain, admissions per 24 weeks declined from baseline through 24 weeks (1.97 to 1.48 events/patient, P = 0.0045) and weeks 25-36 (1.25 events/patient, P = 0.0015). PDC increased with app use (P < 0.001), with the greatest effect in those with private insurance (P = 0.0078), older subjects (P = 0.033), and those with lower pain interference (P = 0.0012). Of the 89 providers (49 hematologists, 36 advanced care providers, 4 unreported), only 11.2% used HU Toolbox ≥1/month on average. This use did not affect change in PDC. Tailoring mHealth solutions to address barriers to hydroxyurea adherence can potentially improve adherence and provide clinical benefits. A definitive randomized study is warranted. This trial was registered at www.clinicaltrials.gov as #NCT04080167.

Corrigendum: Academic performance of children with sickle cell disease in the United States: a meta-analysis

[This corrects the article DOI: 10.3389/fneur.2021.786065.].

Provider prescription of hydroxyurea in youth and adults with sickle cell disease: A review of prescription barriers and facilitators

Sickle cell disease (SCD) is an inherited red blood cell disorder associated with frequent painful events and organ damage. Hydroxyurea (HU) is the recommended evidence-based treatment of SCD. However, among patients eligible for HU, prescription rates are low. Utilizing a scoping review approach, we summarized and synthesized relevant findings regarding provider barriers and facilitators to the prescription of HU in youth and adults with SCD and provided suggestions for future implementation strategies to improve prescription rates. Relevant databases were searched using specified search terms. Articles reporting provider barriers and/or facilitators to prescribing HU were included. A total of 10 studies met the inclusion criteria. Common barriers to the prescription of HU identified by providers included: doubts around patients' adherence to HU and their engaging in required testing, concerns about side effects, lack of knowledge, cost and patient concerns about side effects. Facilitators to the prescription of HU included beliefs in the effectiveness of HU, provider demographics and knowledge. Findings suggest significant provider biases exist, particularly in the form of negative perceptions towards patients' ability to adhere to taking HU and engaging in the required follow-up. Improving provider knowledge and attitudes towards HU and SCD may help improve low prescription rates.

Catechol-O-methyltransferase gene (COMT) is associated with neurocognitive functioning in patients with sickle cell disease

PURPOSE

Neurocognitive impairment is a common and debilitating complication of sickle cell disease (SCD) resulting from a combination of biological and environmental factors. The catechol-O-methyltransferase (COMT) gene modulates levels of dopamine availability in the prefrontal cortex. COMT has repeatedly been implicated in the perception of pain stimuli and frequency of pain crises in patients with SCD and is known to be associated with neurocognitive functioning in the general population. The current study aimed to examine the associations of genetic variants in COMT and neurocognitive functioning in patients with SCD.

PATIENTS AND METHODS

The Sickle Cell Clinical Research and Intervention Program (SCCRIP) longitudinal cohort was used as a discovery cohort (n = 166). The genotypes for 5 SNPs (rs6269, rs4633, rs4818, rs4680, and rs165599) in COMT were extracted from whole genome sequencing data and analyzed using a dominant model. A polygenic score for COMT (PGSCOMT) integrating these 5 SNPs was analyzed as a continuous variable. The Cooperative Study of Sickle Cell Disease (CSSCD, n = 156) and the Silent Cerebral Infarction Transfusion (SIT, n = 114) Trial were used as 2 independent replication cohorts. Due to previously reported sex differences, all analyses were conducted separately in males and females. The Benjamini and Hochberg approach was used to calculate false discovery rate adjusted p-value (q-value).

RESULTS

In SCCRIP, 1 out of 5 SNPs (rs165599) was associated with IQ at q<0.05 in males but not females, and 2 other SNPs (rs4633 and rs4680) were marginally associated with sustained attention at p<0.05 in males only but did not maintain at q<0.05. PGSCOMT was negatively associated with IQ and sustained attention at p<0.05 in males only. Using 3 cohorts' data, 4 out of 5 SNPs (rs6269, rs4633, rs4680, rs165599) were associated with IQ (minimum q-value = 0.0036) at q<0.05 among male participants but not female participants. The PGSCOMT was negatively associated with IQ performance among males but not females across all cohorts.

CONCLUSION

Select COMT SNPs are associated with neurocognitive abilities in males with SCD. By identifying genetic predictors of neurocognitive performance in SCD, it may be possible to risk-stratify patients from a young age to guide implementation of early interventions.

"The project did not come to us with a solution": Perspectives of research teams on implementing a study about electronic health record-embedded individualized pain plans for emergency department treatment of vaso-occlusive episodes in adults with sickle cell disease

BACKGROUND

This study aimed to capture the implementation process of the ALIGN Study, (An individualized Pain Plan with Patient and Provider Access for Emergency Department care of Sickle Cell Disease). ALIGN aimed to embed Individualized Pain Plans in the electronic health record (E-IPP) and provide access to the plan for both adult patients with sickle cell disease (SCD) and emergency department providers when a person with SCD comes to the emergency department in vaso-occlusive crises.

METHODS

Semi-structured interviews were conducted with research teams from the 8 participating sites from the ALIGN study. Seventeen participants (principal investigators and study coordinators) shared their perspectives about the implementation of ALIGN in their sites. Data were analyzed in three phases using open coding steps adapted from grounded theory and qualitative content analysis.

RESULTS

A total of seven overarching themes were identified: (1) the E-IPP structure (location and upkeep) and collaboration with the informatics team, (2) the role of ED champion, (3) the role of research coordinators, (4) research team communication, and communication between research team and clinical team, (5) challenges with the study protocol, (6) provider feedback: addressing over-utilizers, patient mistrust, and the positive feedback about the intervention, and (7) COVID-19 and its effects on study implementation.

CONCLUSIONS

Findings from this study contribute to learning how to implement E-IPPs for adult patients with SCD in ED. The study findings highlight the importance of early engagement with different team members, a champion from the emergency department, study coordinators with different skills and enhancement of communication and trust among team members. Further recommendations are outlined for hospitals aiming to implement E-IPP for patients with SCD in ED.

Examining the influence of pain and fatigue on neurocognitive functioning in adolescents and young adults with sickle cell disease

Pain and fatigue are among the most common and impactful complications of sickle cell disease (SCD). Individuals with SCD are also more likely to have neurocognitive deficits. Previous studies have suggested that pain and fatigue might influence neurocognitive functioning in patients with SCD. However, these studies are limited by small sample sizes and inadequate measurement of cognitive performance. The present study aimed to investigate the relationship between pain and fatigue with neurocognitive functioning using performance-based measures of neurocognition. Pain and fatigue were not associated with neurocognitive performance. Implications and directions for future research are discussed.

Proinflammatory state promotes red blood cell alloimmunization in pediatric patients with sickle cell disease

We examined risk factors for red blood cell (RBC) alloimmunization in pediatric patients with sickle cell disease, focusing on the recipients' inflammatory state at the time of transfusion and anti-inflammatory role of hydroxyurea (HU). Among 471 participants, 55 (11.70%) participants were alloimmunized and formed 59 alloantibodies and 17 autoantibodies with an alloimmunization rate of 0.36 alloantibodies per 100 units. Analysis of 27 participants in whom alloantibodies were formed with specificities showed 23.8% (30/126) of units transfused during a proinflammatory event resulting in alloantibody formation compared with 2.8% (27/952) of units transfused at steady state. Therefore, transfusion during proinflammatory events increased the risk for alloimmunization (odds ratio [OR], 4.22; 95% confidence interval [CI], 1.64-10.85; P = .003). Further analysis of all the 471 participants showed that alloimmunization of patients who received episodic transfusion, mostly during proinflammatory events, was not reduced with HU therapy (OR, 6.52; 95% CI, 0.85-49.77; P = .071), HU therapy duration (OR, 1.13; 95% CI, 0.997-1.28; P = .056), or HU dose (OR, 1.06; 95% CI, 0.96-1.16; P = .242). The analysis also identified high transfusion burden (OR, 1.02; 95% CI, 1.003-1.04; P = .020) and hemoglobin S (HbSS) and HbSβ0-thalassemia genotypes (OR, 11.22, 95% CI, 1.51-83.38; P = .018) as additional risk factors for alloimmunization. In conclusion, the inflammatory state of transfusion recipients affects the risk of RBC alloimmunization, which is not modified by HU therapy. Judicious use of transfusion during proinflammatory events is critical for preventing alloimmunization.

Age-related differences in risks and outcomes of 30-day readmission in adults with sickle cell disease

BACKGROUND

Literature on 30-day readmission in adults with sickle cell disease (SCD) is limited. This study examined the overall and age-stratified rates, risk factors, and healthcare resource utilization associated with 30-day readmission in this population.

METHODS

Using the Nationwide Readmissions Database, a retrospective cohort study was conducted to identify adult patients (aged ≥ 18) with SCD in 2016. Patients were stratified by age and followed for 30 days to assess readmission following an index discharge. The primary outcome was 30-day unplanned all-cause readmission. Secondary outcomes included index hospitalization costs and readmission outcomes (e.g., time to readmission, readmission costs, and readmission lengths of stay). Separate generalized linear mixed models estimated the adjusted odds ratios (aORs) for associations of readmission with patient and hospital characteristics, overall and by age.

RESULTS

Of 15,167 adults with SCD, 2,863 (18.9%) experienced readmission. Both the rates and odds of readmission decreased with increasing age. The SCD complications vaso-occlusive crisis and end-stage renal disease (ESRD) were significantly associated with increased likelihood of readmission (p < 0.05). Age-stratified analyses demonstrated that diagnosis of depression significantly increased risk of readmission among patients aged 18-to-29 years (aOR = 1.537, 95%CI: 1.215-1.945) but not among patients of other ages. All secondary outcomes significantly differed by age (p < 0.05).

CONCLUSION

This study demonstrates that patients with SCD are at very high risk of 30-day readmission and that younger adults and those with vaso-occlusive crisis and ESRD are among those at highest risk. Multifaceted, age-specific interventions targeting individuals with SCD on disease management are needed to prevent readmissions.

CRISPR-Cas9 Editing of the HBG1 and HBG2 Promoters to Treat Sickle Cell Disease

BACKGROUND

Sickle cell disease is caused by a defect in the β-globin subunit of adult hemoglobin. Sickle hemoglobin polymerizes under hypoxic conditions, producing deformed red cells that hemolyze and cause vaso-occlusion that results in progressive organ damage and early death. Elevated fetal hemoglobin levels in red cells protect against complications of sickle cell disease. OTQ923, a clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9-edited CD34+ hematopoietic stem- and progenitor-cell (HSPC) product, has a targeted disruption of the HBG1 and HBG2 (γ-globin) gene promoters that increases fetal hemoglobin expression in red-cell progeny.

METHODS

We performed a tiling CRISPR-Cas9 screen of the HBG1 and HBG2 promoters by electroporating CD34+ cells obtained from healthy donors with Cas9 complexed with one of 72 guide RNAs, and we assessed the fraction of fetal hemoglobin-immunostaining erythroblasts (F cells) in erythroid-differentiated progeny. The gRNA resulting in the highest level of F cells (gRNA-68) was selected for clinical development. We enrolled participants with severe sickle cell disease in a multicenter, phase 1-2 clinical study to assess the safety and adverse-effect profile of OTQ923.

RESULTS

In preclinical experiments, CD34+ HSPCs (obtained from healthy donors and persons with sickle cell disease) edited with CRISPR-Cas9 and gRNA-68 had sustained on-target editing with no off-target mutations and produced high levels of fetal hemoglobin after in vitro differentiation or xenotransplantation into immunodeficient mice. In the study, three participants received autologous OTQ923 after myeloablative conditioning and were followed for 6 to 18 months. At the end of the follow-up period, all the participants had engraftment and stable induction of fetal hemoglobin (fetal hemoglobin as a percentage of total hemoglobin, 19.0 to 26.8%), with fetal hemoglobin broadly distributed in red cells (F cells as a percentage of red cells, 69.7 to 87.8%). Manifestations of sickle cell disease decreased during the follow-up period.

CONCLUSIONS

CRISPR-Cas9 disruption of the HBG1 and HBG2 gene promoters was an effective strategy for induction of fetal hemoglobin. Infusion of autologous OTQ923 into three participants with severe sickle cell disease resulted in sustained induction of red-cell fetal hemoglobin and clinical improvement in disease severity. (Funded by Novartis Pharmaceuticals; ClinicalTrials.gov number, NCT04443907.).

Preliminary construct validity of patient-reported outcomes to assess chronic pain in adults with sickle cell disease

Chronic pain affects 30% to 40% of individuals with sickle cell disease (SCD) and impairs patient functioning. Clinically meaningful, practical, and valid assessment tools for investigation, evaluation, and management of chronic pain are limited, representing a barrier for advancing SCD care. We sought to determine whether patient-reported outcomes (PROs) show preliminary construct validity in identifying individuals with SCD who were a priori defined as suggestive of having chronic pain based on previously published criteria. All individuals completed the Patient-Reported Outcomes Measurement Information System (PROMIS) domains: pain interference, pain behavior, pain quality (nociceptive, neuropathic), fatigue, sleep disturbance, depression, and anxiety; the Adult Sickle Cell Quality of Life Measurement Information System (ASCQ-Me) domains: pain impact and emotional impact; and the painDETECT questionnaire. Thirty-three adults living with SCD were enrolled, and 42.4% had chronic pain. Pain-related PROs scores distinctly differentiated individuals with chronic pain from those without. Individuals with chronic pain had significantly worse pain-related PROs scores: PROMIS pain interference (64.2 vs 54.3), PROMIS pain behavior (63.2 vs 50), and ASCQ-Me pain impact (42.9 vs 53.2). According to published PROMIS clinical cut scores for the pain-related domains, individuals with chronic pain were categorized as having moderate impairment, whereas those without chronic pain had mild or no impairment. Individuals with chronic pain had PRO pain features consistent with neuropathic pain and worse scores in fatigue, depression, sleep disturbance, and emotional impact. Pain-related PROs show preliminary construct validity in differentiating individuals with and without chronic SCD pain and could be used as valuable tools for research and clinical monitoring of chronic pain.

Attitudes toward COVID-19 vaccine among pediatric patients with sickle cell disease and their caregivers

OBJECTIVE

To evaluate attitudes toward vaccination and vaccine uptake regarding coronavirus disease 2019 (COVID-19) among pediatric patients with sickle cell disease (SCD) and their caregivers.

PROCEDURE

Adolescent patients and caregivers of children with SCD were surveyed during routine clinic visits; we then conducted a logistic regression analysis to understand differences in vaccine status, while qualitative responses were coded thematically.

RESULTS

Among respondents, the overall vaccination rate among adolescents and caregivers was 49% and 52%, respectively. Among the unvaccinated, 60% and 68% of adolescents and caregivers, respectively, preferred to remain unvaccinated, most commonly due to lack of perceived personal benefit from vaccination or mistrust in the vaccine. Multivariate logistic regression analysis showed that child's age (odds ratio [OR] = 1.1, 95% confidence interval [CI]: 1.0-1.2, p < .01) and caregiver education (measured by the Economic Hardship Index [EHI] score, OR = 0.76, 95% CI: 0.74-0.78, p < .05) were independent predictors of getting vaccinated.

CONCLUSION

Despite the increased risk of severe illness due to COVID-19 in patients with SCD, vaccine hesitancy remains high in this population of families whose children have SCD. Fortunately, the reasons cited for deferring vaccination among those who are unvaccinated were largely due to barriers that may be overcome with quality communication around the utility of the vaccine and information about vaccine safety.

Examining Mental Health, Education, Employment, and Pain in Sickle Cell Disease

Importance

Pain related to sickle cell disease (SCD) is complex and associated with social determinants of health. Emotional and stress-related effects of SCD impact daily quality of life and the frequency and severity of pain.

Objective

To explore the association of educational attainment, employment status, and mental health with pain episode frequency and severity among individuals with SCD.

Design, Setting, and Participants

This is a cross-sectional analysis of patient registry data collected at baseline (2017-2018) from patients treated at 8 sites of the US Sickle Cell Disease Implementation Consortium. Data analysis was performed from September 2020 to March 2022.

Main Outcomes and Measures

Electronic medical record abstraction and a participant survey provided demographic data, mental health diagnosis, and Adult Sickle Cell Quality of Life Measurement Information System pain scores. Multivariable regression was used to examine the associations of education, employment, and mental health with the main outcomes (pain frequency and pain severity).

Results

The study enrolled a total of 2264 participants aged 15 to 45 years (mean [SD] age, 27.9 [7.9] years; 1272 female participants [56.2%]) with SCD. Nearly one-half of the participant sample reported taking daily pain medication (1057 participants [47.0%]) and/or hydroxyurea use (1091 participants [49.2%]), 627 participants (28.0%) received regular blood transfusion, 457 (20.0%) had a depression diagnosis confirmed by medical record abstraction, 1789 (79.8%) reported severe pain (rated most recent pain crises as ≥7 out of 10), and 1078 (47.8%) reported more than 4 pain episodes in the prior 12 months. The mean (SD) pain frequency and severity t scores for the sample were 48.6 (11.4) and 50.3 (10.1), respectively. Educational attainment and income were not associated with increased pain frequency or severity. Unemployment (β, 2.13; 95% CI, 0.99 to 3.23; P < .001) and female sex (β, 1.78; 95% CI, 0.80 to 2.76; P < .001) were associated with increased pain frequency. Age younger than 18 years was inversely associated with pain frequency (β, -5.72; 95% CI, -7.72 to -3.72; P < .001) and pain severity (β, 5.10; 95% CI, -6.70 to -3.51; P < .001). Depression was associated with increased pain frequency (β, 2.18; 95% CI, 1.04 to 3.31; P < .001) but not pain severity. Hydroxyurea use was associated with increased pain severity (β, 1.36; 95% CI, 0.47 to 2.24; P = .003), and daily use of pain medication was associated with both increased pain frequency (β, 6.29; 95% CI, 5.28 to 7.31; P < .001) and pain severity (β, 2.87; 95% CI, 1.95 to 3.80; P < .001).

Conclusions and Relevance

These findings suggest that employment status, sex, age, and depression are associated with pain frequency among patients with SCD. Depression screening for these patients is warranted, especially among those experiencing higher pain frequency and severity. Comprehensive treatment and pain reduction must consider the full experiences of patients with SCD, including impacts on mental health.

Health literacy correlates with abbreviated full-scale IQ in adolescent and young adults with sickle cell disease

INTRODUCTION

Sickle cell disease (SCD) is a chronic condition with progressive neurocognitive deficits. Health literacy (HL) is essential during adolescence and young adulthood, as the transition to adult care requires healthcare decisions. HL is known to be low in SCD; however, relation between general cognitive ability and HL has not been investigated.

METHODS

This cross-sectional study included adolescent and yound adults (AYAs) with SCD from two institutions. Logistic regression measured the association between HL, measured by the Newest Vital Sign tool, and general cognitive ability, measured with abbreviated full-scale intelligence quotient (FSIQ) on the Wechsler Abbreviated Scale of Intelligence.

RESULTS

Our cohort contained 93 participants at two sites: 47 (51%) at Memphis, TN and 46 (49%) at St. Louis, MO, ranging from ages 15-45 years (mean = 21 years) and with a majority (70%) possessing a high school education or greater. Only 40/93 participants (43%) had adequate HL. Lower abbreviated FSIQ (p < .0001) and younger age at assessment (p = .0003) were associated with inadequate HL. For every standard score point increase in abbreviated FSIQ, the odds of having adequate HL compared to limited or possibly limited HL increase by 1.142 (95% confidence interval [CI]: 1.019-1.322) and 1.116 (95% CI: 1.045-1.209), respectively, after adjusting for age, institution, income, and educational attainment.

CONCLUSIONS

Understanding and addressing HL is imperative in improving self-management and health outcomes. Among AYA with SCD, low HL was prevalent and influenced by abbreviated FSIQ. Routine screening for neurocognitive deficits and HL should be performed to guide development of interventions to adapt to the HL of AYA with SCD.

Social determinants of neurocognitive and academic performance in sickle cell disease

BACKGROUND

Sickle cell disease (SCD) is associated with poor neurocognitive outcomes due to biomedical and psychosocial factors. The aims of this study were to investigate associations between household and neighborhood socioeconomic status (SES) with cognitive and academic outcomes in SCD and to determine if these relationships were modified by sickle genotype, fetal hemoglobin, or age.

PROCEDURE

We prospectively recruited patients to complete a battery of neurocognitive and academic measures. Household SES was measured using the Barratt Simplified Measure of Social Status, a composite index of parent education and occupation. The Social Vulnerability Index was used to classify individuals based on social vulnerabilities at the neighborhood level.

RESULTS

Overall, 299 patients between the ages of 4 and 18 (mean = 11.4, standard deviation = 4.3) years diagnosed with SCD (57% SS/SB0 -thalassemia) completed testing. Stepwise multivariate models demonstrated that patients with low social vulnerability (i.e., high SES) at the neighborhood level displayed intelligence and math scores that were 4.70 and 7.64 points higher than those living in areas with moderate social vulnerability, respectively (p < .05). Reading performance did not differ based on neighborhood SES; however, the effect of neighborhood SES was dependent on age, such that older participants living in neighborhoods with moderate or high levels of social vulnerability displayed poorer reading scores than those with low social vulnerability (p < .05).

CONCLUSIONS

This study identified patients with SCD at higher risk of poor academic performance based on SES. Interventions addressing academic difficulties should be offered to all children with SCD, but should be emergently offered to this subpopulation.

Infertility and treatment-seeking practices among females and males with sickle cell disease in the Sickle Cell Disease Implementation Consortium registry

OBJECTIVE

To describe the prevalence of infertility and infertility treatment seeking among people enrolled in the Sickle Cell Disease Implementation Consortium (SCDIC) registry and identify sociodemographic and clinical correlates of infertility.

DESIGN

Cross-sectional.

PARTICIPANTS

The study population included 2108 women and men (≥18 years of age) enrolled in the SCDIC registry who completed the fertility questionnaire.

RESULTS

All participants who completed the infertility-specific questions were included in the analysis (1224 females; 884 males). Of these, 16.9% of males and 23.7% of females reported infertility, in contrast to rates in the general population (12% of males; 11% of females). Only 22.8% of this subgroup had sought a fertility consultation; of these, 41% received infertility testing and 58% received advice, yet only a few received specific treatment: ovulation medication (19.1%), fallopian tubal surgery (4.8%), other female treatment (17.5%), varicocelectomy (8.1%), or other male treatment (10.8%). Increasing age, employment status, and interaction between gender and single marital status are associated with reported infertility. We did not observe differences between groups relative to sickle cell disease (SCD) genotype, a broad category of self-reported hydroxyurea use any time during life, type of medical insurance, income, or education.

CONCLUSION

To our knowledge, this is the first study to examine self-reported identification of and treatment for infertility among a large sample of people with SCD. These findings suggest that (a) infertility occurs at a higher rate, but fertility care treatment seeking is less frequent than in the general public; and (b) sociodemographic and clinical differences between individuals who report experiencing infertility and those who do not did not emerge in this study.

Gene therapy in sickle cell disease: Attitudes and informational needs of patients and caregivers

BACKGROUND

Sickle cell disease (SCD) is an inherited blood disorder that results in serious morbidity and early mortality. Novel therapies for SCD, most notably genetic therapies (GTs) and HLA-mismatched donor hematopoietic cell transplantation, are in clinical trials. While potentially curative, these interventions are some of the most intensive treatments for SCD and are associated with serious and life-altering side effects, which may manifest several years after treatment. Little is known about knowledge, beliefs, and attitudes of individuals with SCD, or their caregivers, toward existing and these emerging therapies.

METHODS

Patients with SCD at least 13 years of age (n = 66) and caregivers (n = 38) were surveyed about knowledge, attitudes, and beliefs surrounding treatments for SCD.

RESULTS

Only 4.8% felt "extremely knowledgeable" about GT for SCD while the majority (63.4%) reported little knowledge. Overall, health literacy was low among respondents. Most respondents had a neutral attitude regarding the safety of GT for SCD, and whether it was a good treatment for the disorder (56.7% and 58.6%, respectively). Only a few respondents endorsed the idea that GT was "unsafe" or "not a good treatment" (5.8% and 4.8%, respectively). There was an association between increasing knowledge about GT and agreement that it is safe (p = .012) and a good treatment for SCD (p = .031).

CONCLUSIONS

Given that very few patients with SCD feel knowledgeable about GT and a majority have neutral feelings about the safety and utility of this new approach, culturally appropriate patient-centered education is urgently needed as these treatments get regulatory approval and proceed to the clinic.

Longitudinal effect of disease-modifying therapy on left ventricular diastolic function in children with sickle cell anemia

Cardiac abnormalities seen in sickle cell anemia (SCA) include diastolic dysfunction, which has been shown to be associated with high morbidity and early mortality. The effect of disease-modifying therapies (DMT) on diastolic dysfunction is poorly understood. We prospectively evaluated the effects of hydroxyurea and monthly erythrocyte transfusions on diastolic function parameters over 2 years. A total of 204 subjects with HbSS or HbSβ0-thalassemia (mean age 11 ± 3.7 years), unselected for disease severity, had diastolic function assessed with surveillance echocardiograms twice, 2 years apart. During this 2-year observation period, 112 participants received DMTs (hydroxyurea, n = 72, monthly erythrocyte transfusions, n = 40), 34 initiated hydroxyurea, and 58 did not receive any DMT. The entire cohort showed an increase in left atrial volume index (LAVi) of 3.40 ± 10.86 mL/m2, p = .001 over 2 years. This increase in LAVi was independently associated with anemia, high baseline E/e' or LV dilation. Individuals not exposed to DMT were younger (mean age 8.8 ± 2.9 years), but at baseline their prevalence of abnormal diastolic parameters was similar to that of the DMT-exposed participants who were older (mean age 12 ± 3.8 years). Participants on DMTs saw no improvement in diastolic function over the study period. In fact, participants on hydroxyurea saw a possible worsening in diastolic parameters (14% increase in LAVi and ~5% decrease in septal e') but also a ~9% decrease in fetal hemoglobin (HbF) levels. Further studies are needed to evaluate if exposure to DMT for a longer duration or achieving higher HbF might be beneficial in alleviating diastolic dysfunction.

Characterising the prevalence of overweight and obese status among adults with sickle cell disease

Individuals with sickle cell disease (SCD) have historically been considered underweight. Despite increasing body mass index (BMI) in the general population, the prevalence of overweight and obese status remains unclear in the adult SCD population. Our primary aim was to determine the prevalence of overweight and obese status and to identify associations between BMI, demographic, and clinical characteristics. We conducted an analysis of abstracted electronic health record data and patient-reported outcomes from the Sickle Cell Disease Implementation Consortium registry; individuals aged 20-45 years were included. The median (interquartile range) BMI for the 1664 adults in this analysis was 23.9 (21.1-28) kg/m2 . In this cohort, 42.9% had a BMI of >25 kg/m2 (Centers for Disease Control and Prevention definition of overweight/obese). In multivariable analysis, higher odds of being overweight or obese were associated with female gender, older age, college education, private insurance, and hypertension diagnosis. Higher odds of a BMI of >25 kg/m2 were observed in individuals with HbSC or HbSβ+ thalassaemia regardless of hydroxycarbamide (hydroxyurea) exposure (odds ratio [OR] 3.4, p < 0.0001) and HbSS or HbSβ0 thalassaemia exposed to hydroxycarbamide (OR 1.6, p = 0.0003) compared to those with HbSS or HbSβ0 thalassaemia with no hydroxycarbamide exposure. These data highlight the importance of early identification, prevention, and intervention for increasing BMI to reduce obesity-related complications that may impact SCD-related complications.

Working memory and school readiness in preschool children with sickle cell disease compared to demographically matched controls

Children diagnosed with sickle cell disease (SCD) are at risk of the development of neurobehavioural problems early in life. Specific impairments in executive function skills, including working memory, have been documented in school-aged children with SCD. These executive skills are known to strongly contribute to early academic skills and preparedness for entering kindergarten. This study examined working memory and school readiness in preschool children with SCD compared to a healthy control group matched for race, sex and parent education. A total of 84 patients diagnosed with SCD (61.9% haemoglobin [Hb]SS/HbSβ0 -thalassaemia) and 168 controls completed testing. The mean (SD) ages of patients and controls at testing were 4.53 (0.38) and 4.44 (0.65) years respectively. The SCD group performed worse than controls on measures of executive function, working memory and school readiness (p < 0.01; Cohen's D range: 0.32-0.39). Measures of working memory were associated with school readiness after accounting for early adaptive development. Multiple linear regression models among patients diagnosed with SCD revealed that college education of the primary caregiver was positively associated with school readiness (p < 0.001) after controlling for sex, genotype, age and early adaptive development. These results highlight the need to implement school readiness interventions in young children diagnosed with SCD emphasising executive function skills.

Sickle cell disease and social determinants of health: A scoping review

Social determinants of health (SDoH) may impact outcomes in sickle cell disease (SCD). We conducted a comprehensive literature review of five electronic databases to elucidate the relationship between SDoH and SCD, and identify gaps in the literature. Our search yielded 59 articles, which we organized into five SDoH areas: Neighborhood and Built Environment, Health and Healthcare, Social and Community Context, Education, and Economic Stability. We found that social determinants, such as access to healthcare, were inconsistently evaluated. Improved recognition and understanding of SDoH should enhance the development of programs that directly address its detrimental effects on patients with SCD.

Internalizing Symptoms in Adolescents With Sickle Cell Disease

OBJECTIVE

Sickle cell disease (SCD) is a genetic blood disorder that may affect patients' mood and behavior. However, measuring the prevalence of internalizing symptoms (anxiety and depression) in patients with SCD has been elusive. We assessed internalizing symptoms in adolescents with SCD to evaluate prevalence and to test whether neurocognitive performance and frequency of pain-related episodes were associated with internalizing concerns.

METHODS

One hundred eighty-five patients (57% HbSS/HbSß0-thalassemia, 43% HbSC/HbSß+-thalassemia), ages 12-18 years, received a neuropsychological evaluation as a part of a larger cohort study. Internalizing symptoms were measured using the Behavior Assessment System for Children, Second or Third Edition. Scores on the depression and anxiety scales were compared to normative values using Wilcoxon signed rank test. Spearman correlations examined associations between neurocognitive performances and internalizing symptoms. Robust multivariable regression models measured associations between internalizing symptoms and age, sex, sickle genotype, total hemoglobin, fetal hemoglobin, socioeconomic status, and frequency of pain episodes.

RESULTS

Parent- and self-reported ratings of internalizing symptoms were not elevated compared to normative expectations. Overall, 1.8% and 6.3% of the sample displayed clinically elevated symptoms of anxiety and depression based on self-report, respectively. There were no associations between internalizing symptoms and neurocognitive performance (all p > .05). In multivariable analyses, the frequency of pain episodes was positively associated with self-reported anxiety (p = .006) and parent-reported depressive symptoms (p = .017).

CONCLUSIONS

Adolescents with SCD do not report elevated internalizing symptoms compared to normative expectations. Further research is needed to examine the trajectory of internalizing symptoms and the bidirectional relationship between pain and psychosocial functioning in SCD.

Consensus definition of essential, optimal, and suggested components of a pediatric sickle cell disease center

Sickle cell disease (SCD) requires coordinated, specialized medical care for optimal outcomes. There are no United States (US) guidelines that define a pediatric comprehensive SCD program. We report a modified Delphi consensus-seeking process to determine essential, optimal, and suggested elements of a comprehensive pediatric SCD center. Nineteen pediatric SCD specialists participated from the US. Consensus was predefined as 2/3 agreement on each element's categorization. Twenty-six elements were considered essential (required for guideline-based SCD care), 10 were optimal (recommended but not required), and five were suggested. This work lays the foundation for a formal recognition process of pediatric comprehensive SCD centers.

Assessment of transition readiness to predict health care utilization during transition to adult care in sickle cell disease

BACKGROUND

Transition-age patients with sickle cell disease (SCD) are at risk for poor outcomes associated with incomplete transition readiness and neurocognitive deficits. Study objectives were to: 1) test if a SCD-specific measure of self-management skills was associated with transition outcomes and 2) evaluate if caregiver-reported executive functioning was associated with self-management skills and transition outcomes among youth with SCD.

RESEARCH DESIGN AND METHODS

Youth/caregivers were selected from a longitudinal cohort study. Caregivers completed the Behavior Rating Inventory of Executive Function (BRIEF); caregivers and youth completed the Self-Management Skills Checklist (SMSC) at a median age of 16.8 ± 0.6 years. Non-parametric tests compared SMSC and transition outcomes. Regression assessed the incremental validity of SMSC in predicting transition outcomes.

RESULTS

In total, 95 participants (54% male, 55% severe genotype) completed the SMSC assessment. Most participants (87%) transferred to adult care within six months and 87% were retained for at least 12 months. BRIEF and caregiver-reported SMSC assessments were weakly, negatively correlated (ρ = -0.25, p = 0.0392) but were not significant in predicting transition outcomes (p > 0.05).

CONCLUSIONS

The SMSC and executive function did not predict adult care engagement. Development of readiness assessments that predict care engagement and reflect self-efficacy is important for monitoring transition-aged patients with SCD.

Neurocognitive functioning in children with sickle cell anemia and history of abnormal transcranial doppler ultrasonography

BACKGROUND

Transcranial doppler (TCD) ultrasonography can be used to identify stroke risk in children with sickle cell anemia. Previous studies have reported mixed findings on neurocognitive outcomes in children with elevated TCD. This study examined associations between TCD velocity and neurocognitive outcomes in children and adolescents without prior history of stroke.

PROCEDURE

Participants were selected from the Sickle Cell Clinical Research Intervention Program cohort. The highest recorded mean maximum TCD velocity was selected for analysis, along with participant's most recent data from serial neurocognitive surveillance.

RESULTS

A total of 200 children with sickle cell anemia completed neurocognitive testing (109 males, 91 females; mean age 12.7 years [SD = 3.56]). Most participants were prescribed hydroxyurea (72%) at the time of neurocognitive testing and nearly 16% had a history of chronic transfusions prior to neurocognitive evaluation. Mean age at time of highest TCD value was 6.6 years (SD = 2.5) and 13.5% of screenings were abnormal (≥200 cm/s). Mean interval between TCD and most recent neurocognitive evaluation was 6.1 years (±3.5). There were no significant differences in the interval between TCD and neurocognitive testing across normal, conditional, and abnormal groups. Maximum TCD velocity was not significantly associated with neurocognitive outcomes in multivariate models.

CONCLUSIONS

History of elevated TCD in the absence of overt stroke should not be considered a risk factor for poor neurocognitive outcomes in children and adolescents with sickle cell anemia on modern disease-modifying therapy.

Impact of the COVID-19 Pandemic on the Implementation of Mobile Health to Improve the Uptake of Hydroxyurea in Patients With Sickle Cell Disease: Mixed Methods Study

BACKGROUND

Hydroxyurea therapy is effective for reducing complications related to sickle cell disease (SCD) and is recommended by National Health Lung and Blood Institute care guidelines. However, hydroxyurea is underutilized, and adherence is suboptimal. We wanted to test a multilevel mobile health (mHealth) intervention to increase hydroxyurea adherence among patients and improve prescribing among providers in a multicenter clinical trial. In the first 2 study sites, participants were exposed to the early phases of the COVID-19 pandemic, which included disruption to their regular SCD care.

OBJECTIVE

We aimed to describe the impact of the COVID-19 pandemic on the implementation of an mHealth behavioral intervention for improving hydroxyurea adherence among patients with SCD.

METHODS

The first 2 sites initiated enrollment 3 months prior to the start of the pandemic (November 2019 to March 2020). During implementation, site A clinics shut down for 2 months and site B clinics shut down for 9 months. We used the reach, effectiveness, adoption, implementation, and maintenance (RE-AIM) framework to evaluate the implementation and effectiveness of the intervention. mHealth implementation was assessed based on patients' daily app use. Adherence to hydroxyurea was calculated as the proportion of days covered (PDC) from prescription records over the first 12 and 24 weeks after implementation. A linear model examined the relationship between app usage and PDC change, adjusting for baseline PDC, lockdown duration, and site. We conducted semistructured interviews with patients, health care providers, administrators, and research staff to identify factors associated with mHealth implementation and effectiveness. We used a mixed methods approach to investigate the convergence of qualitative and quantitative findings.

RESULTS

The percentage of patients accessing the app decreased after March 15, 2020 from 86% (n=55) to 70% (n=45). The overall mean PDC increase from baseline to week 12 was 4.5% (P=.32) and to week 24 was 1.5% (P=.70). The mean PDC change was greater at site A (12 weeks: 20.9%; P=.003; 24 weeks: 16.7%; P=.01) than site B (12 weeks: -8.2%; P=.14; 24 weeks: -10.3%; P=.02). After adjustment, PDC change was 13.8% greater in those with increased app use after March 15, 2020. Interview findings indicated that site B's closure during COVID-19 had a greater impact, but almost all patients reported that the InCharge Health app helped support more consistent medication use.

CONCLUSIONS

We found significant impacts of the early clinic lockdowns, which reduced implementation of the mHealth intervention and led to reduced patient adherence to hydroxyurea. However, disruptions were lower among participants who experienced shorter clinic lockdowns and were associated with higher hydroxyurea adherence. Investigation of added strategies to mitigate the effects of care interruptions during major emergencies (eg, patient coaching and health navigation) may "insulate" the implementation of interventions to increase medication adherence.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04080167; https://clinicaltrials.gov/ct2/show/NCT04080167.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

RR2-10.2196/16319.

Functional Outcomes for Children, Adolescents, and Young Adults with Osteonecrosis following Hip Core Decompression

Background

Patients with pediatric leukemia and sickle cell disease are at risk for developing osteonecrosis (ON), a disease that can result in pain, loss of function, and disability. Hip core decompression surgery is an option aimed to prevent femoral head collapse and avoid future arthroplasty.

Objective

Describe functional outcomes and gait quality among a young population with hip ON before and after hip core decompression.

Methods

Study included participants with hip ON secondary to treatment for hematologic malignancy or sickle cell disease, between 8 and 29 years old, requiring hip core decompression surgery. At one-year follow-up, 13 participants (9 male, median age 17 years) completed the Functional Mobility Assessment (FMA), range of motion, and GAITRite® testing.

Results

Participants demonstrated improved mobility and endurance on the FMA at 1-year post-operatively compared to pre-operatively, with higher scores for time on the Timed Up and Go (mean FMA score = 2.92 [SD = 1.32] vs. 2.07 [SD = 1.70]), time on the Timed Up and Down Stairs (3.69 [0.85] vs. 2.92 [1.66]), and 9-Minute Walk Test scores for distance walked (2.69 [0.63] vs. 2.23 [0.93]) and heart rate (4.54 [0.66] vs. 3.31 [1.38]). GAITRite® analysis also showed improvements in many gait parameters at one-year follow-up.

Limitations

Cancer treatment complications other than ON could have contributed to results, not all eligible participants agreed to participate, and follow-up was only one year.

Conclusions

Young patients with hip ON demonstrated improvements in functional mobility, endurance, and gait quality one year following hip core decompression.

Enuresis and Hyperfiltration in Children With Sickle Cell Disease

Nocturnal enuresis is a common symptom in children with sickle cell disease (SCD). Risk factors for development of enuresis are currently unknown. An early manifestation of SCD-associated kidney damage is glomerular hyperfiltration. We test the hypothesis that in a pediatric SCD cohort, individuals with hyperfiltration are more likely to have nocturnal enuresis when compared to children without hyperfiltration. To assess the relationship between nocturnal enuresis and hyperfiltration, we retrospectively evaluated children with SCD enrolled in the Evaluation of Nocturnal Enuresis and Barriers to Treatment among Pediatric Patients with SCD study and prospectively identified children who reported nocturnal enuresis and were enrolled in the longitudinal cohort study Sickle Cell Clinical Research and Intervention Program. Nocturnal enuresis occurred in 46.5% of Pediatric Patients with Sickle Cell Disease participants and was more frequent in participants with HbSS/HbSβ 0 thalassemia and in male participants. We did not identify an association between hyperfiltration from 3 to 5 years of age with the later development of enuresis. Severe SCD genotypes and male sex were associated with nocturnal enuresis after age 5 years. We could not identify additional renal or hematologic predictors associated with the diagnosis of nocturnal enuresis. Future studies should incorporate nonrenal risk factors into studies that predict development of enuresis.

Application of validated mapping algorithms between generic PedsQL scores and utility values to individuals with sickle cell disease

PURPOSE

There is a paucity of empirically estimated health state utility (HSU) values to estimate health-related quality of life among individuals with sickle cell disease (SCD). This study aims to map the Pediatric Quality of Life Inventory generic core scales (PedsQL GCS) to HSUs for children and adolescents with SCD in the United States, using published algorithms, and to assess the construct validity of these HSUs against SCD-specific PedsQL scores.

METHODS

We used the published mapping algorithms identified in four published articles, in which the PedsQL GCS was mapped to either the EuroQol-5 Dimension 3-Level, Youth Version or the Child Health Utility 9-Dimension to obtain HSUs. We employed the algorithms to calculate HSUs for a sample of children and adolescents from the Sickle Cell Clinical Research and Intervention Program. To assess the construct validity of the mapped HSUs in SCD patients, we computed Spearman's correlation coefficient comparing the HSUs with the PedsQL SCD total score and separately with each PedsQL SCD dimension-specific score.

RESULTS

The mean mapped HSU across published algorithms was 0.792 (95% CI: 0.782-0.801). It was significantly higher among children aged 5-12 years than children aged 13-17 years. The Spearman's correlation coefficient for HSUs versus PedsQL SCD total scores was 0.64 (95% CI: 0.57-0.71). Correlations ranged from 0.40 (95% CI: 0.32-0.48) to 0.60 (95% CI: 0.54-0.66) for HSUs versus PedsQL SCD dimension-specific scores.

CONCLUSIONS

The existing mapping algorithms show acceptable construct validity in children and adolescents with SCD. Additional algorithms are needed for adults and for specific SCD comorbidities.

Hypothesis: Low Vitamin A and D Levels Worsen Clinical Outcomes When Children with Sickle Cell Disease Encounter Parvovirus B19

Human parvovirus B19 causes life-threatening anemia due to transient red cell aplasia (TRCA) in individuals with sickle cell disease (SCD). Children with SCD experiencing profound anemia during TRCA often require red blood cell transfusions and hospitalization. The prevalence of vitamin deficiencies in SCD is high and deficiencies are associated with respiratory and pain symptoms, but the effects of vitamins on acute infection with parvovirus B19 remain unclear. We performed a clinical study in which 20 SCD patients hospitalized with parvovirus B19 infections (Day 0) were monitored over a 120-day time course to query relationships between vitamins A and D and clinical outcomes. There were significant negative correlations between Day 0 vitamin levels and disease consequences (e.g., red blood cell transfusion requirements, inflammatory cytokines). There were significant positive correlations (i) between Day 0 vitamins and peak virus-specific antibodies in nasal wash, and (ii) between Day 0 virus-specific serum plus nasal wash antibodies and absolute reticulocyte counts. There was a significant negative correlation between Day 0 virus-specific serum antibodies and virus loads. To explain the results, we propose circular and complex mechanisms. Low baseline vitamin levels may weaken virus-specific immune responses to permit virus amplification and reticulocyte loss; consequent damage may further reduce vitamin levels and virus-specific immunity. While the complex benefits of vitamins are not fully understood, we propose that maintenance of replete vitamin A and D levels in children with SCD will serve as prophylaxis against parvovirus B19-induced TRCA complications.