Neurocognitive functioning in symptomatic adults with sickle cell disease: A description and comparison with unaffected siblings

Longitudinal neurocognitive effects of nonmyeloablative hematopoietic stem cell transplant among older adolescents and adults with sickle cell disease: A description and comparison with sibling donors

Sickle cell disease (SCD) is associated with increased risk of neurocognitive deficits. However, whether functioning changes following nonmyeloablative hematopoietic stem cell transplant (HSCT) remains unclear. This study aimed to examine changes in neuropsychological functioning pre- to post-transplant among patients with SCD and compare patients and siblings. Adults with SCD (n = 47; Mage = 31.8 ± 8.9) and their sibling stem cell donors (n = 22; Mage = 30.5± 9.2) enrolled on a nonmyeloablative HCST protocol completed cognitive and patient-reported outcome assessments at baseline and 12 months post-transplant. Path analyses were used to assess associations between pre-transplant variables and sibling/patient group status and post-transplant function. Mean patient cognitive scores were average at both timepoints. Patient processing speed and somatic complaints improved from baseline to follow-up. Baseline performance predicted follow-up performance across cognitive variables; patient/sibling status predicted follow-up performance on some processing speed measures. Results suggest that patients with SCD demonstrate slower processing speed than siblings. Processing speed increased pre- to post-HSCT among patients and siblings, and on some measures patients demonstrated greater improvement. Thus, HSCT may improve processing speed in patients, although further confirmation is needed. Findings provide promising evidence that neurocognitive functioning remains stable without detrimental effects from pre- to 12-months post nonmyeloablative HSCT in individuals with SCD.

Organ function indications and potential improvements following curative therapy for sickle cell disease

Curative therapies for sickle cell disease include allogeneic hematopoietic stem cell transplantation (HSCT) and gene-modified autologous stem cell transplantation. HSCT has been used for 30 years with success measured by engraftment, symptom control, graft-vs-host disease (GVHD) risk, organ toxicity, and immune reconstitution. While human leukocyte antigen-matched sibling donor (MSD) transplants have excellent outcomes, alternate donor transplants (unrelated/haploidentical) are just beginning to overcome GVHD and engraftment hurdles to match MSD. Gene therapy, a newly developed treatment, is undergoing careful evaluation in many trials with varying approaches. The risk/benefit ratio to the patient in relation to outcomes, toxicities, and mortality risk drives eligibility for curative interventions. Consequently, eligibility criteria for MSD transplants can be less stringent, especially in the young. Posttransplant outcome analysis after the "cure" with respect to organ function recovery is essential. While established damage such as stroke is irreversible, transplant can help stabilize (pulmonary function), prevent further deterioration (stroke), improve (neurocognition), and protect unaffected organs. Tracking organ functions postintervention uniformly between clinical trials and for adequate duration is essential to answer safety and efficacy questions related to curative therapies. Age-appropriate application/outcome analyses of such therapies will be the ultimate goal in overcoming this disease.

Factors associated with young adult engagement with a web-based sickle cell reproductive health intervention

Objective

To determine the factors predicting the engagement of young adults who have sickle cell disease (SCD) or sickle cell trait (SCT) with an online reproductive health education intervention and engagement effects on knowledge.

Methods

The cross-sectional study included 167 participants who completed the web-based intervention either face-to-face (F2F) or online delivery (OL). Measures include: time used relative to length of the intervention narration and media (engagement) and the SCKnowIQ questionnaire. Ordinal regression was conducted.

Results

The sample mean age was 26-years (SD=5), 68% were female, 54% had SCD, and 68% were in the F2F group. Adjusting for age, partner sickle cell status, marital status, and education, participants who were female (p=.003), had SCD (p=.018), or had F2F delivery (p < .001) were more likely to spend more time on the intervention. Adjusting for baseline knowledge and modality, more time spent on the intervention was associated with higher posttest knowledge (p=.006).

Conclusions

Future studies are necessary to understand reasons underpinning engagement and to investigate other unmeasured factors, such as intervention interactivity elements, that could also be associated with engagement.

Innovation

This study of young adults with SCD or SCT provides much needed insight about their engagement with online reproductive health education.

Barriers to hydroxyurea use from the perspectives of providers, individuals with sickle cell disease, and families: Report from a U.S. regional collaborative

Sickle cell disease (SCD) is an inherited blood disorder that affects about 100,000 people in the U.S., primarily Blacks/African-Americans. A multitude of complications negatively impacts quality of life. Hydroxyurea has been FDA approved since 1998 as a disease-modifying therapy for SCD, but is underutilized. Negative and uninformed perceptions of hydroxyurea and barriers to its use hinder adherence and promotion of the medication. As the largest real-world study to date that assessed hydroxyurea use for children and adults with SCD, we gathered and analyzed perspectives of providers, individuals with SCD, and families. Participants provided information about socio-demographics, hospital and emergency admissions for pain, number of severe pain episodes interfering with daily activities, medication adherence, and barriers to hydroxyurea. Providers reported on indications for hydroxyurea, reasons not prescribed, and current laboratory values. We found that hydroxyurea use was reported in over half of eligible patients from this large geographic region in the U.S., representing a range of sickle cell specialty clinical settings and practices. Provider and patient/caregiver reports about hydroxyurea use were consistent with one another; adults 26 years and older were least likely to be on hydroxyurea; and the likelihood of being on hydroxyurea decreased with one or more barriers. Using the intentional and unintentional medication nonadherence framework, we found that, even for patients on hydroxyurea, challenges to taking the medicine at the right time and forgetting were crucial unintentional barriers to adherence. Intentional barriers such as worry about side effects and “tried and it did not work” were important barriers for young adults and adults. For providers, diagnoses other than HgbSS or HgbS-β0 thalassemia were associated with lower odds of prescribing, consistent with evidence-based guidelines. Our results support strengthening provider understanding and confidence in implementing existing SCD guidelines, and the importance of shared decision making. Our findings can assist providers in understanding choices and decisions of families; guide individualized clinical discussions regarding hydroxyurea therapy; and help with developing tailored interventions to address barriers. Addressing barriers to hydroxyurea use can inform strategies to minimize similar barriers in the use of emerging and combination therapies for SCD.

Acceptable, hopeful, and useful: development and mixed-method evaluation of an educational tool about reproductive options for people with sickle cell disease or trait

PURPOSE

People with sickle cell disease (SCD) or trait have many reproductive options, some of which decrease the chance of passing SCD to children, including in vitro fertilization with preimplantation genetic testing (IVF + PGT). Few are aware of these options, and educational materials are needed. This study aimed to develop an accessible, non-directive patient education material about reproductive options for those with SCD or trait via a process that incorporated stakeholders from the SCD community.

METHODS

Multidisciplinary stakeholders guided development and revision of a novel pamphlet. Researchers applied health literacy scales to measure pamphlet understandability. We interviewed nine patients with SCD and six multidisciplinary clinicians to evaluate the pamphlet. Interviews were recorded, transcribed, and coded by a five-member team who developed a codebook and proposed themes that were revised by all research team members. Feedback was incorporated into a revised pamphlet.

RESULTS

A two-page pamphlet describing reproductive options for people with SCD including IVF + PGT was acceptable to key stakeholders, including people with SCD. Material about this complex topic met health literacy standards, including being written at a 5th grade level. Patients reported feeling hopeful after reviewing the pamphlet, and participants considered the pamphlet useful, clear, and appropriate for distribution in clinics and online.

CONCLUSIONS

Though awareness of reproductive options for those with SCD or trait is low, patients and providers find a novel pamphlet about this topic acceptable and useful. Educational materials about complex topics including IVF + PGT can be written at a level understandable to the average American.

Toward a Conversational Agent to Support the Self-Management of Adults and Young Adults With Sickle Cell Disease: Usability and Usefulness Study

Sickle cell disease (SCD) is the most common genetic blood disorder in the world and affects millions of people. With aging, patients encounter an increasing number of comorbidities that can be acute, chronic, and potentially lethal (e.g., pain, multiple organ damages, lung disease). Comprehensive and preventive care for adults with SCD faces disparities (e.g., shortage of well-trained providers). Consequently, many patients do not receive adequate treatment, as outlined by evidence-based guidelines, and suffer from mistrust, stigmatization or neglect. Thus, adult patients often avoid necessary care, seek treatment only as a last resort, and rely on self-management to maintain control over the course of the disease. Hopefully, self-management positively impacts health outcomes. However, few patients possess the required skills (e.g., disease-specific knowledge, self-efficacy), and many lack motivation for effective self-care. Health coaching has emerged as a new approach to enhance patients' self-management and support health behavior changes. Recent studies have demonstrated that conversational agents (chatbots) could effectively support chronic patients' self-management needs, improve self-efficacy, encourage behavior changes, and reduce disease-severity. To date, the use of chatbots to support SCD self-management remains largely under-researched. Consequently, we developed a high-fidelity prototype of a fully automated health coaching chatbot, following patient-important requirements and preferences collected during our previous work. We recruited a small convenience sample of adults with SCD to examine the usability and perceived usefulness of the system. Participants completed a post-test survey using the System Usability Scale and the Usefulness Scale for Patient Information Material questionnaire. Thirty-three patients participated. The majority (64%) was affected by the most clinically severe SCD genotypes (Hb SS, HbSβ0). Most participants (94%) rated the chatbots as easy and fun to use, while 88% perceived it as useful support for patient empowerment. In the qualitative phase, 72% of participants expressed their enthusiasm using the chatbot, and 82% emphasized its ability to improve their knowledge about self-management. Findings suggest that chatbots could be used to promote the acquisition of recommended health behaviors and self-care practices related to the prevention of the main symptoms of SCD. Further work is needed to refine the system, and to assess clinical validity.

Effects of hydroxyurea on brain function in children with sickle cell anemia

INTRODUCTION

Sickle cell anemia (SCA) results in numerous adverse effects on the brain, including neurocognitive dysfunction. Hydroxyurea has been utilized extensively for management of SCA, but its effects on brain function have not been established.

METHODS

We examined prospectively the effects of 1 year of treatment with hydroxyurea on brain function in children with SCA (HbSS/HbSβ⁰ -thalassemia) by baseline and exit evaluations, including comprehensive neurocognitive testing, transcranial Doppler ultrasound (TCD), and brain MRI (silent cerebral infarcts [SCI], gray matter cerebral blood flow [GM-CBF], and blood oxygen level-dependent [BOLD] signal from visual stimulation).

RESULTS

Nineteen patients with SCA, mean age 12.4 years (range 7.2-17.8), were evaluated. At baseline, subjects had these mean values: full-scale IQ (FSIQ) 82.8, TCD velocity 133 cm/s, GM-CBF 64.4 ml/100 g/min, BOLD signal 2.34% increase, and frequency of SCI 47%. After 1 year of hydroxyurea, there were increases in FSIQ (+2, p = .059) and reading passage comprehension (+4, p = .033), a significant decrease in TCD velocity (-11 cm/s, p = .007), and no significant changes in GM-CBF, BOLD, or SCI frequency. Hemoglobin F (HbF) was associated with passage comprehension, hemoglobin with lower TCD velocity, and lower GM-CBF with greater working memory. Higher BOLD signal was associated with higher processing speed and lower TCD velocity with higher math fluency.

DISCUSSION

Improvements in neurocognition and decreased TCD velocity following 1 year of treatment support hydroxyurea use for improving neurocognitive outcomes in SCA. Understanding the mechanisms of benefit, as indicated by relationships of neurocognitive function with HbF, hemoglobin, and CBF, requires further evaluation.

Hydroxyurea treatment and neurocognitive functioning in sickle cell disease from school age to young adulthood

Neurocognitive impairment is common in sickle cell disease (SCD) and is associated with significant functional limitations. In a cross-sectional analysis, we examined the association between hydroxyurea (HU) treatment and neurocognitive functioning from school-age to young adulthood in individuals with SCD. A total of 215 patients with HbSS/HbSβ⁰ -thalassaemia (71% HU treated) and 149 patients with HbSC/HbSβ⁺ -thalassaemia (20% HU treated) completed neurocognitive measures at one of four developmental stages: school-age (age 8-9 years), early adolescence (age 12-13 years), late adolescence (age 16-17 years) and young adulthood (ages 19-24 years). For participants with multiple assessments, only the most recent evaluation was included. In multivariable analysis adjusted for social vulnerability, HU treatment and sex, older age was associated with a reduction in overall intelligence quotient (IQ) of 0·55 points per year of life [standard error (SE) = 0·18, false discovery rate adjusted P value (PFDR) = 0.01] for patients with HbSS/HbSβ⁰ -thalassaemia. Earlier initiation of HU (n = 152) in HbSS/HbSβ⁰ -thalassaemia was associated with higher scores on neurocognitive measures across most domains, including IQ [estimate (SE) 0·77 (0·25)/year, PFDR = 0·01], after adjusting for social vulnerability, sex and treatment duration. These results support the early use of HU to limit the detrimental neurocognitive effects of SCD, while highlighting the need for additional measures to further mitigate neurocognitive deterioration.

SC411 treatment can enhance survival in a mouse model of sickle cell disease

Sickle cell disease (SCD) is one of the most common inherited blood disorder among African Americans affecting 70,000-100,000 individuals in the United States. It is characterized by abnormal hemoglobin (HbS) which develops into severe hemolytic anemia and vaso-occlusive crisis. Therefore, patients with SCD suffer from a chronic state of inflammation, which is responsible for multiple organ damage, ischemic attacks, and premature death. Another major hallmark of SCD patients is the abnormally low levels of omega-3 fatty acids, especially docosahexaenoic acid (DHA) in their red blood cell membranes. Treatment with DHA can reduce red blood cell adhesion and enhance cerebral blood flow, thus, our main goal is to investigate the effect of SC411, which is a novel, highly purified DHA ethyl ester formulation with a proprietary delivery platform in SCD. Utilizing a transgenic mouse model of SCD (HbSS-Townes) and recurrent hypoxic challenges (10%O₂, 0.5% CO₂ and balance N₂ for 3 h) to mimic ischemic-like conditions, our data suggest that SC411 can elevate blood DHA and eicosapentaenoic acid (EPA) levels after 8 weeks of treatment. SC411 can also decrease arachidonic acid (AA) and sickling of red blood cells. In addition, SC411-treated SCD mice showed presented with cerebral blood flow, alleviated neuroinflammation, and revived working memory which ultimately enhanced overall survival. In summary, this study suggests that treatment with SC411 improves cellular and functional outcomes in SCD mice. This finding may provide novel therapeutic opportunities in the treatment against ischemic injury elicited by SCD.