Barriers to adherence of deferoxamine usage in sickle cell disease

Managing gastrointestinal challenges: Diarrhea in sickle cell anemia

Sickle cell anemia (SCA), a hereditary hemoglobinopathy, is characterized by the presence of abnormal hemoglobin and has long been associated with a wide range of complications. While much attention has been given to the condition hematological aspects, gastrointestinal complications, particularly diarrhea, have been relatively understudied and often overlooked. This publication delves into the management of gastrointestinal challenges, with a focus on diarrhea, in individuals living with SCA. The pathophysiology of SCA is intrinsically linked to gastrointestinal complications, and diarrhea is a common manifestation of this condition. This abstract publication outlines the key elements discussed in the full-length work, which includes the clinical presentation of diarrhea in these patients, the diagnostic tools used to evaluate the condition, and various management strategies to alleviate symptoms and enhance the overall quality of life for affected individuals. The paper emphasizes the importance of patient education, offering healthcare professionals valuable insights into how to inform and support patients in managing their conditions effectively. It also highlights the need for continued research to further our understanding of gastrointestinal challenges in SCA and to identify potential areas for future therapeutic interventions. Ultimately, the comprehensive management of diarrhea in individuals with SCA is vital for their overall well-being. This publication serves as a valuable resource for healthcare providers, researchers, and caregivers in addressing the gastrointestinal challenges that accompany SCA, ultimately working toward a better quality of life for those affected by this condition.

Deferiprone versus deferoxamine for transfusional iron overload in sickle cell disease and other anemias: Pediatric subgroup analysis of the randomized, open-label FIRST study

BACKGROUND

Children with sickle cell disease (SCD) who are chronically transfused often, require iron chelation therapy. There are limited data that allow for comparison of the efficacy and safety of the iron chelator deferiprone versus deferoxamine in children with SCD.

METHODS

This post hoc analysis of the phase 3b/4, randomized, open-label FIRST (Ferriprox in Patients with IRon Overload in Sickle Cell Disease Trial) study (NCT02041299) included patients 17 years and younger with SCD or other anemias receiving deferiprone or deferoxamine.

RESULTS

Overall, 142 patients were evaluated; mean ages were 10.5 and 11.7 years in the deferiprone and deferoxamine groups, respectively. At 12 months: mean change from baseline in liver iron concentration was -3.3 mg/g dry weight (dw) with deferiprone and -3.4 mg/g dw with deferoxamine (p = .8216); relative mean change (coefficient of variation %) in log cardiac T2* magnetic resonance imaging was 1.02 (21.8%) with deferiprone and 0.95 (19.5%) with deferoxamine (p = .0717); and the mean (standard error) change in serum ferritin levels was -133.0 (200.3) μg/L with deferiprone and -467.1 (244.1) μg/L with deferoxamine (p = .2924). The most common deferiprone-related adverse events (AEs) were upper abdominal pain (20.2%), vomiting (13.8%), pyrexia (9.6%), decreased neutrophil count (9.6%), increased alanine aminotransferase (ALT; 9.6%), and increased aspartate aminotransferase (AST; 9.6%). All cases of increased ALT, increased AST, and neutropenia resolved, most without intervention.

CONCLUSIONS

This post hoc analysis of pediatric patients from FIRST corroborated previous findings in adults that deferiprone is comparable to deferoxamine in reducing iron overload. No new safety concerns were observed. Deferiprone is an oral chelation option that could improve adherence and outcomes in children.

Self-Reported Medication Adherence Measured with Morisky Scales in Rare Disease Patients: A Systematic Review and Meta-Analysis

BACKGROUND

The visibility of Rare Diseases is a new challenge for society. These diseases are numerous, heterogeneous in nature and distribution, characterized by a high mortality rate but low prevalence, and usually presenting a severe evolution. Adherence to medication studies in rare diseases are uncommon, due to treatment scarcity.

OBJECTIVES

The main purpose of this study is to do a meta-analysis, evaluating the level of adherence to medication in the most prevalent rare diseases.

METHODS

This work is a systematic review, and meta-analysis was registered in the International Prospective Register of Systematic Reviews (PROSPERO) (Registration number: CRD42022372843) and conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Adherence to treatment in this systematic review and meta-analysis was collected from all studies included, based on the crude numerators and denominators reported, using either the Morisky Medication Adherence Scale 4 or -8.

RESULTS

A total of 54 records were identified through database searches, or after screening relevant manuscripts' references. Finally, 18 studies were included in this systematic review and meta-analysis. A total of 1559 participants (54.18% women) aged less than 84 years old were included. Twelve studies used the MMAS-8. In 8 of them, they established the level of adherence to treatment in three categories (low, medium, and high), with the mean prevalence in each of them being 41.4%, 30.4%, and 28.2%, respectively.

CONCLUSIONS

The results observed in adherence to treatment in patients with rare diseases show great variability, due to the different aspects involved in the greater or lesser applicability of the medication.

Management of Older Adults with Sickle Cell Disease: Considerations for Current and Emerging Therapies

People with sickle cell disease (SCD) are living longer than ever before, with the median survival increasing from age 14 years in 1973, beyond age 40 years in the 1990s, and as high as 61 years in recent cohorts from academic centers. Improvements in survival have been attributed to initiatives, such as newborn screening, penicillin prophylaxis, vaccination against encapsulated organisms, better detection and treatment of splenic sequestration, and improved transfusion support. There are an estimated 100,000 people living with SCD in the United States and millions of people with SCD globally. Given that the number of older adults with SCD will likely continue to increase as survival improves, better evidence on how to manage this population is needed. When managing older adults with SCD (defined herein as age ≥ 40 years), healthcare providers should consider the potential pitfalls of extrapolating evidence from existing studies on current and emerging therapies that have typically been conducted with participants at mean ages far below 40 years. Older adults with SCD have historically had little to no representation in clinical trials; therefore, more guidance is needed on how to use current and emerging therapies in this population. This article summarizes the available evidence for managing older adults with SCD and discusses potential challenges to using approved and emerging drugs in this population.

Managing the Cerebrovascular Complications of Sickle Cell Disease: Current Perspectives

The importance of protecting brain function for people with sickle cell disease (SCD) cannot be overstated. SCD is associated with multiple cerebrovascular complications that threaten neurocognitive function and life. Without screening and preventive management, 11% of children at 24% of adults with SCD have ischemic or hemorrhagic strokes. Stroke screening in children with SCD is well-established using transcranial Doppler ultrasound (TCD). TCD velocities above 200 cm/s significantly increase the risk of stroke, which can be prevented using chronic red blood cell (RBC) transfusion. RBC transfusion is also the cornerstone of acute stroke management and secondary stroke prevention. Chronic transfusion requires long-term management of complications like iron overload. Hydroxyurea can replace chronic transfusions for primary stroke prevention in a select group of patients or in populations where chronic transfusions are not feasible. Silent cerebral infarction (SCI) is even more common than stroke, affecting 39% of children and more than 50% of adults with SCD; management of SCI is individualized and includes careful neurocognitive evaluation. Hematopoietic stem cell transplant prevents cerebrovascular complications, despite the short- and long-term risks. Newer disease-modifying agents like voxelotor and crizanlizumab, as well as gene therapy, may treat cerebrovascular complications, but these approaches are investigational.

Evaluation of Glutamine Utilization in Patients With Sickle Cell Disease

Glutamine (Gln) was FDA-approved in 2017 to reduce acute sickle cell disease (SCD) pain and acute chest syndrome. However, typical pediatric patients with SCD exhibit moderate adherence, measured by a medication possession ratio <80%. This study examined Gln utilization in a "real-world" clinical setting to determine factors influencing medication adherence and to characterize the impact of an interdisciplinary team approach at an institution with specialty pharmacy services. A retrospective chart review identified 40 patients prescribed Gln by sickle cell specialists over a 2-year period and met selection criteria. Gln medication possession ratio for pediatric (72%) and adult (76%) patients were higher than other SCD medications. Pediatric patients (74%) demonstrated significantly lower first-attempt insurance approval rate compared with adult patients (95%) ( P =0.0026), suggesting an initial access barrier for pediatric patients. Pediatric patients demonstrated significantly higher number of medication fills (9.11 fills) compared with adult patients (3.86 fills) ( P =0.007), which suggests interdisciplinary collaboration may facilitate sustainable management of a new therapy. The majority of pediatric (89%) and adult (90%) patients reported high satisfaction with Gln ("excellent") with minor or no side effects. Multidisciplinary health care provider collaborations and tracking medication adherence metrics can help address barriers to care for SCD patients.

New Deferric Amine Compounds Efficiently Chelate Excess Iron to Treat Iron Overload Disorders and to Prevent Ferroptosis

Excess iron accumulation occurs in organs of patients with certain genetic disorders or after repeated transfusions. No physiological mechanism is available to excrete excess iron and iron overload to promote lipid peroxidation to induce ferroptosis, thus iron chelation becomes critical for preventing ion toxicity in these patients. To date, several iron chelators have been approved for iron chelation therapy, such as deferiprone and deferoxamine, but the current iron chelators suffer from significant limitations. In this context, new agents are continuously sought. Here, a library of new deferric amine compounds (DFAs) with adjustable skeleton and flexibility is synthesized by adopting the beneficial properties of conventional chelators. After careful evaluations, compound DFA1 is found to have greater efficacy in binding iron through two molecular oxygens in the phenolic hydroxyl group and the nitrogen atom in the amine with a 2:1 stoichiometry. This compound remarkably ameliorates iron overload in diverse murine models through both oral and intravenous administration, including hemochromatosis, high iron diet-induced, and iron dextran-stimulated iron accumulation. Strikingly, this compound is found to suppress iron-induced ferroptosis by modulating the intracellular signaling that drives lipid peroxidation. This study opens a new approach for the development of iron chelators to treat iron overload.

Deferiprone vs deferoxamine for transfusional iron overload in SCD and other anemias: a randomized, open-label noninferiority study

Many people with sickle cell disease (SCD) or other anemias require chronic blood transfusions, which often causes iron overload that requires chelation therapy. The iron chelator deferiprone is frequently used in individuals with thalassemia syndromes, but data in patients with SCD are limited. This open-label study assessed the efficacy and safety of deferiprone in patients with SCD or other anemias receiving chronic transfusion therapy. A total of 228 patients (mean age: 16.9 [range, 3-59] years; 46.9% female) were randomized to receive either oral deferiprone (n = 152) or subcutaneous deferoxamine (n = 76). The primary endpoint was change from baseline at 12 months in liver iron concentration (LIC), assessed by R2* magnetic resonance imaging (MRI). The least squares mean (standard error) change in LIC was -4.04 (0.48) mg/g dry weight for deferiprone vs -4.45 (0.57) mg/g dry weight for deferoxamine, with noninferiority of deferiprone to deferoxamine demonstrated by analysis of covariance (least squares mean difference 0.40 [0.56]; 96.01% confidence interval, -0.76 to 1.57). Noninferiority of deferiprone was also shown for both cardiac T2* MRI and serum ferritin. Rates of overall adverse events (AEs), treatment-related AEs, serious AEs, and AEs leading to withdrawal did not differ significantly between the groups. AEs related to deferiprone treatment included abdominal pain (17.1% of patients), vomiting (14.5%), pyrexia (9.2%), increased alanine transferase (9.2%) and aspartate transferase levels (9.2%), neutropenia (2.6%), and agranulocytosis (0.7%). The efficacy and safety profiles of deferiprone were acceptable and consistent with those seen in patients with transfusion-dependent thalassemia. This trial study was registered at www://clinicaltrials.gov as #NCT02041299.

HABIT efficacy and sustainability trial, a multi-center randomized controlled trial to improve hydroxyurea adherence in youth with sickle cell disease: a study protocol

Background

Hydroxyurea (HU) is recommended as standard practice for youth with sickle cell disease (SCD). Yet, despite its efficacy, HU adherence in adolescents and young adults is often poor. Poor medication adherence increases disease burden, healthcare cost and widens health disparities. Adolescence is a critical time to improve adherence through improved chronic disease self-management. This study aims to test the efficacy of an intervention delivered to youth/parent dyads by community health workers (CHWs), augmented by tailored text messages on HU adherence (primary outcome). Secondary outcomes are intervention sustainability, youth health-related quality of life, self-management responsibility concordance, acute hospital use and self-reported disease symptoms.

Methods

Hydroxyurea Adherence for Personal Best in Sickle Cell Disease, “HABIT,” is a 12 month multi-center randomized controlled trial. One hundred four youth, 10 to 18 years of age prescribed HU who meet eligibility criteria, enrolled with their parent as dyads, will be randomized 1:1 to either the HABIT intervention or to usual clinical care plus education handouts. All subjects will complete clinic visits at months 0, 2, 4, 6 (efficacy component), 9 and 12 (sustainability component) for assessment of HbF biomarker, other hematologic parameters, and to complete questionnaires. In addition, dyads assigned to the HABIT intervention will work with CHWs to identify a daily habit (e.g., brushing teeth) on which to build a HU adherence habit. Tailored daily text message reminders to support the habit will be developed by the dyad in collaboration with the CHWs and sent to parent and youth. At the 6 month visit, the intervention will end and the sustainability portion of the trial will begin. All data analyses will be based on intention to treat with all randomized subjects included in the analyses.

Discussion

Prior retrospective studies demonstrate that a majority of adolescents are poorly adherent to HU. If efficacious, the HABIT intervention has the potential to improve the lives of youth with SCD.

Trial registration

Clinicaltrials.gov NCT03462511. Registered March 6, 2018, last updated July 26, 2019.

Family Functioning, Medical Self-Management, and Health Outcomes Among School-Aged Children With Sickle Cell Disease: A Mediation Model

Background

Informed by the Pediatric Self-Management Model, the present study tested relationships between parent and family functioning, sickle cell disease (SCD) self-management, and health outcomes for children with SCD.

Method

83 children with SCD and a parent completed baseline data as part of a larger investigation of a family-based, problem-solving intervention for children with SCD (M age = 8.47). Youth and parents completed a measure of child health-related quality of life (HRQOL), and parents completed measures of family efficacy, parenting stress, and SCD self-management. SCD pain episodes and urgent health utilization information over the past year were obtained via medical chart review.

Results

SCD self-management mediated the relationship between parent-reported family efficacy and parent proxy HRQOL, as well as the relationship between parenting stress and child and parent proxy HRQOL. Mediation models were nonsignificant for outcomes beyond HRQOL, including SCD pain episodes and urgent health utilization.

Conclusion

Fostering family efficacy and reducing parenting stress may be meaningful intervention targets for improving SCD self-management and child HRQOL among school-aged children. Although findings were consistent with the Pediatric Self-Management Model in terms of HRQOL, the model was not supported for pain episodes or urgent health utilization, highlighting the need for multi-method, longitudinal research on the SCD self-management behaviors that are linked to preventable health outcomes.

Psychological Factors Associated with Episodic Chelation Adherence in Thalassemia

β-Thalassemia major (β-TM) is a life-long genetic hemoglobin (Hb) disorder requiring intensive treatment regimens, including frequent blood transfusions and daily chelation therapy. Understanding psychosocial correlates of chelation adherence is important for developing interventions to improve adherence. This study investigated within-participant correlates of oral chelation adherence on a daily (episodic) basis. Thirty-seven adult participants with β-TM were recruited from clinics at two hospitals (22 males, 9 females, mean age 34.5 years, range 19-54 years). A structured interview was used to assess behavioral and psychological situational variables related to an adherent and a nonadherent episode for each participant. Positive outcome expectancies and higher self-efficacy were both significantly associated with adherent episodes. Behavioral variables, including difficulty in accessing medication, location, and whether alone or with others, were also associated with nonadherent episodes. Findings suggested that situational psychological factors are important for chelation adherence. Adherence interventions should consider focusing on potentially modifiable situational variables (psychological and behavioral).

Utilizing a Novel Mobile Health "Selfie" Application to Improve Compliance to Iron Chelation in Pediatric Patients Receiving Chronic Transfusions

Iron chelation therapy can prevent iron overload for pediatric patients with sickle cell disease and β-thalassemia major; however, adherence is suboptimal. Therefore, we developed an intensive training program (ITP), to improve medication management and disease knowledge. The objectives were to determine feasibility of the ITP and its preliminary impact on adherence, disease knowledge, and health outcomes. Pediatric patients were recruited to participate in the ITP over a 90-day period and were followed for 6 months. The ITP consisted of 3 components: (1) provider-led education modules; (2) patient recording daily videos of at-home medication administration; and (3) provider feedback through video messages through the ITP app. Eleven patients participated (mean=12.4 y). Initially, patients endorsed high satisfaction and ease of use and tracked their medication usage 81% (24 out of 30) of days. At 90 days, adherence rates remained consistent (80%) and disease knowledge retention was high (96%). At 6 months, participants exhibited a clinically relevant decrease in serum ferritin, which trended toward statistical significance (P=0.068). Medication possession ratio did not significantly increase (0.65 to 0.72; not significant). The mobile ITP was feasibly implemented in a clinical setting; in addition, high levels of compliance, disease knowledge retention, and acceptance encourage larger studies evaluating mobile health technology to improve child health parameters.

Study protocol for a randomized controlled trial to assess the feasibility of an open label intervention to improve hydroxyurea adherence in youth with sickle cell disease

BACKGROUND

Community health workers (CHW) are increasingly recognized as a strategy to improve health outcomes for the underserved with chronic diseases but has not been formally explored in adolescents with sickle cell disease (SCD). SCD primarily affects African American, Hispanic and other traditionally underserved populations. Hydroxyurea (HU), an oral, once-daily medication, is the only approved therapeutic drug for sickle cell disease and markedly reduces symptoms, morbidity and mortality and improves quality of life largely by increasing hemoglobin F blood levels. This paper presents the rationale, study design and protocol for an open label randomized controlled trial to improve parent-youth partnerships in self-management and medication adherence to HU in adolescents with SCD.

METHODS/DESIGN

A CHW intervention augmented by text messaging was designed for adolescents with SCD ages 10-18years and their parents to improve daily HU adherence. Thirty adolescent parent dyads will be randomized with 2:1 intervention group allocation. Intervention dyads will establish a relationship with a culturally aligned CHW to identify barriers to HU use, identify cues to build a habit, and develop a dyad partnership to improve daily HU adherence and achieve their individualized "personal best" hemoglobin F target. Intervention feasibility, acceptability and efficacy will be assessed via a 2-site trial. Outcomes of interest are HU adherence, dyad self-management communication, quality of life, and resource use.

DISCUSSION

Despite known benefits, poor HU adherence is common. If feasible and acceptable, the proposed intervention may improve health of underserved adolescents with SCD by enhancing long-term HU adherence.

TRIAL REGISTRATION

NCT02029742.

Evidence for multidimensional resilience in adult patients with transfusion-dependent thalassemias: Is it more common than we think?

BACKGROUND

Life expectancy of patients with transfusion-dependent thalassemias has increased with the development of improved treatment over the last few decades. However, β-thalassemia disorder still has considerable lifetime treatment demands and heightened risk of frequent complications due to transfusion-transmitted infections and iron overload, which may affect thalassemic patients' functioning in different domains.

OBJECTIVES

The vast majority of published studies on thalassemic patients have focused on children and adolescent functioning, and little research has examined adults. Hence, the current study was planned to examine the functioning and resilience of adult thalassemic patients in a comprehensive way.

METHODS

We examined multidimensional resilience and functioning across different domains (psychological adjustment, treatment adherence, social functioning and occupational functioning). We also examined demographic and medical variables that may relate to resilience and functioning. Participants were adult patients [n = 38; age M = 31·63, standard deviation (SD) = 7·72; 72% female] with transfusion-dependent thalassemia in treatment in a hospital in the northeastern United States.

RESULTS

The results suggest that most adult thalassemic patients tend to be resilient, demonstrating good functioning in four main domains: psychological adjustment, treatment adherence, social functioning and occupational functioning.

CONCLUSION

Despite the considerable demands of their illness, adult thalassemic patients appeared to be adapting well, demonstrating evidence of multidimensional resilience.

Systematic and Meta-Analytic Review: Medication Adherence Among Pediatric Patients With Sickle Cell Disease

OBJECTIVE

To provide a comprehensive summary (systematic review) of medication adherence rates by assessment method and medication type for pediatric patients with sickle cell disease (SCD), as well as identify important correlates for future research.

METHODS

Articles assessing medication adherence and published between 1982 and February 2015 (n = 49) were identified using electronic databases. A meta-analysis of 14 studies examining demographic, medical, and psychosocial factors and medication adherence was conducted.

RESULTS

Adherence rates ranged from 12% to 100% across all medications. Approximately 30% of studies reported associations between adherence and key demographic, medical, and psychosocial correlates. Mean effect sizes were small to moderate (r = .02-.53).

CONCLUSIONS

The wide range of adherence rates reported in the literature may be because of, in part, the use of variable assessment strategies. Future studies examining pediatric SCD adherence should incorporate key correlates with the goal of replication.

Medication adherence among pediatric patients with sickle cell disease: a systematic review

OBJECTIVES

Describe rates of adherence for sickle cell disease (SCD) medications, identify patient and medication characteristics associated with nonadherence, and determine the effect of nonadherence and moderate adherence (defined as taking 60%-80% of doses) on clinical outcomes.

METHODS

In February 2012 we systematically searched 6 databases for peer-reviewed articles published after 1940. We identified articles evaluating medication adherence among patients <25 years old with SCD. Two authors reviewed each article to determine whether it should be included. Two authors extracted data, including medication studied, adherence measures used, rates of adherence, and barriers to adherence.

RESULTS

Of 24 articles in the final review, 23 focused on 1 medication type: antibiotic prophylaxis (13 articles), iron chelation (5 articles), or hydroxyurea (5 articles). Adherence rates ranged from 16% to 89%; most reported moderate adherence. Medication factors contributed to adherence. For example, prophylactic antibiotic adherence was better with intramuscular than oral administration. Barriers included fear of side effects, incorrect dosing, and forgetting. Nonadherence was associated with more vaso-occlusive crises and hospitalizations. The limited data available on moderate adherence to iron chelation and hydroxyurea indicates some clinical benefit.

CONCLUSIONS

Moderate adherence is typical among pediatric patients with SCD. Multicomponent interventions are needed to optimally deliver life-changing medications to these children and should include routine monitoring of adherence, support to prevent mistakes, and education to improve understanding of medication risks and benefits.

Adherence-related issues in adolescents and young adults with hematological disorders

Nonadherence to medical recommendations is a widespread problem well documented in a multitude of clinical settings. Nonadherence may adversely affect clinical outcomes such as survival and quality of life and increase health-care-related costs. An understanding of the factors driving nonadherence is key to developing effective adherence-enhancing interventions (AEIs). There are ongoing attempts in contemporary adherence research to better define the various components of adherence, to find optimal measures of adherence and correlations with clinical outcomes, and to create a classification system for AEIs. Nonadherence is also widely prevalent among adolescents and young adults (AYAs) with chronic hematological diseases, affecting up to 50% of patients and increasing with age. Combined use of objective (i.e. electronic monitoring, EM) and subjective (i.e. self-report) measures of adherence may be the preferred approach to assess adherence. The unique physical, social and emotional aspects of the AYA life stage are closely related to intricate causes of nonadherence in AYAs such as problems in transition to adult care. Until proven otherwise, the empirical target in AYAs with hematological disorders should be perfect adherence. Multilevel AEIs, EM feedback and behavioral interventions are among the most effective types of AEIs. Despite the magnitude of the problem, only a handful of AEIs have been evaluated among AYAs with hematological disorders. Thus, this is a field with unmet needs warranting high-quality trials using standardized and well-specified assessment methods and interventions. This review discusses the prevalence, definition, causes and clinical implications of nonadherence among AYAs with hematological disorders, along with strategies to measure and improve adherence.

Integrating interactive web-based technology to assess adherence and clinical outcomes in pediatric sickle cell disease

Research indicates that the quality of the adherence assessment is one of the best predictors for improving clinical outcomes. Newer technologies represent an opportunity for developing high quality standardized assessments to assess clinical outcomes such as patient experience of care but have not been tested systematically in pediatric sickle cell disease (SCD). The goal of the current study was to pilot an interactive web-based tool, the Take-Charge Program, to assess adherence to clinic visits and hydroxyurea (HU), barriers to adherence, solutions to overcome these barriers, and clinical outcomes in 43 patients with SCD age 6–21 years. Results indicate that the web-based tool was successfully integrated into the clinical setting while maintaining high patient satisfaction (>90%). The tool provided data consistent with the medical record, staff report, and/or clinical lab data. Participants reported that forgetting and transportation were major barriers for adherence to both clinic attendance and HU. A greater number of self-reported barriers (P < .01) and older age (P < .05) were associated with poorer clinic attendance and HU adherence. In summary, the tool represents an innovative approach to integrate newer technology to assess adherence and clinical outcomes for pediatric patients with SCD.

Stroke With Transfusions Changing to Hydroxyurea (SWiTCH): a phase III randomized clinical trial for treatment of children with sickle cell anemia, stroke, and iron overload

BACKGROUND

Stroke occurs in 5-10% of children with sickle cell anemia (SCA) and has a high (>50%) risk of recurrence without therapy. Chronic monthly erythrocyte transfusions effectively prevent recurrent stroke, but their long-term use is limited by serious side effects, including iron overload. An alternative to transfusion for secondary stroke prevention in SCA is needed, especially one that also improves the management of iron overload.

METHODS

Stroke With Transfusions Changing to Hydroxyurea (SWiTCH) is an NHLBI-sponsored Phase III multicenter randomized controlled clinical trial for children with SCA, stroke, and iron overload (NCT00122980). The primary goal of SWiTCH is to compare 30 months of alternative therapy (hydroxyurea and phlebotomy) with standard therapy (transfusions and chelation) for the prevention of secondary stroke and reduction of transfusional iron overload.

DISCUSSION

SWiTCH has several distinctive study features including novel methodological and design components: (1) composite primary endpoint including both stroke recurrence rate and iron burden; (2) non-inferiority design with an "acceptable" increased stroke risk; (3) transfusion goals based on current academic community practices; (4) special oversight for the enrollment and randomization process; (5) overlap treatment period within the alternative treatment arm; (6) masking of the overall trial Principal Investigator to treatment results; (7) inclusive independent stroke adjudication process for all suspected new neurological events; and (8) periodic therapeutic phlebotomy program to alleviate iron overload.

CONCLUSION

Investigation of alternative treatments in SWiTCH could lead to changes in the management of cerebrovascular disease for selected patients with SCA, stroke, and iron overload.

Disease management, coping, and functional disability in pediatric sickle cell disease

BACKGROUND

Youth with sickle cell disease (SCD) experience chronic symptoms that significantly interfere with physical, academic, and social-emotional functioning. Thus, to effectively manage SCD, youth and caregivers must work collaboratively to ensure optimal functioning. The goal of the current study was to examine the level of involvement in disease management tasks for youth with SCD and their caregivers. The study also examined the relationship between involvement in disease management tasks, daily functioning, and coping skills. The study utilized collaborative care and disease management theoretical frameworks.

METHODS

Youth and caregivers participated in the study during an annual research and education day event. Forty-seven patients with SCD aged 6 to 18 years and their caregivers completed questionnaires examining level of involvement in disease management tasks, youth functional disability, and youth coping strategies. Caregivers also completed a demographic and medical history form.

RESULTS

Parents and youth agreed that parents were significantly more involved in disease management tasks than youth, although level of involvement varied by task. Decreased parent involvement was related to greater coping strategies used by patients, including massage, prayer, and positive thinking. Higher functional disability (lower functioning) was related to greater parent involvement in disease management tasks, suggesting that greater impairment may encourage increased parent involvement.

CONCLUSIONS

Health professionals working with families of youth with SCD should discuss with parents and youth how disease management tasks and roles will be shared and transferred during adolescence. Parents and youth may also benefit from a discussion of these issues within their own families.

Which psychosocial factors are related to chelation adherence in thalassemia? A systematic review

Good adherence to iron chelation therapy in thalassemia is crucial. Although there is evidence that adherence is related to regimen factors, there has been less emphasis on the relationship between psychosocial (psychological, demographic and social) factors and adherence. We present a systematic review of psychosocial correlates of chelation adherence in thalassemia. Nine studies met the inclusion criteria. Information was extracted regarding the study characteristics and the relationship between psychosocial factors and chelation adherence. Methodological quality was rated. The studies took place in a range of countries, were mostly cross sectional in design, and examined adherence to deferoxamine (DFO) only. Sample sizes ranged from 15 to 1573. A variety of psychosocial variables were examined. Definitions of adherence varied between studies and non adherence rates were also variable (9 to 66%). Older age was consistently associated with lower levels of chelation adherence. There were few other consistent findings. The methodological quality of studies was variable. There is a need for more methodologically sophisticated and theoretically informed studies on psychosocial correlates of chelation adherence. We offer specific suggestions.

Iron in sickle-cell disease: what have we learned over the years?

Over the last four decades, monumental advances have been made in the understanding, assessment, and management of transfusion-dependent patients, which have translated into significant improvements in patient morbidity and mortality. Important lessons have been learned from extensive clinical experience of iron management in the thalassemias, but greater knowledge of key differences in the sickle-cell disease (SCD) population may impact on our approach to patient assessment and management. The unique pathophysiology of SCD is reflected in a distinct pattern of iron loading with minimal organ-specific injury. An appreciation and understanding of these differences should allow us to develop tailored management approaches that optimize patient outcomes.

Adherence to hydroxyurea therapy in children with sickle cell anemia

OBJECTIVES

To assess adherence to hydroxyurea therapy in children with sickle cell anemia (SCA), evaluate the association between adherence and hematologic profile, and identify barriers and facilitators of adherence.

STUDY DESIGN

Children with SCA (n=75) receiving hydroxyurea were recruited for a single-institution cross-sectional study. The primary outcome was association between treatment adherence and percent fetal hemoglobin (HbF).

RESULTS

Good adherence was estimated at 82% with visual analog scale, 84% with Morisky score, 85% with medical provider report, 77% with clinic visits, and 49% on the basis of pharmacy refills. Increase in HbF was moderately associated with good adherence as measured with the parent/proxy Morisky score (r=-0.39; 95% CI, -0.58-0.17; P < .01) and prescription refills (r=0.39; 95% CI, 0.16-0.57; P < .01). The number of pharmacy refills and the Morisky score explained 23% of the variation in HbF response.

CONCLUSIONS

Adherence was > or =75% with 4 of 5 measures. Pharmacy refills and the Modified Morisky Scale may be used to identify children at high risk for poor response because of non-adherence and children with good adherence with poor response because of individual pharmacodynamics. Future research should prospectively compare adherence measures and evaluate methods to improve treatment adherence.

Adherence to study medication and visits: data from the BABY HUG trial

BACKGROUND

Subject retention and adherence are essential to maintain the power and validity of the Pediatric Hydroxyurea Phase III Clinical Trial (BABY HUG). We designed a study to assess adherence with study medication administration and study visits and to evaluate socioeconomic factors (SES) that may influence these measurements of adherence. These data are important for assessing impact of adherence on BABY HUG trial outcome and defining impact of SES on adherence.

METHODS

Each subject's median study medication (MedAd) and mean visit adherence (VAd) were evaluated. We examined associations of adherence with SES of participating families.

RESULTS

MedAd data were available on 153 of the 191 subjects who started randomized study medication. MedAd was 101.7% of volume prescribed, with 88.9% of subjects taking at least 80% of doses. VAd data were available on 185 of the 191 subjects who started randomized study medication. VAd was 97.3%, with 82.2% of subjects having no missed visits. During dose titration, subjects had on average 12.9% higher medication adherence than subjects who were on a stable dose and had less frequent study visits. MedAd and VAd were not significantly associated with SES.

CONCLUSION

Subjects in the BABY HUG trial have had excellent adherence. SES was not associated with adherence, suggesting that SES should not be used as a criterion for enrolment in clinical trials. Additional efforts are needed to maintain medication adherence, particularly when the interval between scheduled visits increases. (ClinicalTrials.gov number, NCT00006400).

Adherence to deferasirox in children and adolescents with sickle cell disease during 1-year of therapy

BACKGROUND

Adherence to long-term treatment is challenging. Deferasirox (DFX) is a daily oral iron chelator approved in the United States for transfusional iron overload.

PROCEDURES

Twenty-one subjects with sickle cell disease (mean age 13.8+/-4.2 y) received DFX 20 to 30 mg/kg daily for 1-year while on chronic blood transfusions. Good adherence to DFX was defined as > or =80% intake of prescribed dose. Adherence was assessed by monthly pill counts and calendars, and questionnaires at 1, 3, 6, and 12 months follow-up.

RESULTS

Fifteen of 21 subjects (71%) were adherent to DFX according to self-reports, with 83% of the patients being adherent at 1 month, 89% at 3 months, 65% at 6 months, and 78% at 12 months. We were only able to document continuous good adherence in 43% of patients by pill counts because of poor bottle return. The discrepancy between pill counts and self-reports may be related to over-reporting, with the real adherence being lower. Parental involvement with DFX administration (P=0.03) and age < or =16 years (P=0.0055) correlated with adherence. We could not detect a significant correlation between serum ferritin declines and adherence.

CONCLUSION

Seventy-one percent of patients adhered to DFX according to questionnaire responses but only 43% did according to pill counts. Adherence was poorer in adolescents older than 16 years of age and in patients who had no parental supervision of medications.

Oral iron chelation and the treatment of iron overload in a pediatric hematology center

BACKGROUND

Recent advances have led to the development of oral iron chelators, which have changed clinical practice. The objective of this study was to descriptively assess the use of one such agent, deferasirox, as standard of care treatment in a large pediatric hematology center.

PROCEDURE

We retrospectively studied all patients at the Texas Children's Hematology Center who were previously or currently treated with deferasirox. We gathered data on demographics, clinical diagnoses, length of time on chronic transfusions, previous use of deferoxamine, adherence to therapy, and reasons for discontinuation. We also assessed changes in serum ferritin, liver function tests, and creatinine for those on deferasirox for a minimum of 12 months.

RESULTS

Fifty-nine patients were studied. Eighty-one percent of patients treated with deferasirox had a diagnosis of sickle cell disease. The mean baseline ferritin level for our study population was 2,117 ng/ml (range 754-7,211). Fifty-three percent of patients had been previously treated with deferoxamine. Adherence to oral therapy was documented in 76% of patients. For those on deferasirox for a minimum of 12 months, serum ferritin decreased in 30% of patients (44% of compliant patients, 11% of poorly compliant patients). Changes in creatinine and liver function tests were mild and did not result in long-term discontinuation of deferasirox in any cases.

CONCLUSIONS

Outside of controlled clinical trials, deferasirox can be utilized safely as an oral iron chelator in children although adherence to therapy and the complex interaction of factors that contribute to iron overload still present challenges for clinicians.

Satisfaction and adherence in patients with iron overload receiving iron chelation therapy as assessed by a newly developed patient instrument

OBJECTIVES

This study assesses satisfaction with iron chelation therapy (ICT) based on a reliable and valid instrument, and explores the relationship between satisfaction and adherence to ICT.

METHODS

Patients in the USA and UK completed a new "Satisfaction with ICT" (SICT) instrument consisting of 28 items, three pertaining to adherence. Simple and multivariate regression analyses assessed the relationship between satisfaction with different aspects of ICT and adherence.

RESULTS

First assessments of the SICT instrument indicate its validity and reliability. Recommended thresholds for internal consistency, convergent validity, discriminant validity, and floor and ceiling effects were met. A number of variables were identified in the simple linear regression analyses as significant predictors of "never thinking about stopping ICT," a proxy for adherence. These significant variables were entered into the multivariate model to assess the combined factor effects, explaining 42% of the total variance of "never thinking about stopping ICT." A significant and positive relationship was demonstrated between "never thinking about stopping ICT" and age (P = 0.04), Perceived Effectiveness of ICT (P = 0.003), low Burden of ICT (P = 0.002), and low Side Effects of ICT (P = 0.01).

CONCLUSIONS

The SICT is a reliable and valid instrument which will be useful in ICT clinical trials. Furthermore, the administration of ICT by slow subcutaneous infusion negatively impacts on satisfaction with ICT which was shown to be a determinant of adherence. This points to the need for new more convenient and less burdensome oral iron chelators to increase adherence, and ultimately to improve patient outcomes.

Disparity in the management of iron overload between patients with sickle cell disease and thalassemia who received transfusions

BACKGROUND

Transfusion therapy is frequently used to prevent morbidity in sickle cell disease (SCD), and subsequent iron overload is common. The objective of this study was to evaluate the current standard of care in monitoring iron overload and related complications in patients with SCD compared to thalassemia (Thal).

STUDY DESIGN AND METHODS

A cross-sectional study was conducted at 31 hematology clinics in the United States, Canada, or the United Kingdom. Patients who received transfusions with a mean serum ferritin level of least 2000 ng per mL were eligible. A total of 199 patients with SCD (113 female; 24.9 +/- 13.2 years) and 142 with Thal (66 female; 25.8 +/- 8.1 years) were recruited, and data were collected between 2001 and 2003 by interview and medical record review.

RESULTS

Although both groups were recruited on the basis of significant iron overload, the likelihood of performing a liver biopsy for routine iron monitoring was significantly higher (odds ratio [OR], 3.4; 95% confidence interval [CI], 2.2-5.3) in Thal than SCD. Thal patients were also more likely to be screened for iron-related organ injury including an echocardiograph for cardiomyopathy (OR, 2.6; p < 0.001; 95% CI, 1.6-4.2), alanine aminotransferase for liver function (OR, 8.3; CI, 1.05-64.4), and thyroid-stimulating hormone for hypothyroidism (OR, 12.3; CI, 7.0-21.5). For adult SCD patients, those maintained on simple transfusion with a serum ferritin level of greater than 2500 ng per mL were the least likely to have a liver biopsy (p < 0.03).

CONCLUSIONS

These data highlight the unsystematic monitoring of iron and related organ injury in SCD. Until the relationship between iron and related comorbidities is better understood, routine monitoring of iron overload in SCD patients who receive transfusions should be considered a standard part of clinical care.

Neuropsychological assessment, neuroimaging, and neuropsychiatric evaluation in pediatric and adult patients with sickle cell disease (SCD)

Traditionally, neuropsychological deficits due to Sickle Cell Disease (SCD) have been understudied in adults. We have begun to suspect, however, that symptomatic and asymptomatic Cerebrovascular Events (CVE) may account for an alarming number of deficits in this population. In the current brief review, we critically evaluated the pediatric and adult literatures on the neurocognitive effects of SCD. We highlighted the studies that have been published on this topic and posit that early detection of CVE via neurocognitive testing, neuropsychiatric evaluations, and neuroimaging may significantly reduce adult cognitive and functional morbidities.

Light and shadows in the iron chelation treatment of haematological diseases

This review outlines the main chelator groups studied to date, and the evidence for their clinical effectiveness. For each treatment, the strength of evidence was documented according to the guidelines from the American College of Cardiology and the American Heart Association. Three main haematological diseases were considered as models: thalassaemia major, sickle-cell disorders and myelodysplasia. Although the data in the literature do not allow firmly evidence-based conclusions, the findings suggest that in thalassaemia major: (i) deferoxamine remains the drug of choice for chelation treatment; (ii) if there is deferoxamine intolerance or a change of treatment is suggested, the options are deferiprone or, if the liver iron concentration is high, deferasirox treatment; and (iii) if the ferritin level is >2500 microg/l and liver iron concentation is >7 mg/g/dry weight, continuous subcutaneous (s.c.) or intravenous (i.v.) deferoxamine, or combined treatment with deferiprone and deferoxamine is advised. In case of heart failure, there is currently more solid documentation to support continuous s.c. or i.v. deferoxamine treatment than combined treatment with deferiprone and deferoxamine. However, more recent data in the literature suggest that the latter could be a satisfactory alternative. Finally, if iron chelation is required for sickle-cell disorders or myelodysplastic syndromes, the current data support the use of deferoxamine treatment.

Optimal management strategies for chronic iron overload

Iron overload is characterised by excessive iron deposition and consequent injury and dysfunction of target organs, especially the heart, liver, anterior pituitary, pancreas and joints. Iron overload disorders are common worldwide and occur in most major race/ethnicity groups. Physiological mechanisms to excrete iron are very limited. Thus, all patients with iron overload need safe and effective treatment that is compatible with their co-existing medical conditions. Treatments for iron overload include phlebotomy and erythrocytapheresis that remove iron predominantly as haemoglobin, and chelation therapy with drugs that bind excess iron selectively and increase its excretion. The most important potential benefits of therapy are preventing deaths due to cardiac siderosis and hepatic cirrhosis. Preventing iron-related injury to endocrine organs is critical in children. Successful treatment or prevention of iron overload increases quality of life and survival in many patients. This article characterises the major categories of iron overload disorders, tabulates methods to evaluate and treat iron overload, and describes treatment options for iron overload disorders. Research needed to advance knowledge about treatment of iron overload is proposed.

Chelation therapy for iron overload

Iron overload is characterized by excessive iron deposition and consequent injury and dysfunction of the heart, liver, anterior pituitary, pancreas, and joints. Because physiologic mechanisms to excrete iron are very limited, patients with iron overload and its complications need safe, effective therapy that is compatible with their coexisting medical conditions. The availability of three licensed iron chelation drugs (one parenteral, two oral) and the development and clinical investigation of other oral chelators represent new opportunities to prevent or manage iron overload in patients with heritable types of severe anemia, such as beta-thalassemia major and sickle cell disease, and for the formulation of alternatives to phlebotomy therapy for patients with iron overload associated with the HFE gene and other adult age-of-onset types of hemochromatosis, African iron overload, and African-American iron overload.

Perceived adherence to prescribed treatment in juvenile idiopathic arthritis over a one-year period

OBJECTIVE

To document perceived adherence to treatment (taking medications and performing exercises) in patients with juvenile idiopathic arthritis (JIA) over a 1-year period and to identify related factors.

METHODS

We surveyed parents of patients with JIA at the Montreal Children's Hospital and British Columbia's Children's Hospital in Vancouver. Parents were asked to respond to a series of questionnaires every 3 months over a 12-month period. Perceived adherence was evaluated on a 100-mm visual analog scale (VAS) in the Parent Adherence Report Questionnaire (PARQ). Parental coping, distress, child function, disease severity and duration, perceived helpfulness of treatment, problems encountered, and sociodemographic data were also assessed.

RESULTS

The mean age of our sample of 175 children was 10.2 years; mean age at diagnosis was 6.1 years and mean disease duration was 4.1 years. Perceived adherence to medications was consistently high, with average adherence at baseline, 3, 6, 9, and 12 months being 86.1, 91.7, 90.4, 92.0, and 88.8, respectively, on the PARQ VAS. Perceived adherence to exercise was lower but remained steady, with corresponding means of 54.5, 64.1, 61.2, 63.0, and 54.3, respectively. Using generalized estimating equation analysis, factors associated with higher perceived adherence to medications included perceived helpfulness of medications and lower disease severity; those associated with higher perceived adherence to exercise were younger age of the child, child involvement in responsibility for treatment, and higher perceived helpfulness of the treatment.

CONCLUSION

Belief in helpfulness of treatment is associated with higher parental perceived adherence to treatment.

A randomised comparison of deferasirox versus deferoxamine for the treatment of transfusional iron overload in sickle cell disease

Deferasirox is a once-daily, oral iron chelator developed for treating transfusional iron overload. Preclinical studies indicated that the kidney was a potential target organ of toxicity. As patients with sickle cell disease often have abnormal baseline renal function, the primary objective of this randomised, open-label, phase II trial was to evaluate the safety and tolerability of deferasirox in comparison with deferoxamine in this population. Assessment of efficacy, as measured by change in liver iron concentration (LIC) using biosusceptometry, was a secondary objective. A total of 195 adult and paediatric patients received deferasirox (n = 132) or deferoxamine (n = 63). Adverse events most commonly associated with deferasirox were mild, including transient nausea, vomiting, diarrhoea, abdominal pain and skin rash. Abnormal laboratory studies with deferasirox were occasionally associated with mild non-progressive increases in serum creatinine and reversible elevations in liver function tests. Discontinuation rates from deferasirox (11.4%) and deferoxamine (11.1%) were similar. Over 1 year, similar dose-dependent LIC reductions were observed with deferasirox and deferoxamine. Once-daily oral deferasirox has acceptable tolerability and appears to have similar efficacy to deferoxamine in reducing iron burden in transfused patients with sickle cell disease.

A simple model to assess and improve adherence to iron chelation therapy with deferoxamine in patients with thalassemia

Adherence to deferoxamine (DFO) is vital for the long-term survival of patients with thalassemia; however, currently no measure exists to quantify adherence directly. In this study, 90 patients with thalassemia major underwent liver iron concentration (LIC) assessment by SQUID biosusceptometer, were asked to rate their adherence to DFO using a Numerical Likert Scale (NLS), and were educated about complications of iron overload. Of 38% (n = 28) of patients who rated themselves as very compliant, 19 had elevated LIC related to inadequate dosing of DFO and nine reported nonadherence in the past. Adherence improved after counseling and LIC decreased by 25% (7-60%) in eight previously noncompliant patients who returned for subsequent LIC over 15 months. In conclusion, the NLS seems to be a simple but reliable tool to assess patients' adherence to DFO. Education and frequent noninvasive LIC assessments can improve adherence and iron burden. Elevated LIC does not necessarily reflect concurrent noncompliance; however, it can be an indication of nonadherence in the past.

Red cell exchange in sickle cell disease

Red cell exchange transfusions remain an effective but possibly underutilized therapy in the acute and chronic treatment of sickle cell disease. In sickle cell disease, increased blood viscosity can cause complications when the hemoglobin exceeds 10 g/dL even if this is due to simple transfusion. Red cell exchange can provide needed oxygen carrying capacity while reducing the overall viscosity of blood. Acute red cell exchange is useful in acute infarctive stroke, in acute chest and the multi-organ failure syndromes, the right upper quadrant syndrome, and possibly priapism. Neither simple or exchange transfusions are likely to hasten resolution of an acute pain episode.