Examining the characteristics and beliefs of hydroxyurea users and nonusers among adults with sickle cell disease

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.

Understanding multi-level barriers to medication adherence among adults living with sickle cell disease

There is limited research that identifies and examines multi-level barriers to medication adherence among adults with Sickle Cell Disease (SCD); Identify multi-level barriers to medication adherence among adults with SCD; and Examine the relationship between multi-level barriers and medication adherence levels. A cross-sectional study included 130 adults (ages ≥ 18 years old) living with SCD who receive treatment/care from one of the 10 adult SCD clinics within the Networking California for sickle cell care initiative. Study measures included the medication adherence report scale (Professor Rob Horne), Beliefs about Medicine Questionnaire (Professor Rob Horne), and patient reported outcomes measurement information system. Participants reported barriers to medication adherence across 3 levels: Community-level barriers (e.g., COVID-19 pandemic); Institutional-level barriers (e.g., bad experiences with the health care system); and Individual-level barriers (e.g., beliefs and depression severity). Depression severity and patient concerns about SCD medication were inversely correlated with medication adherence (rs = -0.302, P < .001; rs = -0.341, P < .001 respectively). Patient beliefs about the necessity of SCD medication were insignificantly correlated with medication adherence (rs = 0.065, P = .464). Medication adherence was higher among patients who had fewer adherence barriers than multiple adherence barriers (Median medication adherence: fewer barriers = 22 vs multiple barrier = 20.50, P = .085), suggesting clinical significance although statistically insignificant. Identifying multi-level adherence barriers and examining their relationship with medication adherence will help develop targeted public health strategies to promote improved medication adherence and wellness among adults with SCD.

Hemoglobin and End-Organ Damage in Individuals with Sickle Cell Disease

Background

Sickle cell disease (SCD) is an inherited, chronic, multifaceted blood disorder. Patients with SCD develop anemia, which has been associated with end-organ damage (EOD).

Objectives

This retrospective, observational, repeated-measures study systematically characterizes the relationship between hemoglobin (Hb) level and EOD in adolescent and adult patients with SCD.

Methods

The study population comprised patients with SCD aged ≥12 years with available Hb data from a US provider-centric health care database. For each patient, each Hb value over time was included as a separate observation. Study outcomes-the onset of any new EOD, including chronic kidney disease, pulmonary hypertension, stroke, and leg ulcer-were ascertained during the 1-year period after each Hb assessment. The association between Hb levels and risk of new EOD was estimated using multivariable generalized estimating equations.

Results

A total of 16,043 unique patients with SCD contributed 44,913 observations. Adjusted odds of any EOD during the 1-year follow-up were significantly lower with higher Hb level. Risk reductions with higher Hb levels for chronic kidney disease, pulmonary hypertension, and leg ulcer were comparable. The risk of new EOD was significantly lower among adolescent and adult patients with higher Hb levels.

Conclusions

In patients with SCD, higher Hb levels are associated with a reduced risk of developing EOD. Therapeutic strategies that result in higher Hb levels may offer clinical and economic value for patients with SCD. (Curr Ther Res Clin Exp. 2023; 84:XXX-XXX).

Higher hydroxyurea adherence among young adults with sickle cell disease compared to children and adolescents

BACKGROUND

Sickle cell disease (SCD) results in severe complications, such as anaemia and pain episodes. Hydroxyurea (HU) is efficacious in SCD, yet adherence remains low.

OBJECTIVE

To assess the relationship of HU adherence to health care utilization and patients' characteristics.

METHODS

This is a 5-year retrospective chart review. Patients' demographics and medical history were collected from the electronic medical record (EMR). HU adherence was evaluated using foetal haemoglobin "HbF%", mean corpuscular volume "MCV", and absolute neutrophil count "ANC". Age groups included children (<12 years), adolescents (12-17 years), and young adults (≥18 years).

RESULTS

A total of 113 SCD patients on HU were included (median age 14 years, IQR 10-20; 50% female; 88% HbSS). Young adults had significantly higher HU adherence compared to adolescents and children, including higher median HbF% (24.2 vs. 12.4 vs. 8.6, p = .003), MCV (fl) (106.4 vs. 96.2 vs. 95.4, p = .01) and lower ANC (10³/ml) (3.25 vs. 4.9 vs. 4.2, p = .01), respectively. Patients with chronic pain had lower HU adherence (HbF% 15.3 vs. 10.7, p = .04; ANC 3.6 vs. 6.3, p = .002; MCV 102.3 vs. 93.1, p = .1). Patients with higher HbF or MCV and lower ANC had significantly less frequent emergency room visits (r_s=-0.26, p = .01; r_s=-0.23, p = .01; r_s=0.24, p = .01) and hospitalizations (r_s=-0.27, p = .01; r_s=-0.31, p = .01; r_s=0.21, p = .02) as well as shorter length of stays (r_s=-0.27, p = .0045; r_s=-.34, p = 0.004; r_s=0.23, p = .02), respectively. Similar trends in HU adherence and health care utilization were seen in subgroup analysis of only HbSS patients. There was no significant association of HU adherence to patients' sex, socio-economic status, distance from hospital, and HU duration.

CONCLUSIONS

Young adults with SCD had significantly higher HU adherence compared to children and adolescents. Patients with lower HU adherence and/or chronic pain had increased health care utilization. Future studies examining barriers to adherence and evaluating interventions to optimize HU adherence in SCD are warranted.KEY MESSAGESYoung adults with SCD had significantly higher HU adherence, as reflected in their laboratory markers, compared to children and adolescents.Patients with higher HU adherence and/or those without chronic pain had lower or less frequent health care utilization.No significant association of HU adherence to patients' sex, socio-economic status and distance from hospital.

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.

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.

Development and validation of the sickle cell stress scale-adult

Disease‐specific stress can partly explain Sickle Cell Disease (SCD) healthcare utilization. We developed and validated two measures of adult SCD‐specific stress for research and clinical care. A large cohort of adults with SCD completed both the 3‐item Likert‐scale adapted from a previous disease stress measure and a 10‐item Likert‐scale questionnaire drafted specifically to measure SCD stress. They concurrently completed a psychosocial and health‐related quality of life scale battery, then subsequently daily pain diaries. Diaires measured: daily intensity, distress and interference of pain; self‐defined vaso‐occlusive crises (VOC), opioid use, and types of healthcare utilization for up to 24 weeks. Analyses tested Cronbach's alpha, correlation of the three‐item and 10‐item stress scales with the concurrent battery, with percentages of pain days, VOC days, opioid use days, and healthcare utilization days, and correlation of baseline stress and 6‐month stress for the 10‐item scale. Cronbach's alpha was high for both the 3‐item (0.73) and 10‐item (0.83) SCD stress scales, test–retest correlation of 0.55, expected correlation with the concurrent battery, and correlation with diary‐measured healthcare utilization over 6 months. The correlations with the 3‐item scale were stronger, but only statistically significant for depression‐anxiety. The correlation between the two stress scales was 0.59. Both the 3‐item and the 10‐item stress scales exhibited good face, construct, concurrent, and predictive validity as well as moderate test–retest reliability. Further scale validation should determine population norms and response to interventions.

A Feasibility Pilot Study of Online Modules of Hydroxyurea and Sickle Cell Disease Care for Adolescents and Young Adults for Family Medicine Residents

Family medicine (FP) residency programs are located throughout Indiana, and most adults with sickle cell disease (SCD) in Indiana have access to a primary care clinic administered by a FP program. Allen County ranks third in SCD incidence in Indiana, but has few providers for adolescents, young adults (AYAs) and adults with SCD. Initiation of a novel partnership between Indianapolis-based adult hematologists (130 miles distant), and the FP program in Allen County aimed to educate FP residents about SCD, hydroxyurea, transition, and SCD complications. To determine the feasibility of utilizing online learning modules to educate FP residents about SCD care in AYA and adults, 3 online learning modules (comprehensive care of AYAs with SCD, hydroxyurea, and best practices in AYA transition) were developed and continuing medical education-accredited. Electronic pretest and posttest were distributed to 32 FP residents to test the retention of content through an Institutional Review Board approved protocol. This pilot study demonstrates that it is feasible to utilize online educational modules to educate providers about SCD care.

Incorporation of novel therapies for the management of sickle cell disease: A pharmacist's perspective

Patients with sickle cell disease (SCD) experience significant disease-related morbidity including multiorgan damage, chronic anemia, and debilitating pain crises. While hydroxyurea has been the primary disease modifying modality in SCD, novel therapies with unique mechanism of action have recently been approved. This review article examines the evidence surrounding the available SCD therapies to guide pharmacists on potential treatment selection and management strategies for patients with SCD. A systematic search of online databases was performed to identify literature on the management of SCD. While the newly approved novel agents have demonstrated clinical benefit it remains unclear how these agents fit into the treatment paradigm. Pharmacists should be aware of the data supporting the use of these novel agents to optimize use on a patient-specific basis.

Development and Validation of the Patient/Caregiver Reported Hydroxyurea Evaluation of Adherence for Life (HEAL) Scale

INTRODUCTION

Hydroxyurea reduces the incidence of vaso-occlusive episodes, stroke, and respiratory, cardiac, and renal damage in sickle cell disease by increasing fetal hemoglobin. However, because suboptimal adherence to hydroxyurea limits its effectiveness, understanding patient-specific barriers to hydroxyurea adherence could help improve adherence and health outcomes in patients with sickle cell disease. The aim of this single-site, prospective, IRB-approved study was to validate a 24-item patient- and caregiver-reported hydroxyurea treatment adherence questionnaire, the Hydroxyurea Evaluation of Adherence for Life (HEAL) scale.

METHODS

A sample of 24 adults with sickle cell disease and 16 caregivers of children with sickle cell disease completed the HEAL scale, and a subset of the original sample provided a second HEAL scale for test-retest reliability. HEAL scale results were validated against global adherence ratings from participants and health-care providers, records of access to pill bottles, and laboratory values for fetal hemoglobin and absolute neutrophil count.

RESULTS AND DISCUSSION

Results demonstrated excellent internal consistency for the HEAL Total score and eight (3-item) subscale scores (Dose, Remember, Plan, Cost, Understand, Effectiveness, Laboratory, and Pharmacy), as well as strong test-retest reliability for all HEAL scores except the Cost subscale. HEAL Total scores correlated significantly with validity measures, including global adherence ratings and lab values. The HEAL scale offers significant clinical potential for understanding adherence in individual sickle cell disease patients and significant research potential for characterizing adherence in persons with sickle cell disease who are treated with hydroxyurea.

Utilization of Hydroxyurea Among Patients Diagnosed with Sickle Cell Disease in Jazan, Saudi Arabia

PURPOSE

The early diagnosis of sickle cell disease (SCD) patients and getting appropriate treatment are crucial for improving clinical outcomes. This study aims to assess the use of hydroxyurea among patients diagnosed with SCD and assess factors influencing the attitude toward the medication and the reasons for discontinuation.

METHODS

This study was a cross-sectional investigation targeting parents or caregivers of children diagnosed with SCD in the Jazan region of Saudi Arabia. Data were collected from tertiary healthcare hospitals via a self-administered questionnaire. The questionnaire was composed of sections measuring the participants' demographics, the number of children diagnosed with SCD, the use of hydroxyurea, and the parents' beliefs about hydroxyurea.

RESULTS

There were 301 parents or caregivers recruited. The majority of the recruited participants were mothers (54.5%), and nearly half of the sample were older than 35. More than 80% of the participants declare that one or more of their children are receiving hydroxyurea to manage SCD. The majority of participants declared that using hydroxyurea reduced the frequency of body pain episodes, emergency department visits, and hospital admissions. Participants' major concern about the use of hydroxyurea was related to the fear of weakening their immunity (29.5%) and hydroxyurea's perceived effect on fertility (16.8%). Furthermore, 52 (18%) of the participants declared that the use of hydroxyurea to manage the disease was stopped; the main reasons for stopping was their belief that hydroxyurea had side effects and its impact on weakening of their immune system.

CONCLUSION

The findings indicate the importance of increasing the role of clinicians in educating patients and caregivers about the use of hydroxyurea and its benefits.

Barriers and Facilitators of Use of Hydroxyurea among Children with Sickle Cell Disease: Experiences of Stakeholders in Tanzania

Factors contributing to low use of HU among SCD patients exist in high-income countries. The latter leaves a drift of literature on factors for low utilization of HU in developing countries. This study aimed to explore the factors influencing the use of HU in the management of SCD in Tanzania. A qualitative study was employed to interview purposively selected participants for this study. The in-depth interviews were conducted with 11 parents of children with SCD, four medical doctors working at sickle cell clinics, and two representatives of the national health insurance fund (NHIF). Interviews were audio-recorded, transcribed, and thematically analysed. Barriers identified were misconception of parents on SCD, financial constraints, regulatory restrictions, worries and fears of medical doctors on the acceptability of HU, shortages of laboratory equipment and consumables, and limited availability of HU. Adequate knowledge of the parents and medical doctors on SCD and HU and opportunities for HU accessibility were the facilitators identified. The utilization of HU by the individual with SCD is affected by several factors, from individual to policy level. Nevertheless, parents of children with SCD and medical doctors working in sickle cell clinics demonstrated good knowledge of the diseases and HU.

Sickle cell disease in sub-Saharan Africa: transferable strategies for prevention and care

Sickle cell disease can be life-threatening or chronically debilitating for both children and adults. Worldwide, more than 300 000 children are born with sickle cell disease every year, over 75% of whom in sub-Saharan Africa. Increased awareness and early interventions, such as neonate screening and comprehensive care, have led to considerable reductions in mortality in children younger than 5 years in high-income countries. However, sickle cell disease prevention and care have largely been neglected in Africa. Without intervention, 50-90% of affected children in many sub-Saharan African countries die before their fifth birthday. Fortunately, increasing initiatives in sub-Saharan Africa are piloting interventions such as neonate screening and comprehensive care, and as mortality declines, quality of life and increased life expectancy become major targets for interventions. Hydroxyurea (hydroxycarbamide) and haematopoietic stem-cell transplantation have already been shown to be effective therapies in high-income countries, but are either not widely accessible or too expensive for most African populations. These challenges are being alleviated by numerous networks evolving through international collaborations that are positively changing the outlook of sickle cell disease management in sub-Saharan Africa. In this Series paper, we describe the epidemiology, pathophysiology, clinicobiological profile, and psychosocial effects of sickle cell disease in sub-Saharan Africa. We highlight transferable strategies already used for the successful management of the condition and key strategies and recommendations for affordable and comprehensive care on the continent. TRANSLATION: For the French translation of the abstract see Supplementary Materials section.

A Needs Assessment of Persons With Sickle Cell Disease in a Major Medical Center in North Carolina

BACKGROUND Sickle cell disease (SCD) is a complex disease associated with many complications and a shortened lifespan. In 2016, the National Heart, Lung and Blood Institute funded 8 centers in the United States to form the Sickle Cell Disease Implementation Consortium, with the goal of improving SCD care. The aim of our study was to describe SCD self-efficacy, pain interference, and barriers to care from the perspective of persons with SCD in the North Carolina center.METHODS Persons with SCD, aged 15 and older were recruited from a large SCD center in North Carolina. Surveys, focus groups, and interviews were completed.RESULTS Fifty-one people completed a survey, and 14 people completed an interview or focus group. Barriers identified in the survey included self-care barriers, misconceptions related to hydroxyurea (an oral medication that reduces rates of pain crisis), limited provider knowledge, and stigma. Concerning self-efficacy, participants reported that they were able to manage their pain symptoms most of the time. Pain interfered most with the ability to participate in social and day-to-day activities.Common themes from the focus groups and interviews included misconceptions about hydroxyurea, pain, provider knowledge, stigma, co-management, transportation, and insurance. Recommendations to improve care included the use of case managers, utilization of treatment guidelines, individualized pain protocols, and effective co-management by providers.LIMITATIONS Participants were recruited from 1 SCD center and may not be representative of the entire SCD population in North Carolina.CONCLUSIONS Participants described many perceived barriers to care, and their responses suggest a need for improvements in patient hydroxyurea education, provider knowledge, and care coordination.

Intentional and unintentional nonadherence to hydroxyurea among people with sickle cell disease: a qualitative study

Hydroxyurea is an efficacious treatment for sickle cell disease (SCD), but adoption is low among individuals with SCD. The objective of this study was to examine barriers to patients' adherence to hydroxyurea use regimens by using the intentional and unintentional medication nonadherence framework. We interviewed individuals with SCD age 15 to 49.9 years who were participants in the Sickle Cell Disease Implementation Consortium (SCDIC) Needs Assessment. The intentional and unintentional medication nonadherence framework explains barriers to using hydroxyurea and adds granularity to the understanding of medication adherence barriers unique to the SCD population. In total, 90 semi-structured interviews were completed across 5 of the 8 SCDIC sites. Among interviewed participants, 57.8% (n = 52) were currently taking hydroxyurea, 28.9% (n = 26) were former hydroxyurea users at the time of the interview, and 13.3% (n = 12) had never used hydroxyurea but were familiar with the medication. Using a constructivist grounded theory approach, we discovered important themes that contributed to nonadherence to hydroxyurea, which were categorized under unintentional (eg, Forgetfulness, External Influencers) and intentional (Negative Perceptions of Hydroxyurea, Aversion to Taking Any Medications) nonadherence types. Participants more frequently endorsed adherence barriers that fell into the unintentional nonadherence type (70%) vs intentional nonadherence type (30%). Results from this study will help SCD health care providers understand patient choices and decisions as being either unintentional or intentional, guide tailored clinical discussions regarding hydroxyurea therapy, and develop specific, more nuanced interventions to address nonadherence factors.

Digital behavioural interventions for people with sickle cell disease

This is a protocol for a Cochrane Review (intervention). The objectives are as follows: To identify and assess the effects of digital behavioural interventions focused on behavioural change in people with SCD on: medication adherence or disease management (such as managing acute and chronic pain), or both, on health- and other-related outcomes;specific subgroups defined by age (i.e. children, adolescents and adults) and type of modality or delivery (e.g. cell phone, the Internet).

Adherence to hydroxyurea, health-related quality of life domains and attitudes towards a smartphone app among Irish adolescents and young adults with sickle cell disease

Introduction

SCD patients experience declines in health-related quality of life (HRQOL) domains compared with healthy controls. Despite evidence supporting the benefits of hydroxyurea, medication non-adherence remains problematic, especially in adolescents and young adults (AYA). Adherence barriers include forgetfulness and lack of knowledge. Recently, increased interest in technology-based strategies to improve medication adherence has emerged. No data currently exists on hydroxyurea adherence, HRQOL or perceptions of technology-based tools in the Irish SCD population.

Methods

In order to interrogate these domains among Irish AYA SCD patients we administered an anonymous survey at two tertiary referral centres in Dublin, Ireland, in July 2019.

Results

Sixty-three patients participated; 63% female and 37% male, with a median and mean age of 17 and 19 years, respectively. Average monthly adherence was 76% using a visual analogue scale. Recall barriers were present in 62% while 26% omit hydroxyurea for reasons other than forgetting. Reviewing HRQOL; only 36.5% felt always physically able to engage in recreational activities, while 51% experienced disruption to school/college/work due to pain. Eighty-one percent reported that anxiety about health interferes with their lives and non-adherence correlated with worse HRQOL outcomes. Interest in a smartphone app was expressed by the majority, with daily medication reminders being the most popular feature. Sharing adherence data with doctors and discussion forums were less appealing.

Conclusions

Representing over 10% of the Irish SCD population, our survey provides novel and valuable insights into medication adherence and HRQOL domains. Preferred app features may inform future technology-based interventions to improve medication adherence in SCD and other chronic health conditions.

Changing the Clinical Paradigm of Hydroxyurea Treatment for Sickle Cell Anemia Through Precision Medicine

Sickle cell anemia (SCA) is a common and devastating inherited blood disorder, affecting millions of people across the world. Without treatment, SCA results in tremendous morbidity and early mortality. Hydroxyurea is the primary and most well-established pharmacologic therapy with proven benefits to ameliorate the clinical course of SCA, primarily due to its ability to increase the expression of fetal hemoglobin (HbF), which prevents sickling of red blood cells. The optimal induction of HbF depends upon selection and maintenance of the proper dose that maximizes benefits and minimizes toxicity. Due to the significant interpatient variability in hydroxyurea pharmacokinetics, pharmacodynamics, and dosing, most patients treated with hydroxyurea receive suboptimal doses and have only modest treatment responses. Recognizing this variability, using a precision medicine approach, we developed and prospectively evaluated an individualized dosing model for children with SCA, designed to optimize the hydroxyurea dose and clinical response. We utilize novel laboratory methods and a sparse sampling strategy requiring only 10 μL of blood collected 15 minutes, 60 minutes, and 180 minutes after a test dose. We use Bayesian adaptive control to estimate hydroxyurea exposure and to select an individual, optimal starting dose. This dosing model has resulted in HbF responses >30-40%, levels beyond what is achieved with traditional weight-based dosing and trial and error dose escalation. This hydroxyurea dosing strategy, if widely implemented, has the potential to change the treatment paradigm of hydroxyurea therapy and improve outcomes for the millions of patients with SCA across the world.

Integration of Mobile Health Into Sickle Cell Disease Care to Increase Hydroxyurea Utilization: Protocol for an Efficacy and Implementation Study

BACKGROUND

Hydroxyurea prevents disease complications among patients with sickle cell disease (SCD). Although its efficacy has been endorsed by the National Health Lung and Blood Institute evidence-based guidelines, its adoption is low, both by patients with SCD and providers. Mobile health (mHealth) apps provide benefits in improving medication adherence and self-efficacy among patients with chronic diseases and have facilitated prescription among medical providers. However, mHealth has not been systematically tested as a tool to increase hydroxyurea adherence nor has the combination of mHealth been assessed at both patient and provider levels to increase hydroxyurea utilization.

OBJECTIVE

This study aims to increase hydroxyurea utilization through a combined two-level mHealth intervention for both patients with SCD and their providers with the goals of increasing adherence to hydroxyurea among patients and improve hydroxyurea prescribing behavior among providers.

METHODS

We will test the efficacy of 2 mHealth interventions to increase both patient and provider utilization and knowledge of hydroxyurea in 8 clinical sites of the NHLBI-funded Sickle Cell Disease Implementation Consortium (SCDIC). The patient mHealth intervention, InCharge Health, includes multiple components that address memory, motivation, and knowledge barriers to hydroxyurea use. The provider mHealth intervention, Hydroxyurea Toolbox (HU Toolbox), addresses the clinical knowledge barriers in prescribing and monitoring hydroxyurea. The primary hypothesis is that among adolescents and adults with SCD, adherence to hydroxyurea, as measured by the proportion of days covered (the ratio of the number of days the patient is covered by the medication to the number of days in the treatment period), will increase by at least 20% after 24 weeks of receiving the InCharge Health app, compared with their adherence at baseline. As secondary objectives, we will (1) examine the change in health-related quality of life, acute disease complications, perceived health literacy, and perceived self-efficacy in taking hydroxyurea among patients who use InCharge Health and (2) examine potential increases in the awareness of hydroxyurea benefits and risks, appropriate prescribing, and perceived self-efficacy to correctly administer hydroxyurea therapy among SCD providers between baseline and 9 months of using the HU Toolbox app. We will measure the reach, adoption, implementation, and maintenance of both the InCharge Health and the HU Toolbox apps using the reach, effectiveness, adoption, implementation, and maintenance framework and qualitatively evaluate the implementation of both mHealth interventions.

RESULTS

The study is currently enrolling study participants. Recruitment is anticipated to be completed by mid-2021.

CONCLUSIONS

If this two-level intervention, that is, the combined use of InCharge Health and HU Toolbox apps, demonstrates efficacy in increasing adherence to hydroxyurea and prescribing behavior in patients with SCD and their providers, respectively, both apps will be offered to other institutions outside the SCDIC through a future large-scale implementation-effectiveness study.

TRIAL REGISTRATION

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

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/16319.

Development of the InCharge Health Mobile App to Improve Adherence to Hydroxyurea in Patients With Sickle Cell Disease: User-Centered Design Approach

Background

Sickle cell disease (SCD) is an inherited blood disorder causing acute complications and chronic progressive end organ damage. SCD is associated with significant morbidity, early mortality, impaired health-related quality of life, and increased acute health care utilization. Hydroxyurea is a US Food and Drug Administration–approved medication that reduces disease complications, acute health care utilization, and costs. However, adherence to hydroxyurea is suboptimal. Mobile health (mHealth) interventions have the potential to improve hydroxyurea adherence, but few examples exist that are specific to the SCD population.

Objective

This study aimed to design a mHealth intervention for individuals with SCD to improve adherence to hydroxyurea, using a user-centered design that was informed by specific barriers to hydroxyurea adherence and utilization in this population.

Methods

This study consisted of 4 phases. In phase 1, individuals with SCD and health care providers participated in an optimization digital workshop. In phase 2, patients completed surveys pertaining to their interest in mHealth use, barriers and facilitators to hydroxyurea use, and health literacy. Phases 3 and 4 involved semistructured interviews and focus groups, respectively, and used the Health Belief Model (HBM) as the framework to investigate drivers of poor hydroxyurea adherence and to inform the development of an app prototype. In addition, in phase 4, we have incorporated the patients’ feedback on the preliminary app prototype and its features.

Results

Barriers to hydroxyurea adherence were consistent with the literature and included forgetfulness and several specific thoughts and emotions associated with hydroxyurea use (eg, fear of side effects, depression, stigma, and hopelessness). In addition, more than half of the participants reported potentially low health literacy. Preferred patient app features included 7 key components, namely (1) medication reminders and tracker, (2) disease education, (3) communication, (4) personalization, (5) motivation, (6) support during pain episodes, and (7) social support. Utilizing a user-centered design approach, data obtained from patients and providers were translated into features within the app, mapping to components of the HBM and the specific drivers of hydroxyurea adherence and matching the literacy level of the population, resulting in the development of a novel mobile app called InCharge Health.

Conclusions

The InCharge Health app is an mHealth intervention developed with substantial input from users and by mapping the HBM as the framework that guided the choice for its components. InCharge Health is a customized product for the SCD population aimed at optimizing medication adherence, with the end goal of improving quality of life and health outcomes among patients with SCD. The efficacy and implementation of the InCharge Health app as an mHealth intervention to promote hydroxyurea adherence will be tested in a future stepped-wedge multicenter trial for adolescents and adults with SCD.

Impact of Medicaid expansion on access and healthcare among individuals with sickle cell disease

PURPOSE

Sickle cell disease (SCD) is associated with high acute healthcare utilization. The purpose of this study was to examine whether Medicaid expansion in California increased Medicaid enrollment, increased hydroxyurea prescriptions filled, and decreased acute healthcare utilization in SCD.

METHODS

Individuals with SCD (≤65 years and enrolled in Medicaid for ≥6 total calendar months any year between 2011 and 2016) were identified in a multisource database maintained by the California Sickle Cell Data Collection Program. We describe trends and changes in Medicaid enrollment, hydroxyurea prescriptions filled, and emergency department (ED) visits and hospital admissions before (2011-2013) and after (2014-2016) Medicaid expansion in California.

RESULTS

The cohort included 3635 individuals. Enrollment was highest in 2014 and lowest in 2016 with a 2.8% annual decease postexpansion. Although <20% of the cohort had a hydroxyurea prescription filled, the percentage increased by 5.2% annually after 2014. The ED visit rate was highest in 2014 and decreased slightly in 2016, decreasing by 1.1% annually postexpansion. Hospital admission rates were similar during the pre- and postexpansion periods. Young adults and adults had higher ED and hospital admission rates than children and adolescents.

CONCLUSIONS

Medicaid expansion does not appear to have improved enrollment or acute healthcare utilization among individuals with SCD in California. Future studies should explore whether individuals with SCD transitioned to other insurance plans or became uninsured postexpansion, the underlying reasons for low hydroxyurea utilization, and the lack of effect on hospital admissions despite a modest effect on ED visits.

Pharmacy hydroxyurea education materials for patients with sickle cell disease: An environmental scan and assessment of accuracy

BACKGROUND

Hydroxyurea (HU) remains a cornerstone of sickle cell disease (SCD) therapy; however, its use is limited by poor patient adherence owing to concerns about side effects. Pharmacies routinely provide patients with handouts about HU, which, we hypothesized, contain inaccuracies that may contribute to negative patient perceptions of HU.

METHODS

We used a systematic approach to collect and review patient information handouts (PIHs) on HU from pharmacies in Ontario, Canada. PIHs were evaluated according to: i. Number of inaccurate statements, ii. Percentage of essential statements based on comparison with a reference standard PIH developed by the Canadian Haemoglobinopathy Association (CanHaem), and iii. Reading level.

RESULTS

PIHs were collected from 98% of chain and community pharmacies registered in Ontario. All PIHs contained inaccurate statements, most frequently relating to the risk of developing cancer. Only 33% of PIHs identified SCD as an indication for HU use. Pharmacy PIHs contained 45% of the essential statements present within the CanHaem HU PIH, neglecting to mention use of HU for management of SCD and benefits of HU in preventing SCD complications. Moreover, the reading level across pharmacy PIHs was 1.8 grades higher than that advised for written patient education materials.

CONCLUSION

Patients who are prescribed HU are likely to be provided with PIHs that contain inaccuracies that are weighted toward the risks of HU therapy and run contrary to published literature. This study identifies a gap in the care of patients with SCD and an opportunity to improve the quality of HU PIHs to help patients make well-informed decisions about their health.

Sickle-Cell Disease Co-Management, Health Care Utilization, and Hydroxyurea Use

BACKGROUND

Sickle-cell disease (SCD) causes significant morbidity, premature mortality, and high disease burden, resulting in frequent health care use. Comanagement may improve utilization and patient adherence with treatments such as Hydroxyurea. The purpose of this study was to describe acute-care utilization in Medicaid-enrolled patients with SCD, patient factors associated with comanagement, and adherence to Hydroxyurea.

METHODS

Data from 2790 patients diagnosed with SCD, age 1 to 65+ years, enrolled at least 1 month in North Carolina Medicaid between March 2016 and February 2017, were analyzed. Outpatient visits were categorized as primary care, hematologist, and nonhematologist specialist. Nurse practitioners or physician assistants with unidentified specialty type or family practice were categorized separately. Comanagement was defined as a minimum of 1 primary care and 1 hematologist visit/patient during the study period.

RESULTS

There were notable age-related differences in utilization of health care services. Only 34.82% of the sample was comanaged. Comanagement was higher in the 1-to-9-year-old (44.88%) and 10-to-17-year-old groups (39.22%) versus the 31-to-45-year-old (30.26%) and 65+-year-old (18.75%) age groups. Age had the greatest influence (AUC = 0.599) on whether or not a patient was comanaged. Only a third of the sample (32.24%) had at least 1 Hydroxyurea (HU) prescription. Age was the most predictive factor of good HUadherence (AUC = 0.6503). Prediction by comanagement was minimal with an AUC = 0.5615.

CONCLUSION

Comanagement was a factor in predicting HUadherence, but further studies are needed to identify the frequency and components of comanagement needed to increase adherence and reduce acute care utilization.

Comparative Effectiveness of a Web-Based Patient Decision Aid for Therapeutic Options for Sickle Cell Disease: Randomized Controlled Trial

Background

Hydroxyurea, chronic blood transfusions, and bone marrow transplantation are efficacious, disease-modifying therapies for sickle cell disease but involve complex risk-benefit trade-offs and decisional dilemma compounded by the lack of comparative studies. A patient decision aid can inform patients about their treatment options, the associated risks and benefits, help them clarify their values, and allow them to participate in medical decision making.

Objective

The objective of this study was to develop a literacy-sensitive Web-based patient decision aid based on the Ottawa decision support framework, and through a randomized clinical trial estimate the effectiveness of the patient decision aid in improving patient knowledge and their involvement in decision making.

Methods

We conducted population decisional needs assessments in a nationwide sample of patients, caregivers, community advocates, policy makers, and health care providers using qualitative interviews to identify decisional conflict, knowledge and expectations, values, support and resources, decision types, timing, stages and learning, and personal clinical characteristics. Interview transcripts were coded using QSR NVivo 10. Alpha testing of the patient decision aid prototype was done to establish usability and the accuracy of the information it conveyed, and then was followed by iterative cycles of beta testing. We conducted a randomized clinical trial of adults and of caregivers of pediatric patients to evaluate the efficacy of the patient decision aid.

Results

In a decisional needs assessment, 223 stakeholders described their preferences, helping to guide the development of the patient decision aid, which then underwent alpha testing by 30 patients and 38 health care providers and iterative cycles of beta testing by 87 stakeholders. In a randomized clinical trial, 120 participants were assigned to either the patient decision aid or standard care (SC) arm. Qualitative interviews revealed high levels of usability, acceptability, and utility of the patient decision aid in education, values clarification, and preparation for decision making. On the acceptability survey, 72% (86/120) of participants rated the patient decision aid as good or excellent. Participants on the patient decision aid arm compared to the SC arm demonstrated a statistically significant improvement in decisional self-efficacy (P=.05) and a reduction in the informed sub-score of decisional conflict (P=.003) at 3 months, with an improvement in preparation for decision making (P<.001) at 6 months. However, there was no improvement in terms of the change in knowledge, the total or other domain scores of decisional conflicts, or decisional self-efficacies at 6 months. The large amount of missing data from survey completion limited our ability to draw conclusions about the effectiveness of the patient decision aid. The patient decision aid met 61 of 62 benchmarks of the international patient decision aid collaboration standards for content, development process, and efficacy.

Conclusions

We have developed a patient decision aid for sickle cell disease with extensive input from stakeholders and in a randomized clinical trial demonstrated its acceptability and utility in education and decision making. We were unable to demonstrate its effectiveness in improving patient knowledge and involvement in decision making.

Trial Registration

ClinicalTrials.gov NCT03224429; https://clinicaltrials.gov/ct2/show/NCT03224429 and ClinicalTrials.gov NCT02326597; https://clinicaltrials.gov/ct2/show/NCT02326597

Innovations in Targeted Anti-Adhesion Treatment for Sickle Cell Disease

Sickle cell disease (SCD) is an inherited hemoglobinopathy that leads to significant lifetime morbidity and early mortality. An enhanced understanding of the complex pathophysiology of the disease has elucidated novel therapeutic targets for which new therapies are in development. In order to increase the therapeutic landscape, it has been important to identify the blood vessel and more specifically the endothelium as the target organ in this complex disease. Through this lens, we present a review of new anti-adhesion therapies for SCD in development. The long-term promise of multimodal therapies for SCD is finally on the horizon.

The Role of Patient-Physician Communication on the Use of Hydroxyurea in Adult Patients with Sickle Cell Disease

OBJECTIVE

This qualitative study analyzed the perspective of patients living with sickle cell disease (SCD) on their process of deciding whether to take hydroxyurea (HU), and the role of physician communication in patients' decision-making process.

METHODS

From October 2015 to July 2016, we conducted semi-structured interviews among patients with SCD (N = 20) that were audio-recorded and transcribed. Participants were ≥ 18 years old, a patient of an urban adult sickle cell center, able to provide informed consent, and English-speaking. We iteratively developed codes and used thematic analysis to organize the key themes.

RESULTS

Most participants were female (65%), middle aged (M = 44, SD = 12.2), and 55% were prescribed HU for an average of 10.4 (SD = 4.7) years. Participants described 3 key factors that influenced their decision regarding HU treatment: (1) lifestyle, (2) health status, and (3) HU characteristics. Four themes emerged about provider communication and HU treatment decisions: (1) provider's advisement, (2) shared decision-making, (3) "wrestled," and (4) not feeling heard.

CONCLUSION

Providers who engaged in shared decision-making empowered participants to decide whether to start HU treatment. Participants who felt their providers were not listening to their concerns expressed disengaging from HU treatment. During discussions about HU with patients living with SCD, providers must understand the multi-faceted aspects that impact patients' decision and empower patients to engage in such discussions. Further research is needed to understand the role of shared decision-making among patients with SCD to improve management of SCD.

Hydroxyurea: Pattern of Use, Patient Adherence, and Safety Profile in Patients with Sickle Cell Disease in Oman

OBJECTIVES

Many barriers contribute to the underutilization of hydroxyurea (HU) in the treatment of sickle cell disease (SCD), and adherence to its use is often reported to be suboptimal. It is important to have information on the safety of HU in patients with SCD. Our study assessed the pattern of use, patients' adherence to medication, discontinuation of use, and safety of HU in patients with SCD.

METHODS

This cross-sectional study was conducted in the department of medicine of a referral hospital in Oman over five months and included a review of patient files and patient interview. Approval was obtained from the Regional Research and Ethics Committee of the A'Dakhiliyah Governorate and the hospital administration. The parameters were compared between groups using the chi-square test.

RESULTS

Of 298 patients studied, 128 (43.0%) had used HU at some points. The difference in the prevalence of HU use was statistically significant based only on age (p = 0.014), with younger patients more likely to be currently using HU or used HU in the past. The majority of patients were adherent (82.5%) based on self-reported adherence. The prevalence of discontinuation (temporary or permanent) of HU use was high (57.0%), and suspected adverse drug reaction (ADR) was the most common reason. Among those who had never used HU, 33.7% of patients had an indication for the initiation of HU. A quarter of patients who used HU developed a suspected ADR, with blood abnormalities being the commonest. The duration of HU use influenced ADR prevalence (p = 0.015).

CONCLUSIONS

Among the current users of HU, the majority of the patients were adherent based on self-reported medication adherence. The prevalence of discontinuation of HU use and instances of non-initiation of HU among those indicated were high. A larger study, ideally of a prospective nature, in various governorates of Oman, would provide a wider picture at the national level.

From trust to skepticism: An in-depth analysis across age groups of adults with sickle cell disease on their perspectives regarding hydroxyurea

Despite its efficacy, the uptake of HU in adults with sickle cell disease (SCD) is poor likely due to a combination of system, provider, and patient-related factors. We investigated attitudes of adult patients towards HU by conducting qualitative interviews with 95 adult SCD patients (age 18 to 67 years old, 71 were female). While 53% of all participants reported that they were currently taking HU, patients ranging in age 18–30 years (Group 1) were more likely to report current HU use as compared to those (Group 2) ranging in age 31–67 years (65% vs. 41% P = 0.01). Most Group 1 participants who reported currently taking HU indicated that the decision to start HU was made by a parent, though some made the decision themselves as a young adult. Group 1 participants expressed trust in the efficacy of HU as well as trust that their physician adequately shared risks and benefits for the medication. The Group 2 participants, who were not currently on HU, were skeptical that all the risks and benefits of HU were known, were concerned that the efficacy of HU was not proven, and that they were not receiving complete information about its potential side effects. Of Group 2 participants who reported currently being on HU, 25% were concerned about the side effects and efficacy of HU and reported continuing HU because of a lack of effective alternatives. These data suggest that there are significant differences by age in adult SCD patients’ attitudes towards, utilization and understanding of the risks and benefits of HU.

Beliefs about hydroxyurea in youth with sickle cell disease

BACKGROUND

Hydroxyurea reduces complications and improves health-related quality of life (HRQOL) in sickle cell disease (SCD) patients, however adherence remains suboptimal. Understanding patients' views of hydroxyurea is critical to optimize adherence, particularly in adolescents and young adults (AYA). Study objectives were to assess beliefs about hydroxyurea using the Beliefs about Medicines Questionnaire (BMQ), and to examine the relationship of patients' beliefs to their hydroxyurea adherence and HRQOL.

METHODS

Thirty-four AYA with SCD participated in a cross-sectional study January-December 2015. Study assessments included BMQ to examine beliefs about hydroxyurea; Visual Analogue Scale (VAS) to assess hydroxyurea adherence; and Patient Reported Outcomes Measurement Information System (PROMIS®) to evaluate HRQOL.

RESULTS

Participants (41% female, 91% Black) had median age of 13.5 (IQR 12-18) years. Participants' concerns about overuse of medications correlated with concerns about hydroxyurea (r_s = 0.36, p = 0.04) and overall harm of medications (r_s = 0.5, p = 0.003). Participants' age positively correlated with the necessity of hydroxyurea (r_s = 0.45, p = 0.007). Participants' concerns about hydroxyurea and overuse of medications positively correlated with anxiety (r_s = 0.41, p = 0.02; r_s = 0.44, p = 0.01) and depression (r_s = 0.37, p = 0.04; r_s = 0.54, p = 0.001), but inversely correlated with peer relationships (r_s = -0.45, p = 0.03; r_s = -0.44, p = 0.03), respectively, suggesting better HRQOL with concerns. Fifty percent of participants reported low hydroxyurea adherence (VAS < 80%), which was more seen in patients with higher concerns about hydroxyurea (p = 0.02).

CONCLUSIONS

Beliefs about hydroxyurea correlated with HRQOL scores and adherence levels. Addressing patients' concern about hydroxyurea and medications overall as well as routine assessment of adherence and beliefs could help to overcome adherence barriers.

Randomized feasibility trial to improve hydroxyurea adherence in youth ages 10-18 years through community health workers: The HABIT study

INTRODUCTION

The main therapeutic intervention for sickle cell disease (SCD) is hydroxyurea (HU). The effect of HU is largely through dose-dependent induction of fetal hemoglobin (HbF). Poor HU adherence is common among adolescents.

METHODS

Our 6-month, two-site pilot intervention trial, "HABIT," was led by culturally aligned community health workers (CHWs). CHWs performed support primarily through home visits, augmented by tailored text message reminders. Dyads of youth with SCD ages 10-18 years and a parent were enrolled. A customized HbF biomarker, the percentage decrease from each patients' highest historical HU-induced HbF, "Personal best," was used to qualify for enrollment and assess HU adherence. Two primary outcomes were as follows: (1) intervention feasibility and acceptability and (2) HU adherence measured in three ways: monthly percentage improvement toward HbF Personal best, proportion of days covered (PDC) by HU, and self-report.

RESULTS

Twenty-eight dyads were enrolled, of which 89% were retained. Feasibility and acceptability were excellent. Controlling for group assignment and month of intervention, the intervention group improved percentage decrease from Personal best by 2.3% per month during months 0-4 (P = 0.30), with similar improvement in adherence demonstrated using pharmacy records. Self-reported adherence did not correlate. Dyads viewed CHWs as supportive for learning about SCD and HU, living with SCD and making progress in coordinated self-management responsibility to support a daily HU habit. Most parents and youth appreciated text message HU reminders.

CONCLUSIONS

The HABIT pilot intervention demonstrated feasibility and acceptability with promising effect toward improved medication adherence. Testing in a larger multisite intervention trial is warranted.

Adherence to hydroxyurea, health-related quality of life domains, and patients' perceptions of sickle cell disease and hydroxyurea: a cross-sectional study in adolescents and young adults

Background

Sickle cell disease (SCD) patients have impaired domains of health-related quality of life (HRQOL). Hydroxyurea is safe and efficacious in SCD; however, adherence is suboptimal, and patients’ perceptions are poorly understood amongst adolescents and young adults (AYA). Study objectives were to: (1) examine patients’ perceptions of SCD and hydroxyurea; and (2) explore the relationship of their perceptions to clinical characteristics, HRQOL domains and hydroxyurea adherence.

Methods

Thirty-four SCD patients on hydroxyurea (≥6 months) participated in a single-institution study. Study measures included Brief-Illness Perceptions Questionnaire, ©Modified Morisky Adherence Scale 8-items, and Patient Reported Outcomes Measurement Information System (PROMIS®). We assessed the relationship of patients’ perceptions to hydroxyurea adherence using Wilcoxon rank-sum test, the number of hospitalizations using Kruskal-Wallis test, and the number of ED visits, adherence level, HRQOL domain scores using Spearman’s rho correlations. We conducted a sub-analysis in HbSS patients to evaluate the relationship of patients’ perceptions to laboratory markers of hydroxyurea adherence.

Results

Participants were 59% male and 91% Black, and had a median age of 13.5 (range 12–18) years. Participants with ≥4 hospitalizations over 1-year prior (using electronic medical chart review) reported more negative perceptions of SCD-related symptoms and emotional response, and perceived hydroxyurea as less beneficial; all p-values ≤0.01. Most participants (74%) reported low hydroxyurea adherence. Participants with higher hydroxyurea adherence perceived more hydroxyurea benefits (r_s = 0.44, p < 0.01) and had better emotional response to SCD (r_s = −0.44, p = 0.01). In a sub-analysis of HbSS patients, perceived benefits of hydroxyurea positively correlated with HbF (r_s = 0.37, p = 0.05) and MCV values (r_s = 0.35, p = 0.05). Participants with more negative perceptions of SCD-related consequences, concerns, and emotional response, and fewer perceived hydroxyurea benefits reported worse fatigue (r_s = 0.68; r_s = 0.44; r_s = 0.74; r_s = −0.60), pain (r_s = 0.56; r_s = 0.54; r_s = 0.63; r_s = −0.39), anxiety (r_s = 0.55; r_s = 0.58; r_s = 0.56; r_s = −0.47), and depression (r_s = 0.64; r_s = 0.49; r_s = 0.70; r_s = −0.62), respectively, all p-values <0.05.

Conclusions

Dynamics influencing hydroxyurea adherence are multifactorial, and understanding patients’ perceptions is critical to overcoming adherence barriers. Patients’ favorable perceptions correlated with greater adherence and better HRQOL domain scores. Prospective evaluation of patients’ perceptions of SCD and hydroxyurea in relation adherence, HRQOL domains and clinical outcomes is warranted.

Barriers to hydroxyurea adherence and health-related quality of life in adolescents and young adults with sickle cell disease

OBJECTIVES

To identify barriers to hydroxyurea adherence (negative beliefs, access, and/or recall barriers), and their relationship to adherence rates and health-related quality of life (HRQOL) among adolescents and young adults (AYA) with sickle cell disease (SCD).

METHODS

A cross-sectional survey was administered to 34 AYAs (12-22 years old) in SCD clinics from January to December 2015. Study measures included Brief Medication Questionnaire, Modified Morisky Adherence Scale 8-items, visual analog scale, and Patient Reported Outcomes Measurement Information System.

RESULTS

Participants (59% male; 91% Black) had a median age of 13.5 years (IQR 12-18). Participants reported negative beliefs (32%), recall barriers (44%), and access barriers (32%). Participants with recall barriers reported worse pain (P=.02), fatigue (P=.05), and depression (P=.05). The number of adherence barriers inversely correlated with adherence level using ©MMAS-8 (r_s =-.38, P=.02) and VAS_dose (r_s =-.25, P=.14) as well as MCV (r_s =-.45, P=.01) and HbF% (r_s =-.36, P=.05), suggesting higher hydroxyurea adherence in patients with fewer barriers.

CONCLUSIONS

Patients with fewer barriers to hydroxyurea adherence were more likely to have higher adherence rates and better HRQOL scores. Routine assessment of hydroxyurea adherence and its related barriers could provide actionable information to improve adherence rates, HRQOL, and other clinical outcomes.

Hydroxyurea therapy for children with sickle cell disease: describing how caregivers make this decision

Background

Hydroxyurea (HU) is underutilized in children with sickle cell disease (SCD) because caregivers frequently decline HU when it is offered. This study explores what impacts this decision.

Results

Caregivers of children with clinically severe SCD whose children were offered HU previously were interviewed. We used a qualitative analytical approach to analyze their telephone interview transcripts. Caregivers who chose HU (n = 9) reported their children had severe SCD, sought detailed information about HU, and accepted HU as a preventative therapy. In contrast, caregivers who did not choose HU (n = 10) did not perceive their children as having severe SCD and did not question their child’s provider about HU.

Conclusions

This study identifies specific areas that providers should address to when they discuss HU with families so that they can make informed decisions. Our study also uncovered factors that are important to consider when designing future interventions to improve hydroxyurea acceptance and when developing decision-aid tools to assist caregivers of children with SCD who are considering disease modifying therapies.

The LSD1 inhibitor RN-1 induces fetal hemoglobin synthesis and reduces disease pathology in sickle cell mice

Inhibition of lysine-specific demethylase 1 (LSD1) has been shown to induce fetal hemoglobin (HbF) levels in cultured human erythroid cells in vitro. Here we report the in vivo effects of LSD1 inactivation by a selective and more potent inhibitor, RN-1, in a sickle cell disease (SCD) mouse model. Compared with untreated animals, RN-1 administration leads to induced HbF synthesis and to increased frequencies of HbF-positive cells and mature erythrocytes, as well as fewer reticulocytes and sickle cells, in the peripheral blood of treated SCD mice. In keeping with these observations, histologic analyses of the liver and spleen of treated SCD mice verified that they do not exhibit the necrotic lesions that are usually associated with SCD. These data indicate that RN-1 can effectively induce HbF levels in red blood cells and reduce disease pathology in SCD mice, and may therefore offer new therapeutic possibilities for treating SCD.

Immune parameter analysis of children with sickle cell disease on hydroxycarbamide or chronic transfusion therapy

Sickle cell disease (SCD) is increasingly appreciated as an inflammatory condition associated with alterations in immune phenotype and function. In this cross-sectional study we performed a multiparameter analysis of 18 immune markers in 114 paediatric SCD patients divided by treatment group [those receiving hydroxycrabamide (HC, previously termed hydroxyurea), chronic transfusion (CT), or no disease-modifying therapy] and 29 age-matched African American healthy controls. We found global elevation of most immune cell counts in SCD patients receiving no disease-modifying therapy at steady state. Despite the decrease in percentage of haemoglobin S associated with CT therapy, the abnormal cellular immune phenotype persisted in patients on CT. In contrast, in both univariate and multivariate analysis, treatment with HC was associated with normalization of the vast majority of leucocyte populations. This study provides additional support for HC treatment in SCD, as it appears that HC decreases the abnormally elevated immune cell counts in patients with SCD.

Do difficulties in swallowing medication impede the use of hydroxyurea in children?

BACKGROUND

Use of hydroxyurea (HU) in children with sickle cell disease (SCD) may be hampered by its formulation as a capsule and the limited availability of liquid HU.

PROCEDURE

At four Pediatric SCD clinics, parents of children with SCD ages 5-17 years were surveyed about their children's medication use and ability to swallow medication. Data were stratified by HU therapy and analyzed using descriptive statistics, Chi square tests, Fisher exact tests and univariate analysis.

RESULTS

Of the 116 parents surveyed, 97% were the primary caregiver. One fourth (26%) of parents reported that their child's difficulty swallowing medication interfered with daily medication use. Age-related differences were found in ability to swallow medication, but not by HU use. Children taking HU were more likely to take multiple daily medications, with more frequent dosing schedules. Among 65 HU users, children using the liquid formulation (28%, n = 18) were younger than capsule users (P < 0.0001). Nonetheless, half of liquid HU users were aged 8-13. Children using liquid HU were more likely to have difficulties swallowing medication than those who use HU capsules (OR 4.29, 95% CI 1.14-16.18, P = 0.032). Few had received training for swallowing medication.

CONCLUSIONS

One fourth of surveyed parents viewed swallowing as challenging to daily medication use. These findings suggest that difficulty swallowing capsules is a fairly frequent barrier to for children prescribed HU, especially for younger children. HU use appears more likely in families with daily and more complex medication schedules. Coaching for swallowing capsules may improve HU utilization and adherence.

Parental and other factors associated with hydroxyurea use for pediatric sickle cell disease

BACKGROUND

Hydroxyurea (HU) is highly effective treatment for sickle cell disease (SCD). While pediatric use of HU is accepted clinical practice, barriers to use may impede its potential benefit.

PROCEDURE

A survey of parents of children ages 5-17 years with SCD was performed across five institutions to assess factors associated with HU use.

RESULTS

Of the 173 parent responses, 65 (38%) had children currently taking HU. Among parents of children not taking HU, the most commonly cited reasons were that their hematology provider had not offered it, their child was not sufficiently symptomatic and concerns about potential side effects. Even parents of HU users reported widespread concern about effectiveness, long-term safety, and off-label use. In bivariate analyses, children's ages, parental demographics such as education level, or travel time to their hematology provider were not correlated with HU use. Bivariate analysis and multivariate logistic regression revealed three significant factors associated with current HU use: better parental knowledge about its major therapeutic effects (P < 0.001), sickle genotype (P = 0.005), and institution of clinical care (P = 0.04).

CONCLUSIONS

Pervasive concerns about HU safety exist, even among parents of current users. Varying knowledge among parents appears to be independent of their demographics, and is associated with HU use. Inter-institutional variability in parental knowledge and drug uptake highlights potentially potent site-specific influences on likelihood of HU use. Overall, these survey data underscore the need for strategies to bolster parental understanding about benefits of HU and address concerns about its safety.

High resource hospitalizations among children with vaso-occlusive crises in sickle cell disease

BACKGROUND

Vaso-occlusive crises (VOCs) contribute to frequent hospitalizations among children with sickle cell disease (SCD). The objective of this study was to identify factors associated with high resource utilization during hospitalizations for VOC.

PROCEDURE

We analyzed pediatric discharges 0-18 years of age with a primary diagnosis of SCD with crisis from the 2006 Kids' Inpatient Database, a nationally representative sample of pediatric hospital discharges. High resource hospitalizations were defined as those in the highest decile for total charges. We conducted sample-weighted regression analyses to determine associations between independent variables (patient demographics, hospital characteristics, illness severity) and high resource use.

RESULTS

There were 9,893 (0.371%) discharges for children with VOCs. Median total hospitalization charges were $10,691. In multivariate analysis, children 15-18 years of age (odds ratio [OR] 3.39, 95% confidence interval [CI] 2.54-4.53), 10-14 years of age (OR 2.72, 95% CI 2.07-3.59), and 5-9 years of age (OR 1.74, 95% CI 1.30-2.34) had higher odds of high resource hospitalizations compared to children 0-4 years of age. Care in a children's hospital had three times the odds of high resource use compared to care in a general hospital. Discharges with secondary diagnoses including pneumonia (OR 2.46, 95% CI 1.96-3.09) and constipation (OR 1.78, 95% CI 1.31-2.40) were also associated with high resource use.

CONCLUSIONS

Older age and secondary diagnoses were associated with high resource use during VOC hospitalizations. These findings suggest the need to improve adherence to comprehensive care among older children to prevent VOCs and standardize protocols to manage VOC complications.

Assessment of the in vivo genotoxicity of new lead compounds to treat sickle cell disease

The compounds 1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)methyl nitrate (C1), (1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)ethyl nitrate (C2), 3-(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)benzyl nitrate (C3), 4-(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)-N-hydroxy-benzenesulfonamide (C4), 4-(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)benzyl nitrate (C5), and 2-[4-(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)phenyl]ethyl nitrate (C6) were evaluated with a micronucleus test using mouse peripheral blood to identify new candidate drugs for the treatment of sickle cell disease (SCD) that are safer than hydroxyurea. The compounds induced an average frequency of micronucleated reticulocytes (MNRET) of less than six per 1,000 cells at 12.5, 25, 50, and 100 mg/kg, whereas hydroxyurea induced an average MNRET frequency of 7.8, 9.8, 15, and 33.7 per 1000 cells respectively, at the same concentrations. Compounds C1-C6 are new non-genotoxic in vivo candidate drugs for the treatment of SCD symptoms.