Targeted Hydroxyurea Education after an Emergency Department Visit Increases Hydroxyurea Use in Children with Sickle Cell Anemia

Sickle cell disease and infertility risks: implications for counseling and care of affected girls and women

INTRODUCTION

Sickle cell disease (SCD), its treatments and cures present infertility risks. Fertility counseling is broadly indicated for affected girls and women and fertility preservation may appeal to some. Several streams of evidence suggest that the reproductive lifespan of women with SCD is reduced. Pregnancy is associated with high miscarriage rates. There are enduring questions about the effects of highly effective hydroxyurea treatment on female fertility. Current conditioning regimens for gene therapy or hematopoietic stem cell transplant are gonadotoxic. Fertility preservation methods exist as non-experimental standards of care for girls and women. Clinicians are challenged to overcome multifactorial barriers to incorporate fertility counseling and fertility preservation care into routine SCD care.

AREAS COVERED

Here we provide a narrative review of existing evidence regarding fertility and infertility risks in girls and women with SCD and consider counseling implications of existing evidence.

EXPERT OPINION

Addressing fertility for girls and women with SCD requires engaging concerns that emerge across the lifespan, acknowledging uncertainty and identifying barriers to care, some of which may be insurmountable without public policy changes. The contemporary SCD care paradigm can offer transformative SCD treatments alongside comprehensive counselling that addresses fertility risks and fertility preservation opportunities.

Adherence to hydroxyurea and clinical outcomes among children with sickle cell anemia

OBJECTIVE

Hydroxyurea lowers the incidence of vaso-occlusive pain crises (VOC) and acute chest syndrome (ACS) among children with sickle cell anemia (SCA). Our objective was to assess the relationship between levels of adherence to hydroxyurea and clinical outcomes among children and adolescents with SCA.

METHODS

This retrospective cohort study included Medicaid data (2005-2012) from Florida, Illinois, Louisiana, Michigan, South Carolina, and Texas. The study population consisted of children 1-17 years old with SCA enrolled in Medicaid for 3 years. Among children that initiated hydroxyurea, the medication possession ratio (MPR) was calculated as the proportion of days covered by hydroxyurea. Six months after initiation of hydroxyurea, clinical outcomes were assessed through the end of the study period: numbers of VOC-related inpatient admissions and emergency department visits, and encounters for ACS. Multivariable Poisson models were used to predict outcomes by MPR quartile adjusting for previous healthcare utilization, state, and age.

RESULTS

Hydroxyurea was initiated by 515 children. The median MPR was 0.53 (interquartile range = 0.3-0.8). The annual median number of visits was 0.0 for ACS, 1.3 for VOC-related emergency department, and 1.4 for VOC-related inpatient admissions. For each outcome, the highest quartile of MPR had the lowest predicted count; this difference was significant for ACS visits when compared with the lowest quartile of MPR.

CONCLUSION

This study demonstrated a high level of adherence (>75%) was essential to achieve a lower incidence of common negative clinical outcomes. Further, moderate and severe hydroxyurea nonadherence may be more common than previously appreciated among children, emphasizing the importance of developing and testing innovative strategies to increase adherence.

Knowledge of fertility and perception of fertility treatment among adults with sickle cell disease (KNOW FERTILITY)

Introduction

This study assessed fertility knowledge in adults with sickle cell disease using the Cardiff Fertility Knowledge Scale and Fertility Treatment Perception Survey and compared knowledge scores in respondents with sickle cell disease to previously reported unaffected cohorts.

Methods

This cross-sectional study surveyed adults over age 18 with sickle cell disease at an adult sickle cell disease center using a 35-question survey addressing infertility risk factor knowledge and perceptions of fertility treatment. Analyses included summary statistics for continuous and categorical variables, univariate linear regression, and Mann-Whitney U tests for group comparisons of Fertility Knowledge Scale scores. Fertility Treatment Perception Survey scores were measured by medians of the two positive statements and four negative statements to generate separate positive and negative treatment belief scores. Statistical significance was set at p < 0.05 for all analyses.

Results

Ninety-two respondents (71 female, 21 male) with median age of 32 years (IQR: 25.0, 42.5) completed the survey between October 2020-May 2021. Sixty-five percent of respondents reported taking sickle cell disease treatment and 18% reported refusing at least one sickle cell disease treatment due to fertility concerns. The mean Fertility Knowledge Score was 49% (SD: 5.2), lower than reported in an international cohort (57% vs. 49%, p = 0.001), and higher than in a cohort of reproductive-aged Black women in the USA (49% vs. 38%, p = 0.001). Less than 50% of respondents correctly identified common infertility risk factors including sexually transmitted infections, advanced age, and obesity. Mean positive fertility perception score was 3 (IQR 3, 4), and negative fertility perception score was 3.5 (IQR 3, 4). Factors associated with agreement with negative fertility perception statements included: trying to conceive, refusing sickle cell disease treatment, and undergoing fertility treatment.

Discussion

Opportunities exist to improve knowledge of infertility risk factors among adults with sickle cell disease. This study raises the possibility that nearly one in five adults with sickle cell disease refuse SCD treatment or cure due to infertility concerns. Education about common infertility risks factors needs to be addressed alongside disease- and treatment- associated fertility risks.

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.

Real-Life experience with hydroxyurea in patients with sickle cell disease: Results from the prospective ESCORT-HU cohort study

Several controlled studies have evidenced good efficacy and short-term and mid-term safety profiles for hydroxyurea (HU), which has become the cornerstone for prevention of sickle-cell disease (SCD)-related vaso-occlusive crises. However, there are few large-scale reports on its long-term use and certain caregivers and patients have concerns about its safety. Following the licensing of HU in Europe for children and adults with severe forms of SCD, ESCORT-HU was designed as a Phase IV observational cohort study. It included 1906 participants, of whom 55% were adults. The most common hemoglobin (Hb) genotypes were HbSS (84.7%) and HbSβ+ (7.0%). The median duration of follow-up was 45 months, for a total of 7309 patient-years of observation. The dose of HU after 1 year was 20.6 mg/kg/d for children and 16.3 mg/kg/d for adults. There was a statistically significant decrease in the number of vaso-occlusive episodes lasting >48 h, acute chest syndrome episodes, hospitalizations, and the percentage of patients requiring blood transfusions within the first 12 months relative to the year before enrolment. Neutropenia and thrombocytopenia were the most commonly reported adverse effects. No new HU toxicity was identified. Overall, 125 pregnancies were reported in 101 women and no malformations were observed in the neonates. There were 12 pregnancies for partners of male patients treated with HU. One case of fatal myelodysplastic syndrome was reported, for which a causal association with HU could not be excluded. This cohort study of patients with SCD highlights the positive benefit-to-risk ratio of HU in children and adults.

Screening for new red blood cell alloantibodies after transfusion in patients with sickle cell disease

BACKGROUND

Patients with sickle cell disease (SCD) are frequent recipients of red blood cell (RBC) transfusions and are at risk for RBC alloimmunization. RBC alloimmunization is diagnosed by identifying RBC alloantibodies as part of pre-transfusion testing, but this testing fails to detect alloantibodies that have evanesced. It may be beneficial to screen for new RBC alloantibody development after transfusion before possible antibody evanescence.

STUDY DESIGN AND METHODS

Our institution started a new initiative for episodically transfused patients with SCD to obtain at least one antibody screen 2-6 months after transfusion as part of their clinical care. A database was created to prospectively track all transfused patients for 1 year and their post-transfusion antibody screen results. Patients received prophylactically CEK-matched RBC units.

RESULTS

During the study year, 138 patients with SCD received a total of 242 RBC transfusions. Patients with a history of an RBC alloantibody (n = 13, 9.4%) had previously received more RBC units than non alloimmunized patients (median 11 vs. 2 RBC units, p = .0002). A total of 337 post-transfusion antibody screens were obtained in 127 patients (92.0%) with 110 patients (79.7%) having at least one antibody screen 2-6 months post-transfusion. With this prospective testing, two new RBC alloantibodies (anti-C and -M) were identified in two patients.

CONCLUSION

It is feasible to test for new RBC alloantibody development in most episodically transfused patients with SCD as part of their routine care. The yield of this screening appears low with CEK matching, but it could still provide important information for individual patients.

Efficient Clinical Counseling for Sickle Cell Disease

Sickle cell anemia (SCA) is a chronic illness that requires frequent health care visits for preventative management. Adherence to national guidelines such as the National Heart Lung and Blood Institute (NHLBI) Expert Panel Report on the Evidence-Based Management of Sickle Cell Disease can be challenging to both the clinician and the patient. Utilizing effective communication strategies with patients and their families can improve clinician/patient relationships, as well as adherence to national guidelines. Aims of this overview are to review challenges faced in outpatient subspecialty medicine and describe evidence-based techniques for more effective communication for patients with sickle cell anemia.

Transcranial Doppler Screening Adherence among Children with Sickle Cell Anemia Seen in the Emergency Department

OBJECTIVE

To evaluate adherence to annual transcranial Doppler ultrasound (TCD) screening to prevent stroke among patients with sickle cell anemia (SCA) seen in the emergency department (ED).

STUDY DESIGN

This retrospective chart review included patients with SCA seen at a large pediatric ED over 64 weeks. Patients who did not need a TCD (age <2 or ≥16 years, on chronic transfusions, history of an inadequate TCD) or were not followed at the study institution were excluded. Patients who had received a TCD in the last 12 months (TCD adherent) were compared with patients who had not (TCD nonadherent).

RESULTS

During the study period, 257 patients with SCA in need of an annual TCD were identified and 63 patients (25%) had not received an annual TCD, including 19 patients (7%) who had never had a TCD. All TCD adherent patients had a clinic visit in the last year compared with 75% of TCD nonadherent patients, P < .0001. The mean interval time since the last hematology clinic appointment from the ED encounter was greater for the TCD nonadherent group: 70 vs 270 days, P < .0001. Demographics including markers of socioeconomic status were not significantly different between the 2 groups.

CONCLUSIONS

Patients with SCA who present to the ED and are nonadherent to TCD screening guidelines are less likely to have had a recent hematology clinic visit. Future interventions to improve screening for stroke in SCA should target this patient population seen in the ED but not clinic.

Inpatient Ordering of Home Hydroxyurea by Residents for Hospitalized Patients With Sickle Cell Disease

BACKGROUND

Hydroxyurea is a well-established disease-modifying medication for sickle cell disease (SCD). At some institutions, hydroxyurea can only be ordered by "chemotherapy-certified" providers which may not include pediatric resident physicians.

METHODS

We conducted a survey of 39 American pediatric hospitals regarding their policy on resident hydroxyurea ordering for SCD. Our institution changed its policy in June 2016 to allow residents to order hydroxyurea for hospitalized patients with SCD who were already on hydroxyurea at home. We conducted a retrospective review of the medical records of a random sample of patients with SCD on hydroxyurea admitted the year before and the year after this policy change.

RESULTS

In our national survey, 51% of surveyed hospitals allowed residents to order hydroxyurea, 19% required a second signature, and 30% did not allow residents to order hydroxyurea. In our institutional study, patients after the policy change were significantly more likely to have received their home hydroxyurea by hospital day 1: before 62/90 (69%) versus after 105/119 (88%), P=0.0005. The proportion of patients who inappropriately received hydroxyurea was very low in both groups: before 1/91 (1%) versus after 3/126 (2%), P=0.64, with no serious adverse clinical events due to inappropriate hydroxyurea administration.

CONCLUSIONS

Considerable national variation in practice currently exists in regards to resident hydroxyurea ordering hospital policies. A policy allowing residents to order hydroxyurea significantly increased the likelihood of a patient receiving hydroxyurea while hospitalized with no significant increase in inappropriate hydroxyurea administration. Resident hydroxyurea ordering seems safe and beneficial.

Hydroxyurea Initiation Among Children With Sickle Cell Anemia

This study assesses characteristics of children with sickle cell anemia associated with hydroxyurea initiation. Medicaid administrative claims from 6 states (2005-2012) were used to identify children with sickle cell anemia enrolled in Medicaid for ≥2 years. Hydroxyurea use was defined as >30 days' supply of filled prescriptions. Children were classified as initiators (no use in year 1; use in year 2) or nonusers (no use in either year). Logistic regression was used to estimate associations between initiation, health care encounters, and demographics. A total of 4435 children were enrolled for 2 years during the study period; 885 (20.0%) initiators and 3080 (69.4%) nonusers. Children had an annual mean of 2.0 sickle cell disease-related inpatient admissions (SD = 2.2), 8.2 sickle cell disease-related outpatient visits (SD = 7.2), and 3.6 emergency department visits (SD = 3.5). The odds of initiating hydroxyurea increased with increasing health care utilization, age, and calendar year (all P values <.05).