Hydroxyurea Adherence for Personal Best in Sickle Cell Treatment: HABIT (HABIT)

The investigators propose that culturally aligned community-based interventions in our multi-ethnic sickle cell disease (SCD) population, augmented by task-focused communication technology, can improve self-managed adherence to hydroxyurea (HU) by decreasing barriers to use, supporting parent-youth partnerships for chronic disease self-management and reinforcing the behavior of daily medication use. Culturally aligned community health workers (CHW) are a well-established means to support chronic disease self-management by underserved families, in partnership with medical homes. CHWs can identify and address multiple barriers and reinforce developmentally appropriate self-management to help youth reach and maintain their best fetal hemoglobin (HbF) levels. However, this strategy alone may be insufficient to achieve daily HU adherence. The investigators therefore propose a feasibility trial to test the feasibility and acceptability of a structured intervention of CHW support to address existing barriers to improve HU use, augmented by daily cue-based parent and youth text message reminders, to efficiently extend CHW family support and reinforce family partnerships for self-management.

Sickle cell disease (SCD) is an inherited disorder affecting the blood and causes anemia, painful sickle crises, organ damage, reduced quality of life and high health care use. Hydroxyurea (HU) is an oral medication that reduces disease symptoms and improves quality of life by increasing the amount of fetal hemoglobin in the blood. Despite the clinical promise of hydroxyurea, many children with SCD do make taking hydroxyurea a daily health habit. General barriers to medication adherence in underserved populations include lack of trust of medical staff, incomplete knowledge regarding benefits of hydroxyurea, and other factors that impede access to care such as transportation difficulties. Challenges specific to hydroxyurea use include understanding the importance of maximizing fetal hemoglobin levels and addressing concerns about hydroxyurea. Children and adolescents also require that a developmentally appropriate transition of self-management be established with their parents. Community-based health workers are a well established means to provide support for chronic disease management for underserved families and address multi-faceted barriers through culturally, behaviorally and developmentally aligned intervention. The investigators hypothesize that Community Health Workers support, augmented by daily task-focused communication technology, can improve self-managed adherence to hydroxyurea.

Sickle cell disease, Medication adherence, Hydroxyurea, Community health worker intervention, Sickle Cell Treatment

Community Health Workers will have scheduled interactions with subjects and will customize text messaging jointly with each youth and parent and initiate text message reminders to both parent and youth for months 4-6.

Those randomized to the Education group will continue usual care, and will be provided with educational materials about sickle cell disease and hydroxyurea use for children.

CHWs will have scheduled interactions with subjects at home, by telephone or at Community League of the Heights (CLOTH), our partner community-based organization (CBO). CHWs will customize text messaging jointly with each youth and parent (Month 3) and text message reminders to both parent and youth will be implemented during Months 4-6. Subjects lacking a mobile phone or sufficient cell phone plan will be compensated to purchase or upgrade plans to accommodate texts.

Dyads randomized to the control group will continue usual clinic-based care, including monitoring and review of HbF levels, and similar frequency of clinic visits and access to sickle cell team staff. They will be provided with educational materials about sickle cell disease and hydroxyurea use for children.

In this feasibility study, feasibility will be assessed of our methods, the impact of the intervention on adherence to hydroxyurea, and the ability to retain subjects throughout the 6 month period. These data will be used to calculate the effect size of the intervention to estimate the sample needed for a larger trial.

The investigators will estimate the effect size of the intervention on youth-parent communication about self-management responsibility by assessing quantitative changes in questionnaires administered to both parents and youth.

The investigators will estimate the effect size of the intervention on youth-parent communication about quality of life by assessing quantitative changes in in general pediatric and Sickle Cell disease Quality of Life questionnaires administered to both parents and youths.

The investigators will estimate the effect size of the intervention on youth-parent communication about resource use, such as urgent outpatient appointments, emergency room visits, hospitalizations, missed days from school and parent productivity by assessing quantitative changes in questionnaires administered to parents.

Inclusion Criteria: Youth: Sickle type - homozygous sickle disease or sickle-beta thalassemia disease Age 10 to 18 years Currently prescribed hydroxyurea (HU) ≥18 months (for assessing historical hydroxyurea adherence and identify personal best) ≥3 fetal hemoglobin assessments over past 12 months with pre-HbF ≥10% below historical personal best value Youth has/uses cell phone with text message capability Youth able to speak/read English or Spanish. Youth willing to participate Parent: Parent/legal guardian meets all inclusion criteria Parent/guardian speaks/reads English or Spanish Parent/ legal guardian willing to participate Family expected to reside in community for ≥ 1 years Exclusion Criteria: Youth: A different sickle type Youth < 10 years of age or ≥ 18 years of age Youth not prescribed hydroxyurea, or on chronic transfusions <3 fetal hemoglobin assessments over past 12 months Sexually active female ≥11 not using reliable contraception (due to hydroxyurea teratogenic risk) Pregnancy Cognitive impairment (>1 level below expected grade) Youth not residing with parent/legal guardian Sibling of a youth enrolled in this study Parent: Parent/legal guardian is not the primary caregiver Youth in foster care

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