Home Medication Delivery: Measuring Med Compliance in Pediatrics with Sickle Cell Disease
Authors: Okonkwo Philomena C , Hua Brian , Gonzalez Alicia , Joy Maria , Shah Gunjan , Hsu Lewis L 
Published: June 2024

Abstract

Presentation Date: 6/9/2024
Presentation Start Time: 3:15:00 PM

Background
The American Society of Hematology (ASH) recommendations for management of sickle cell disease (SCD) emphasize starting prescription medications in early childhood to modify the disease course. However, access barriers like transportation, long pharmacy wait-times, cost concerns, and complex medication regimens can hinder medication adherence and subsequently impact desired patient outcomes. Published reports on medication adherence in pediatric SCD prior to 2020 found Medication Possession Ratio (MPR) ranged from 49% to 74% for hydroxyurea. Deferasirox iron chelation MPR has been reported at 44% for pediatric SCD and beta thalassemia. MPR &gt; 80% for hydroxyurea is associated with positive outcomes in SCD. The COVID pandemic further impaired medication adherence, and clinic follow up. A tertiary medical center adapted its pharmacy services in 2020 to address the challenges in medication adherence.
A home medication delivery service was introduced through a Specialty Pharmacy unit (SP) in April 2020 to ensure patients, such as pediatric SCD patients, could access their medications during COVID isolation. Clinical pharmacists also made regular telephone contact with families. SP has continued these services after COVID restrictions were relaxed.
This retrospective study evaluates how the service offered by SP affects medication adherence and follow-up visit compliance among its pediatric SCD population.

Methods
This retrospective quality assessment was conducted in January 2024. The inclusion criteria were SCD patients aged 0 to 20 years old who utilized UI Health SP’s home medication delivery service for at least one chronic disease-modifying medication between 2020 and 2023. Data were collected by SP clinical pharmacy team on the following four medications managed by the SP: Hydroxyurea, Voxelotor, L- glutamine and Deferasirox film-coated tablets.
Quantitative data was collected by a retrospective chart review of medication delivered, clinic appointments kept, and laboratory monitoring fetal hemoglobin (HbF) and Mean Corpuscular Volume (MCV) results. The SP pharmacists assessed medication compliance based on dispense history and scheduled mail order medication refills to calculate MPR. They used a daily calendar to monitor patients’ schedules for home delivery. Noncompliance was identified if patients missed three or more medication refills within one year.
Qualitative data were collected from the family caregivers by questionnaires and interviews conducted via telephone or face-to-face sessions at the pediatric sickle cell clinic.

Results
A total of 81 pediatric SCD patients met eligibility criteria, although 8 had some gaps in use of SP. Participants were taking either one or two of the study medications. Each medication was studied from April 2020 to December 2023. Of these patients, 39 were male (48%). About 90% reside in the same county as the tertiary med center.
Medication Possession Ratio: Among eligible pediatric SCD patients, Siklos Hydroxyurea had perfect compliance, with MPR 100% (n = 14). Hydroxyurea suspension showed a high MPR of 91.75% (n = 36), indicating good adherence among most patients. L-glutamine had MPR 87% (n = 22) and voxelotor 87.3% (n = 8), also indicating relatively good adherence. However, Deferasirox had the lowest compliance rate at 75% (n = 2).
Lab response: Good compliance with Hydroxyurea had the expected increase in their HbF and MCV levels for those with genotypes SS and S-beta-zero-thalassemia (n = 78). The three with genotype SC and did not show any increase in their HbF levels.

Qualitative Results
Participants generally agreed that the service made medication management easier, minimized ED visits and hospitalization, and overall reduced the possibility of SCD complications. Strong follow-up by the team of pharmacy staff and clinicians was noted to be one of the measures that improved compliance.

Conclusions
Overall, service through SP is associated with MPR over the benchmark 80% associated with improved SCD patient outcomes for hydroxyurea. These MPR rates are like the results reported from other interventions to enhance medication adherence in SCD. MPR challenges remains with medications like Deferasirox.
Although the study is a quality assessment rather than a randomized trial, these findings suggest that the Specialty Pharmacy’s tailored interventions and ongoing support do optimize medication adherence in pediatric SCD patients compared to simply dispensing prescriptions for families to pick up. The home medication delivery service has potential to address access barriers. Future work could build these collaborations with Specialty Pharmacies to ensure comprehensive care for pediatric SCD patients and mitigate the impact of this chronic condition on their health and well-being.