Comparison of self-report and electronic monitoring of 6MP intake in childhood ALL: a Children’s Oncology Group study

Abstract

• Self-report overestimated electronically monitored 6MP adherence at least some of the time in a large majority of patients (84.4%).• Nonadherers were more likely to overreport 6MP intake (47%) compared with adherent patients (8%).Adequate exposure to oral 6-mercaptopurine (6MP) during maintenance therapy for childhood acute lymphoblastic leukemia (ALL) is critical for sustaining durable remissions; accuracy of self-reported 6MP intake is unknown. We aimed to directly compare self-report to electronic monitoring (Medication Event Monitoring System [MEMS]) and identify predictors of overreporting in a cohort of 416 children with ALL in first remission over 4 study months (1344 patient-months for the cohort) during maintenance therapy. Patients were classified as "perfect reporters" (self-report agreed with MEMS), "overreporters" (self-report was higher than MEMS by ‡5 days/month for ‡50% of study months), and "others" (not meeting criteria for perfect reporter or overreporter). Multivariable logistic regression examined sociodemographic and clinical characteristics, 6MP dose intensity, TPMT genotype, thioguanine nucleotide levels, and 6MP nonadherence (MEMS-based adherence <95%) associated with the overreporter phenotype; generalized estimating equations compared 6MP intake by self-report and MEMS. Self-reported 6MP intake exceeded MEMS at least some of the time in 84% of patients. Fifty patients (12%) were classified as perfect reporters, 98 (23.6%) as overreporters, 2 (0.5%) as underreporters, and 266 (63.9%) as others. In multivariable analysis, the following variables were associated with the overreporter phenotype: non-white race: Hispanic, odds ratio (OR), 2.4, P 5 .02; Asian, OR, 3.1, P 5 .02; African American, P < .001; paternal education less than college (OR, 1.4, P 5 .05);

Area deprivation is associated with poorer overall survival in children with acute lymphoblastic leukemia

“…Socioeconomically disadvantaged families may find these burdens especially difficult to bear, and this could cause differential delays, lapses, or nonadherence to therapy. This hypothesis is supported by data indicating that sociodemographic factors including non‐White race and lower parental education are associated with poorer 6‐mercaptopurine adherence during maintenance chemotherapy 41,42 . In our analysis, census tracts in nonmetropolitan areas tended to be classified as more disadvantaged.…”

Applying the COM‐B model to patient‐reported barriers to medication adherence in pediatric acute lymphoblastic leukemia

“…In our study, the rate of nonadherence measured by the MMAS-8 for patients is higher than what has been reported previously. 8,[10][11][12]17 Hispanic and adolescent patients have higher rates of nonadherences. 10,46 The strength of our study is the diverse patient population, which is reflective of ALL patients treated at our center.…”

“…and high (8). 34,35 In our study, we dichotomized MMAS-8 into adherent (score 8; high adherence) and nonadherent (score < 8; low and moderate).…”

Oral Medication Adherence Among Adolescents and Young Adults with Cancer Before and Following Use of a Smartphone-Based Medication Reminder App

“…11 Phenotypic patterns of self-reported compared with electronically monitored adherence have been described among children and adolescents receiving 6-mercaptopurine therapy during maintenance therapy for acute lymphoblastic leukemia. 15 Participants with ''over-reporter'' phenotypes, those whose self-reported adherence was greater than that identified through electronic cap monitoring for q15 days/month for q50% of monitored months, were more likely to have suboptimal adherence. Further identification and description of adherence phenotypes may define subgroups that may benefit from a given intervention.…”