title: Electronic measurement of compliance with mercaptopurine in pediatric patients with acute lymphoblastic leukemia.
abstract: Twenty-four pediatric patients with acute lymphoblastic leukemia (ALL) on maintenance therapy were evaluated for their compliance with taking their prescribed doses of oral mercaptopurine (6-MP).
  
  
  RESULTS
  We utilized the Medication Event Monitoring System (MEMS; Aprex Corporation, Fremont, CA) for the study. Compliance was defined as the number of days doses were taken as a percentage of the total number of days doses were prescribed during the study period. The mean age of the patients was 7.3 years (range 2.6-17.2 (years). Patients were evaluated for a mean of 44 days (range 15-94 days). Thirty-three percent of patients (8) took less than 90% and 17% (4) took less than 80% of their prescribed pills. Eight patients were also evaluated for a difference in compliance between morning and evening administration. For the comparison of compliance between a morning vs. an evening schedule a tren toward improved compliance in the evening was found. Five patients had an increase and one patient a decrease in compliance with an evening schedule (differences ranged from 0.2% to 51.3%), with two patients having 100% compliance on both schedules.
  
  
  CONCLUSIONS
  Our data raise concern that a significant proportion of pediatric patients are non-compliant with pill taking and demonstrate that the timing of administration of 6-MP in children with ALL may be crucial in some patients and supports the hypothesis that evening administration of 6-MP is associated with a lower risk of relapse.
authors.affiliation: Division of Hematology/Oncology, University of Toronto, Canada.
authors.forename: R C
authors.initials: RC
authors.lastname: Lau
authors.forename: D
authors.initials: D
authors.lastname: Matsui
authors.forename: M
authors.initials: M
authors.lastname: Greenberg
authors.forename: G
authors.initials: G
authors.lastname: Koren
mesh_terms: D000293:Adolescent; D000964:Antimetabolites, Antineoplastic / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D003201:Computers; D005260:Female; D006801:Humans; D008297:Male; D015122:Mercaptopurine / Q000627:therapeutic use*; D010349:Patient Compliance; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000188:drug therapy*
chemical_list: D000964:Antimetabolites, Antineoplastic; D015122:Mercaptopurine