Objective versus subjective assessment of oral medication adherence in pediatric inflammatory bowel disease

✍ Scribed by Kevin A. Hommel; Christine M. Davis; Robert N. Baldassano

• Publisher: John Wiley and Sons
• Year: 2009
• Tongue: English
• Weight: 93 KB
• Volume: 15
• Category: Article
• ISSN: 1078-0998
• DOI: 10.1002/ibd.20798

✦ Synopsis

Background:

The objective was to examine the prevalence and frequency of oral medication nonadherence using a multimethod assessment approach consisting of objective, subjective, and biological data in adolescents with inflammatory bowel disease (IBD).

Methods: Medication adherence was assessed via pill counts, patient/parent interview, and 6-thioguanine nucleotide (6-TGN)/6methylmercaptopurine nucleotide (6-MMPN) metabolite bioassay in 42 adolescents with IBD. Pediatric gastroenterologists provided disease severity assessments.

Results:

The objective nonadherence prevalence was 64% for 6-MP/azathioprine (AZA) and 88% for 5-aminosalicylate (5-ASA) medications, whereas subjective nonadherence prevalence was 10% for 6-MP/AZA and 2% for 5-ASA. The objective nonadherence frequency was 38% for 6-MP/AZA and 49% for 5-ASA medications, and subjective nonadherence frequency was 6% for 6-MP/ AZA and 3% for 5-ASA. The bioassay data revealed that only 14% of patients had therapeutic 6-TGN levels.

Conclusions:

The results indicate that objectively measured medication nonadherence prevalence is consistent with that observed in other pediatric chronic illness populations, and that objective nonadherence frequency is considerable, with 40%-50% of doses missed by patients. Subjective assessments appeared to overestimate adherence. Bioassay adherence data, while compromised by pharmacokinetic variation, might be useful as a cursory screener for nonadherence with follow-up objective assessment. Nonadherence in 1 medication might also indicate nonadherence in other medications. Clinical implications and future research directions are provided.