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

Center for the Promotion of Treatment Adherence and Self-Management, Cincinnati, Ohio 45229-3039, USA.
Inflammatory Bowel Diseases (Impact Factor: 4.46). 04/2009; 15(4):589-93. DOI: 10.1002/ibd.20798
Source: PubMed


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

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Available from: Kevin Hommel, Mar 12, 2014
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    • "Although our sample was relatively homogeneous, it is demographically similar to samples previously reported in pediatric IBD studies (Mackner & Crandall, 2007). Self-report, the most commonly used method to measure adherence, has a tendency to overestimate adherence compared to more objective measures such as pill counts, electronic monitoring, or blood assays (Hommel et al., 2009; La Greca, 1995). However, this approach was used for two reasons. "
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    ABSTRACT: Knowledge of factors impacting adolescents' ability to adhere to their inflammatory bowel disease (IBD) regimen is limited. The current study examines the collective impact of barriers to adherence and anxiety/depressive symptoms on adolescent adherence to the IBD regimen. Adolescents (n = 79) completed measures of barriers to adherence, adherence, and anxiety/depressive symptoms at one of two specialty pediatric IBD clinics. Most adolescents reported barriers to adherence and 1 in 8 reported borderline or clinically elevated levels of anxiety/depressive symptoms. Anxiety/depressive symptoms moderated the relationship between barriers to adherence and adherence. Post hoc probing revealed a significant, additive effect of higher anxiety/depressive symptoms in the barriers-adherence relationship, with adherence significantly lower among adolescents with higher barriers and higher anxiety/depressive symptoms. In order to optimize adherence in adolescents, interventions should target not only barriers to adherence but also any anxiety/depressive symptoms that may negatively impact efforts to adhere to recommended treatment.
    Journal of Pediatric Psychology 11/2011; 37(3):282-91. DOI:10.1093/jpepsy/jsr092 · 2.91 Impact Factor
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    • "Moreover, there is evidence that increased number of barriers is related to poorer adherence (Logan et al., 2003; Riekert & Drotar, 2002). A recent study in IBD reported that forgetting, being away from home, and interference with activities were the most common barriers to adherence, and that greater number of barriers were correlated with poorer self-reported adherence (Ingerski, Baldassano, Denson, & Hommel, 2009). However, this study relied exclusively on forced-choice quantitative data, and the self-reported adherence estimates were likely overestimated by participants (Ingerski et al., 2009). "
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    ABSTRACT: To examine perceived barriers to medication adherence in inflammatory bowel disease (IBD) treatment and their relationship with adherence using a combined forced choice and semi-structured interview assessment approach. Sixteen adolescents with IBD and their parents participated in an open-ended interview regarding adherence barriers and completed quantitative measures of adherence, barriers to treatment, and disease severity. The most commonly identified barriers to adherence were forgetting, interference with other activities, difficulty swallowing pills, and not being at home. Number of reported barriers was positively correlated with objective nonadherence for 6-MP/azathioprine. Nonadherence frequency was 42% for 6-MP/azathoprine and 50% for 5-ASA medications. Using a combined assessment approach, patients and parents reported several barriers to treatment adherence that are appropriate for clinical intervention. This is critical given the significant medication nonadherence observed in this sample and the relationship between total number of barriers and disease management problems.
    Journal of Pediatric Psychology 12/2009; 35(9):1005-10. DOI:10.1093/jpepsy/jsp126 · 2.91 Impact Factor
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