Nonadherence Prevalence Research Articles

The spectrum of nonadherence with medication in heart, liver, and lung tranplant patients assessed in various ways

Adherence to medication regimes is crucial for transplant patients. Addressing methodological limitations and gaps in the literature, we studied: (i) the prevalence of nonadherence (NA) with immunosuppression (IS) using various measurement methods, (ii) NA prevalence regarding intake and timing, (iii) changes in NA over time, (iv) differences in NA across organ transplant populations, (v) NA regarding co-medication. Using a descriptive, prospective, comparative design over 3 months, we included convenience samples of adult heart (n=79), liver (n=55), and lung (n=104) transplant patients. NA with IS was measured using self-report, collateral report, blood assay, electronic monitoring (Helping Hand™ , Bang and Olufsen Medicom, Denmark), and their combinations. In the overall sample, depending on the method used, IS NA ranged from 23.9% to 70.0%. For co-medication, the overall NA rate was 30.1% using self-report. Nonadherence rates remained stable over time. At inclusion, significant NA differences between organ groups were reported via self- and collateral report; lung transplant patients were less adherent than heart or liver transplant recipients, both to IS and to co-medication.

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

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.

Diagnostic Accuracy of Measurement Methods to Assess Non-Adherence to Immunosuppressive Drugs in Kidney Transplant Recipients

Valid assessment of immunosuppressive therapy non-adherence (NAH) is vital: NAH is associated with negative transplantation outcomes. We studied the diagnostic accuracy of assay, patient self-reports and clinicians' collateral reports and composite adherence scores using electronic monitoring (EM) as a reference standard. This cross-sectional study included a convenience sample of 249 adult kidney transplant recipients (Ktx) (female: 43.4%; mean age 53.6 [SD: 12.7], median 7 years [IQR: 9 years] post-Ktx). NAH was assessed using EM over 3 months (i.e. reference standard), assays of cyclosporine, tacrolimus, mycophenolat-mofetil, patients' self-reports and clinicians' collateral reports. The constructed composite adherence score included assay, self-reports and collateral reports. NAH's prevalence across the measurement methods was EM: 17.3%; assay: 33% (cyclosporine: 25.8%; tacrolimus: 35.1%; mycophenolat-mofetil: 40.2%); self-report: 12.4%; collateral reports: 24.9% and composite adherence score: 38.9%, respectively. The composite adherence score and collateral reports showed the highest and lowest sensitivities to NAH (72.1% and 15.8%, respectively). Specificity was highest for collateral reports of at least three clinicians (93.1%). Likelihood ratio of a positive test was 2.74 for composite adherence score. No measures showed high sensitivity alongside high specificity. Combining measures increased diagnostic accuracy, indicating the relevance of combined measures for clinical and research purposes.