Let's talk about medication: concordance in rating medication adherence among multimorbid patients and their general practitioners

Background: Medication adherence can be essential for improving health outcomes. Patients with multiple chronic conditions, often receiving multiple medications, are at higher risk for medication nonadherence. Previous research has focused on concordance between patients and providers about which medication should be taken. However, the question of whether patients and providers are concordant in rating actual medication intake has not been answered as yet. This study aimed to explore the extent and predictors of patient - provider concordance in rating medication adherence in patients with multiple chronic conditions.

Methods: Overall medication adherence was measured by self-report (Medication Adherence Report Scale, MARS-D) in a sample of 92 patients with multiple chronic conditions. Twelve treating primary care physicians were asked to rate medication adherence in these patients using a mirrored version of the MARS-D. Concordance between external rating and self-reported medication adherence was analyzed descriptively. Predictors of concordance in rating medication adherence were explored in a multilevel analysis.

Results: Patients rate their medication adherence markedly higher than their general practitioner. Accordingly, the percentage of concordance ranges between 40% (forgot to take medication) and 61% (deliberately omitted a dose). In multilevel analysis, concordance in rating medication adherence was positively associated with being the single primary care provider (β 2.24, P < 0.0001) and frequent questioning about medication use (β 0.66, P = 0.0031). At the patient level, "not [being] married" (β -0.81, P = 0.0064) and "number of prescribed medications" (β -0.10, P = 0.0203) were negative predictors of patient - provider concordance in rating medication adherence.

Conclusion: Concordance for rating medication adherence between general practitioners and their patients was low. Talking about medication on a regular basis and better continuity of care may enhance patient - provider concordance in rating medication adherence as a prerequisite for shared decisions concerning medication in patients with multiple chronic conditions.