The mediating role of trust in physicians on the association between multidimensional health literacy and medication adherence in hemodialysis: A cross-sectional study

Abstract

AbstractRationale & ObjectiveBasic health literacy (HL) and trust in physicians can influence medication adherence (MA) in dialysis patients. However, how high-order HL is associated with MA, and how trust in physicians mediates this association remain unclear. We assessed the interrelationships between HL, trust in physicians, and MA, and investigated the mediating role of trust in physicians in the relationship between HL and MA.Study DesignMulticenter cross-sectional study.Setting & ParticipantsJapanese adults receiving outpatient hemodialysis at six dialysis centers.ExposuresMultidimensional HL was measured using the 14-item Functional, Communicative, and Critical Health Literacy Scale. Trust in physicians was measured using the five-item Wake Forest Physician Trust Scale.OutcomeMA was measured using the 12-item Adherence Starts Knowledge (ASK-12) scale.Analytical ApproachA series of general linear models was created to analyze the associations between HL and ASK-12 scores with and without trust in physicians. Mediation analysis was performed to determine whether trust in physicians mediated this association.ResultsIn total, 455 patients were analyzed. Higher functional and communicative HL were associated with lower barriers to MA (per 1-point increase: -1.90 (95% confidence interval (CI): -2.67, -1.13) and -2.11 (95% CI: -3.35, -0.87), respectively), whereas higher critical HL was associated with higher barriers (per 1-point increase: 1.67 (95% CI: 0.43, 2.90)). After controlling for trust in physicians, the magnitude of the association between HLs and MA decreased. Trust in physicians partially mediated the association between functional or communicative HL and MA (especially “beliefs”) and completely mediated the association between critical HL and MA (especially “behaviors”).LimitationPossible reverse causation.ConclusionsIn addition to functional HL, communicative and critical HL were associated with MA, and their associations were mediated by trust in physicians. To effectively improve MA, individualized strategies for each HL and favorable physician–patient interactions are important.