Nonadherence with immunosuppressive drugs: US compared with European kidney transplant recipients

Background—System factors increasingly are suggested as important yet understudied correlates of nonadherence.Objective—To explore the relationship between healthcare system and prevalence of nonadherence with immunosuppressive regimen by studying variation in non-adherence between European and US kidney transplant recipients and as well as nonadherence in European countries.Methods—We performed a secondary data analysis on data collected in 3 independent cross-sectional studies using comparable methodology including patients from the United States, the Netherlands, Belgium, and Switzerland. Nonadherence was measured using 1 item of the Siegal questionnaire. Patients were categorized as nonadherent if they reported missing a dose of immunosuppression in the last 4 weeks. Analyses were performed by multiple mixed logistic regression, with center as a random effect and clinical and demographical differences between groups as fixed effects.Results—1563 US and 614 European patients from 3 different countries ...