Pharmaceutical outcomes research to better understand medication non-adherence in patients with Systemic Lupus Erythematosus

Introduction: This thesis comprises a systematic review and a pharmacoepidemiological study aimed at improving the understanding about medication non-adherence to antimalarials (AM) in Systematic Lupus Erythematosus (SLE). AM is the conventional and effective long-term treatment option that has resulted in substantial decreases in deaths associated with SLE disease activity. However, there seems to be no such decline in the deaths associated with the sequelae of SLE (such as circulatory disease). Since deriving therapeutic effects from AM depends not only on physicians prescribing the appropriate treatment, but also on patients’ adherence with selected treatment, there is the need for a better understanding of medication non-adherence to AM in SLE. Objective: 1) To systematically review and synthesize the literature on medication adherence in SLE to identify key gaps in the literature; and 2) to evaluate the burden and determinants of medication non-adherence to AM in SLE. Methods: To address Objective 1, I have conducted a systematic review. I conducted a mapped search of Medline, Embase, and Web of Science to identify original, observational studies that indicated the data source and measurement tool to assess medication adherence in a SLE patient sample. To address Objective 2, I have conducted a longitudinal pharmacoepidemiological study of a population-based SLE cohort. I used a Cox’s proportional hazard ratio model to examine factors that were significantly associated with discontinuation of AM. Results: 1) 11 studies were included in the systematic review, and the majority of these studies reported that less than 50% of SLE patients are sufficiently adherent to their medications; 2) After five years, only 33% of patients remained on AM therapy; and 3) Higher SES and the following time-varying covariates updated monthly: glucocorticoids use, traditional NSAIDs use, rate of rheumatologist visits, and rate of dermatologists were statistically significantly protective against discontinuation of AM therapy. Conclusion: Altogether as a collective work, this thesis provides evidence that demonstrates medication non-adherence is a substantial problem in SLE. In addition, it highlights the importance of developing adherence interventions to help support patients taking their medications as prescribed.Pharmaceutical Sciences, Faculty ofGraduat