McKay, Kyla A.Tremlett, HelenPatten, Scott B.Fisk, John D.Evans, CharityFiest, KirstenCampbell, TrudyMarrie, Ruth Ann2019-01-242019-01-242017McKay, K. A., Tremlett, H., Patten, S. B., Fisk, J. D., Evans, C., … Fiest, K. (2016). Determinants of non-adherence to disease-modifying therapies in multiple sclerosis: A cross-Canada prospective study. Multiple Sclerosis Journal, 23(4), 588–596. https://doi.org/10.1177/13524585166574401352-4585http://hdl.handle.net/1880/109521The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: The study was funded by the Canadian Institutes of Health Research (CIHR CBG 101829), the Rx&D Health Research Foundation and by a Don Paty Career Development Award from the MS Society of Canada (to RAM).Background: Poor adherence to the disease-modifying therapies (DMTs) for multiple sclerosis (MS) may attenuate clinical benefit. A better understanding of characteristics associated with non-adherence could improve outcomes. Objective: To evaluate characteristics associated with non-adherence to injectable DMTs. Methods: Consecutive patients from four Canadian MS Clinics were assessed at three time points over two years. Clinical and demographic information included self-reported DMT use, missed doses in the previous 30 days, health behaviors, and comorbidities. Non-adherence was defined as <80% of expected doses taken. We employed generalized estimating equations to examine characteristics associated with non-adherence at all time points with findings reported as adjusted odds ratios (OR). Results: In all, 485 participants reported use of an injectable DMT, of whom 107 (22.1%) were non-adherent over the study period. Non-adherence was associated with a lower Expanded Disability Status Scale score (0-2.5 vs 3.0-5.5, OR: 1.80; 95% confidence interval (CI): 1.06-3.04), disease duration (>= 5 vs < 5 years, OR: 2.23; 95% CI: 1.10-4.52), alcohol dependence (OR: 2.14; 95% CI: 1.23-3.75), and self-reported cognitive difficulties, measured by the Health Utilities Index-3 (OR: 1.55; 95% CI: 1.08-2.22). Conclusions: Nearly one-quarter of participants were non-adherent during the study. Alcohol dependence, perceived cognitive difficulties, longer disease duration, and mild disability status were associated with non-adherence. These characteristics may help healthcare professionals identify patients at greatest risk of poor adherence.http://creativecommons.org/licenses/by/3.0/Multiple sclerosisadherenceimmunomodulatory therapyglatiramer acetatebeta-interferonhealth behaviorArticleCBG 10182910.1177/135245851665744010.11575/PRISM/35780