Risk Factors for Suboptimal Medication Adherence in Persons With Multiple Sclerosis: Development of an Electronic Health Record-Based Explanatory Model for Disease-Modifying Therapy Use

Abstract

ObjectiveTo determine which factors are associated with suboptimal disease-modifying therapy (DMT) adherence and to develop an explanatory model that could be used to identify individuals at risk and potentially inform interventions. DesignCross-sectional cohort study using electronic health records. SettingVeterans Health Administration (VA). ParticipantsVeterans with multiple sclerosis (MS) (N=2939; 79.69% men) who received care through the VA and were included in the VA MS Center of Excellence Data Repository. InterventionsNot applicable. Main Outcome MeasuresSuboptimal DMT adherence (<80%), demographics, co-occurring conditions, and health care use. ResultsNearly 31% of participants had suboptimal adherence. Flags for suboptimal adherence included >20% missed appointments (odds ratio [OR], 3.78; 95% CI, 2.45-2.82), traumatic brain injuries (OR, 1.55; 95% CI, 1.12-2.14), age younger than 59 years (OR, 1.47; 95% CI, 1.23-1.74), ≥1 emergency department visits (OR, 1.40; 95% CI, 1.18-1.67), mood disorders (ie, depressive and bipolar disorders) (OR, 1.40; 95% CI, 1.18-1.66), and service connection (OR, 1.22; 95% CI, 1.01-1.47). Hyperlipidemia (OR, 0.77; 95% CI, 0.65-0.92) and being issued a wheelchair (OR, 0.83; 95% CI, 0.70-1.00) were associated with lower risk. ConclusionsSuboptimal adherence to DMTs continues to be an issue. Interventions that focus on person-level barriers should be urgently explored to increase adherence and improve self-management abilities.