Demographic, Socioeconomic, and Psychological Factors Related to Medication Non-adherence Among Emergency Department Patients

Background: Many Emergency Department (ED) visits are related to medication non-adherence; however, the contributing factors are poorly understood. Objectives: To explore the relative contributions of demographic, socioeconomic, and psychological factors to medication non-adherence in an ED population. Methods: This was a cross-sectional analysis enrolling patients with one of three illnesses requiring chronic medication usage (hypertension, diabetes, or seizures). Trained research associates administered a 60-item survey that assessed demographic and socioeconomic information, as well as a variety of psychological factors potentially relevant to adherence (health attitudes, health beliefs, depression, anxiety, social support, and locus of control). Patients rated their overall prescription medication adherence and estimated the number of days in the preceding month on which doses were missed. In addition, treating physicians estimated the degree to which the ED visit was related to medication non-adherence; clinical data were abstracted to help validate patient and physician assessments. The relationships between non-adherence and demographic, socioeconomic, and psychological variables were explored using multivariate statistics and logistic regression. Covariance analysis was performed to validate subscales, and receiver-operator curves were used to define optimal threshold values. Results: A total of 472 patients consented to participate, with good representation for various demographic and socioeconomic groups. Each psychological factor related significantly to both patient and physician ratings of non-adherence (p < 0.05). Of all demographic and socioeconomic factors examined, only current or historical drug use predicted non-adherence. Conclusions: Psychological factors seem to be important determinants of medication non-adherence among ED patients. These data may help define future research directions and interventions.