Association of medication adherence, knowledge, and skills with emergency department visits by adults 50 years or older with congestive heart failure

Purpose. The association of medication adherence, knowledge, and skills with emergency department (ED) visits by patients 50 years of age or older with congestive heart failure (CHF) was studied. Methods. The patients in this study were enrolled in the usual care group of an ongoing trial of patients with CHF to determine the effects of a pharmacy-based intervention on relevant outcomes. Participants' medication knowledge and skills were assessed during individual interviews. Medication knowledge assessed patients' knowledge of the dosage, frequency, and indication of each of their CHF medications. The medications skills assessment evaluated patients' dexterity (ability to open medication bottles), literacy (ability to read labels), and ability to distinguish colors of tablets and capsules. Medication adherence to CHF drugs was calculated from electronic monitors and prescription-refill records over a six-month period. The primary outcomes of this study were the numbers of all-cause cardiovascular and CHF-specific ED visits during a six-month period. Log-linear regression models were used to analyze the effects of medication knowledge, skill, and adherence on ED visits. Results. Sixty-one patients participated in this study. Multivariate log-linear models adjusted for demographic variables showed that lower medication adherence (p < 0.001) and an inability to read standard prescription and auxiliary labels (p = 0.002) were associated with an increased number of cardiovascular-related ED visits. Knowledge of the prescribed dose was associated with CHF-specific ED visits (p < 0.001). Conclusion. Greater medication knowledge, skills, and adherence were associated with fewer ED visits among patients 50 years of age or older with CHF in an urban, teaching medical center.