Difficulty taking medications, depression, and health status in heart failure patients.

BACKGROUND: Little is known about medication nonadherence in heart failure populations. We evaluated the association between 1 aspect of medication nonadherence, patient-reported difficulty taking medications as directed, and health status among heart failure outpatients, and then examined whether this association was explained by depression. METHODS AND
RESULTS: A total of 522 outpatients with left ventricular ejection fraction <0.40 completed clinical evaluation, Kansas City Cardiomyopathy Questionnaire (KCCQ), Medical Outcomes Study-Depression questionnaire, and categorized their difficulty taking medications (5-level Likert-scale question). Multivariable regression was used to evaluate the cross-sectional association between difficulty taking medications and health status, with incremental adjustment for medical history and depressive symptoms. Patients with difficulty taking medications (n = 64; 12.2%) had worse health status (8.2 +/- 2.7 point lower mean KCCQ summary scores; P = .008) and more depressive symptoms (43.8% versus 27.1%; P = .006). Adjusting for demographic and clinical factors had little effect on the association between difficulty taking medications and health status (8.0 +/- 3.2 point lower KCCQ scores; P = .01); however, the relationship was attenuated with adjustment for depressive symptoms (4.7 +/- 2.9 point lower KCCQ scores; P = .11).
CONCLUSIONS: Among heart failure outpatients, difficulty taking medications is associated with worse health status. This association appears to be explained, in part, by coexistent depression. Future studies should evaluate interventions such as depression treatment to improve medication adherence and health status.