Abstract 13180: Poor Adherence to Medication is an Independent Risk Factor for Adverse Clinical Outcomes in Heart Failure with Reduced Ejection Fraction (HFrEF) but not Heart Failure with Preserved Ejection Fraction (HFpEF)
Purpose: One of the most important self-care behaviors is taking the medication in patients with heart failure (HF). The purpose of this study was to clarify the relationship of medication adherence with clinical outcomes, and to identify factors related to the adherence in HF with reduced left ventricular ejection fraction (HFrEF, LVEF < 50%) and preserved LVEF (HFpEF, LVEF ≥ 50%).
Methods: A total of 275 outpatients in two independent hospitals completed the self-administered questionnaire. Patients were asked about their medication adherence “I take my medication as prescribed” on a 5-point scale from 1 (I completely agree) to 5 (I do not agree at all). We defined poor adherence as the score of 2 or greater.
Results: Of 275 patients, 135 (49 %) had HFrEF. Most patients were male (80 % in HFrEF, 59 % in HFpEF). Mean age in HFrEF was similar to that in HFpEF (62.9±13.5 vs. 65.7±13.6 years). HFrEF patients were treated more frequently with beta-blockers and angiotensin converting enzyme inhibitors/angiotensin receptor blockers compared with HFpEF patients (83% vs. 55%, 74% vs. 54%, respectively, both P < 0.001). The prevalence of poor adherence to medication did not significantly differ between HFrEF and HFpEF patients (7.4 % vs. 6.4%, P = 0.749). During the median of 1.1-year follow-up, HFrEF patients with poor adherence had more cardiac death or HF hospitalization than those with good adherence (50 % vs. 36 %, P = 0.033). Multivariate Cox regression analysis adjusted by age and B-type natriuretic peptide (BNP) levels showed that poor adherence to medication was still associated with 4.5-fold increased risk of the adverse events in HFrEF (hazard ratio 4.54, 95% confidence interval 1.51-13.69, P < 0.001). In contrast, no significant difference in the adverse events was shown between HFpEF patients with and without poor medication adherence (P = 0.148). In the logistic regression analysis, demographic and clinical factors including age, gender, married status, and levels of BNP were not associated with the medication adherence in HFrEF as well as HFpEF.
Conclusions: Poor adherence to medication is an independent risk factor in HFrEF but not in HFpEF, which may be reflected that any of available pharmacological therapy is not established to improve clinical outcomes of HFpEF.
- © 2012 by American Heart Association, Inc.