Impact of adherence to guideline-directed therapy on risk of death in HF patients across an ejection fraction spectrum

Aims How different degrees of adherence to guideline-directed medical therapy (GDMT) affect mortality risk in patients with heart failure (HF) in a real-world clinical setting is poorly understood. This study sought to investigate how different levels of adherence to GDMT were associated with the risk of all-cause mortality in patients with HF across a spectrum of left ventricular ejection fractions (LVEFs) in a real-world clinical setting.Methods and results A total of 64 610 HF patients with no missing value of LVEF from the Swedish Heart Failure Registry were included in the study. Patients were divided according to different LVEFs (<30%, 30-39%, 40-49%, and >= 50%) and stratified by an adherence score (good, moderate, or poor) according to the triple, double, and single one usage of GDMT: angiotensin-converting enzyme inhibitors/angiotensin receptor blockers, beta-blockers, and mineralocorticoid receptor antagonists. The outcome is time to all-cause mortality. The mean age of the whole cohort was 73.9 +/- 12.1 years, and the proportion of patients in LVEF < 30%, 30-39%, 40-49%, and >= 50% groups was 27.6%, 26.9%, 22.1%, and 23.3%, respectively. Patients with LVEF < 30% had the highest mortality rate, almost 20% higher than those with LVEF >= 50% {hazard ratio [HR] [95% confidence interval (CI)]: 0.80 [0.71-0.90], P < 0.001}. After treatment of GDMT with good adherence, patients with LVEF < 30% had similar mortality to those with LVEF >= 50% [HR (95% CI): 0.97 (0.86-1.10), P = 0.664]. However, the percentage of moderate or poor GDMT was alarmingly high, with good adherence only in 20% of the patients.Conclusions Good adherence to GDMT works best in patients with LVEF < 50%, whereas moderate adherence to GDMT varies in efficacy depending on the components of the drug combinations.