[en] INTRODUCTION: Spironolactone and eplerenone are both recommended for the treatment of heart failure and reduced ejection fraction (HFrEF) according to practice guidelines, as both drugs demonstrated consistent reductions of mortality and morbidity in these patients. However, given the absence of direct comparative studies, it is not known whether any differences regarding their prognostic benefit can exist between them. OBJECTIVES: We aimed to evaluate the effectiveness of spironolactone and eplerenone in patients with HFrEF in a real-world clinical setting. METHODS: Using Fine-Gray´s competing risk regression, we compared the clinical outcomes of 293 patients with chronic heart failure (HF) and left ventricular ejection fraction <40% treated with eplerenone and 293 propensity-score matched individuals treated with spironolactone. Study subjects were selected from a prospective cohort of 1404 ambulatory patients with HFrEF seen since 2010 to 2019 in a single specialized HF clinic, among which 992 received a mineralocorticoid receptor antagonist at baseline. Median follow-up was 3.95 years. RESULTS: No statistically significant differences between patients treated with eplerenone versus spironolactone were observed with regard to the risk of the primary composite end-point cardiovascular death or HF hospitalization [hazard ratio (HR) 0.95; 95% confidence interval (95% CI) 0.73-1.23; p=0.677]. However, eplerenone use was associated to lower cardiovascular mortality (HR 0.55; 95% CI 0.35-0.85; p=0.008) and lower all-cause mortality (HR 0.67; 95% CI 0.47-0.95; p=0.027). The incidence of drug suspension due to side effects (HR 0.58; 95% CI 0.40-0.85; p=0.005) and drug suspension due to any reason (HR 0.70; 95% CI 0.51-0.97; p=0.033) were lower among patients treated with eplerenone. CONCLUSIONS: In this observational, real-world, propensity-score matched study of patients with HFrEF, no statistically significant differences between patients treated with eplerenone versus spironolactone were observed with regard to the risk of the primary composite end-point cardiovascular death or HF hospitalization. However, eplerenone was associated to lower cardiovascular mortality and lower all-cause mortality than spironolactone.

[gl] INTRODUCIÓN: Espironolactona e eplerenona presentan, segundo as guías de práctica clínica, un mesmo grao de recomendación para o tratamento da insuficiencia cardíaca con fracción de exección reducida (IC-FEr) sintomática, xa que os dous fármacos teñen demostrado de forma consistente unha redución da morbimortalidade destes pacientes. Non obstante, dada a ausencia de estudos comparativos directos, descoñécese se poden existir diferenzas entre eles en canto ó seu beneficio prognóstico. OBXECTIVOS: O obxectivo deste estudo foi avaliar a efectividade de espironolactona e eplerenona en pacientes con IC-FEr nun escenario clínico de vida real. MÉTODOS: Utilizando a regresión de Fine-Gray para riscos competitivos, comparamos os eventos clínicos de 293 pacientes con insuficiencia cardíaca (IC) crónica e fracción de exección <40% tratados con eplerenona con 293 individuos tratados con espironolactona emparellados por puntuación de propensión. Os pacientes do estudo foron seleccionados dunha cohorte prospectiva de 1404 pacientes ambulatorios con IC-FEr valorados dende 2010 ata 2019 nunha única unidade especializada de IC, dos cales 992 recibiron tratamento cun antagonista do receptor mineralocorticoide basalmente. A mediana de seguimento foi de 3,95 anos. RESULTADOS: Non se observaron diferenzas significativas entre pacientes tratados con eplerenona versus espironolactona no tocante ó obxectivo primario combinado de morte cardiovascular ou hospitalización por IC [hazard ratio (HR) 0,95; intervalo de confianza ó 95% (IC 95%) 0,73-1,23; p=0,677]. Non obstante, o uso de eplerenona asociouse a unha menor mortalidade cardiovascular (HR 0,55; IC 95% 0,35-0,85; p=0,008) e a unha menor mortalidade por todas as causas (HR 0,67; IC 95% 0,47-0,95; p=0,027). A incidencia de suspensión do fármaco debido a efectos adversos (HR 0,58; IC 95% 0,40-0,85; p=0,005) e debido a calquera causa (HR 0,70; IC 95% 0,51-0,97; p=0,033) foi menor nos pacientes a tratamento con eplerenona. CONCLUSIÓNS: Neste estudo observacional en vida real de pacientes con IC-FEr, con emparellamento por puntuación de propensión, non observamos unha diferenza significativa entre o tratamento con eplerenona ou espironolactona en canto á incidencia acumulada do evento combinado mortalidade cardiovascular ou ingreso por IC. Non obstante, a eplerenona asociouse a unha menor mortalidade cardiovascular e a unha menor mortalidade por todas as causas en comparación con espironolactona.