Morphine Use in Acute Heart Failure and Limitation of Therapeutic Effort

Abstract

Miró et al1Miró Ò. Gil V. Martín-Sánchez F.J. Herrero-Puente P. et al.ICA-SEMES Research GroupMorphine use in the ED and outcomes of patients with acute heart failure: a propensity score-matching analysis based on the EAHFE Registry.Chest. 2017; 152: 821-883Abstract Full Text Full Text PDF PubMed Scopus (45) Google Scholar should be congratulated for their multicenter study published in CHEST (October 2017) analyzing the impact of morphine use on mortality of patients admitted with acute heart failure in the ED. The interesting approach by means of propensity score matching techniques allowed investigators to adjust the analysis when confounding variables were not balanced. The main risk of bias of these techniques seems to be if the propensity score model does not include a variable strongly associated with outcome and classification variable.2Adelson J.L. McCoach D.B. Rogers H.J. Adelson J.A. Sauer T.M. Developing and applying the propensity score to make causal inferences: variable selection and stratification.Front Psychol. 2017; 8: 1413Crossref PubMed Scopus (21) Google Scholar In the study by Miró et al,1Miró Ò. Gil V. Martín-Sánchez F.J. Herrero-Puente P. et al.ICA-SEMES Research GroupMorphine use in the ED and outcomes of patients with acute heart failure: a propensity score-matching analysis based on the EAHFE Registry.Chest. 2017; 152: 821-883Abstract Full Text Full Text PDF PubMed Scopus (45) Google Scholar knowing the age and comorbidity of patients included in the register, the prompt decision of limitation of the therapeutic effort, which is both related to mortality and morphine administration, has not been included as a confounding variable. The main difference observed in mortality in the study occurs in the ED and after discharge from emergency setting, and it could be related to decisions of limitation of the therapeutic effort. In a previous study with the Epidemiology of Acute Heart Failure in Emergency Department multicenter database,3Jacob J. Miró Ò. Herrero P. et al.en representación del grupo ICA-SEMESPredicting short- term mortality in patients with acute exacerbation of chronic heart failure: the EAHFE-3D scale.Med Intensiva. 2016; 40: 348-355Crossref PubMed Scopus (20) Google Scholar a predictive model of short-term mortality was developed in patients with acute heart failure, and morphine and limitation of the therapeutic effort were not considered. Moreover, another recent study using Cox regression by Dominguez-Rodriguez et al4Dominguez-Rodriguez A. Avanzas P. Burillo-Putze G. Abreu-Gonzalez P. Influence of morphine treatment on in-hospital mortality among patients with acute heart failure.Med Intensiva. 2017; 41: 382-384Crossref PubMed Scopus (12) Google Scholar was conducted in 991 patients treated for heart failure in the ED. The study showed that morphine was associated with in-hospital mortality, but decisions of limitation were also not considered. The results of these studies can help to modify the management of acute heart failure, but it is necessary to construct well-designed clinical trials with a clear definition of use for morphine. Morphine Use in the ED and Outcomes of Patients With Acute Heart Failure: A Propensity Score-Matching Analysis Based on the EAHFE RegistryCHESTVol. 152Issue 4PreviewThe objective was to determine the relationship between short-term mortality and intravenous morphine use in ED patients who received a diagnosis of acute heart failure (AHF). Full-Text PDF ResponseCHESTVol. 153Issue 3PreviewGarcía Garmendia et al are absolutely right in underlining that propensity score methodology can lead to misleading conclusions if unrecorded confounding variables are not balanced among groups. This risk, present in all multivariate adjustment methods, can only be avoided by randomized clinical trials. This limitation applies for our paper recently published in CHEST in which we reported that the use of IV morphine in acute heart failure (AHF) could be associated with an increased 30-day mortality. Full-Text PDF