AUTHOR=Elbaz-Greener Gabby , Rozen Guy , Carasso Shemy , Yarkoni Merav , Wijeysundera Harindra C. , Alcalai Ronny , Gotsman Israel , Rahamim Eldad , Planer David , Amir Offer 

TITLE=The Relationship Between Body Mass Index and In-hospital Survival in Patients Admitted With Acute Heart Failure

JOURNAL=Frontiers in Cardiovascular Medicine

VOLUME=Volume 9 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/cardiovascular-medicine/articles/10.3389/fcvm.2022.855525

DOI=10.3389/fcvm.2022.855525

ISSN=2297-055X

ABSTRACT=Background: The association between Body Mass Index (BMI) and clinical outcomes following acute heart failure (AHF) hospitalization is debated in the literature. Our objective was to study the real-world relationship between BMI and in-hospital mortality in patients who were admitted with AHF.
Methods: In this retrospective, multi-center study, we utilized the National Inpatient Sample (NIS) database to identify a sampled cohort of patients who were hospitalized with AHF between October 2015 and December 2016.   Outcomes of interest included in-hospital mortality and length of stay. Patients were divided into 6 BMI (kg/m2) subgroups according to the World Health Organization (WHO) classification: (1) under-weight ≤19, (2) normal-weight 20-25, (3) over-weight 26-30, (4) obese I 31-35, (5) obese II 36-39, and (6) extremely obese ≥40.  A multivariable logistic regression model was used to identify predictors of in-hospital mortality and to identify predictors of length of stay (LOS).
Results: Among a weighted total of 219,950 hospitalizations for AHF across the U.S. who were analyzed. The mean age was 66.3+31.5 years; most patients (51.8%) were male.   The crude data showed a non-linear complex relationship between BMI and AHF population outcomes. Patients with elevated BMI exhibited significantly lower in-hospital mortality compared to the under-weight and normal-weight study participants (5.5%, 5,5%, 2,8%, 1.6%, 1.4%, 1.6% in groups by BMI ≤19, 20-25, 26-30, 31-35, 36-39 and, ≥40 respectively, p<0.001) as well as shorter LOS.  In the multivariable regression model, BMI subgroups of ≤25kg/m2 were found to be independent predictors of in-hospital mortality. Age and several comorbidities, as well as the Deyo Comorbidity Index, were found to be independent predictors of increased mortality in the study population
Conclusions: A reverse J-shaped relationship between BMI and mortality was documented in patients hospitalized for AHF in the recent years confirming the "obesity paradox" in the real-world setting.