Overweight followed by obesity have the lowest mortality among patients with systolic or diastolic heart failure independent of comorbidities whereas cachexia has the highest mortality.

IntroductionA phenomenon known as the obesity paradox has been reported in patients with heart failure (HF) suggesting lower mortality with increasing weight. The goal of this study is to characterize this observation in HF using the largest available inpatient database of adult patients. MethodWe searched the National Inpatient Sample (NIS) database for patients for the years 2016-2020 with a diagnosis of systolic (SHF) or diastolic heart failure (DHF) using International Classification of Diseases, Tenth Revision (ICD-10) diagnosis codes. We evaluated mortality association based on body weight. Multivariate statistical analysis was performed to adjust all-cause inpatient mortality for comorbidities. ResultsThere was a total of 7,364,023 patients with a diagnosis of SHF and 10,064,223 patients with a diagnosis of DHF. All-cause inpatient mortality was lowest in overweight patients followed by those with obesity and morbid obesity, whereas mortality was highest in cachexia compared to normal weight for SHF and DHF patients (mortality: overweight 2.56%, obese 3.12%, morbidly obese 3.70%, normal weight 5.60%, and cachexia 15.22%; p<0.001) and DHF patients (mortality: overweight 2.08%, obese 2.43%, morbidly obese 2.93%, normal weight 4.58%, and cachexia 14.25%; p<0.001). This relationship remains similar after multivariate analysis. (SHF patients: overweight OR: 0.49 (0.41-0.58), obesity OR: 0.64 (0.62-0.66), morbid obesity OR: 0.85 (0.83-0.88), and cachexia OR: 2.78 (2.67-2.90); p<0.001; DHF patients: overweight OR: 0.47 (0.40-0.56), obesity OR: 0.61 (0.59-0.63), morbid obesity OR: 0.83 (0.81-0.85), and cachexia OR: 3.09 (2.96-3.23); p<0.001). ConclusionOur data observed that all-cause inpatient mortality in SHF and DHF is lowest in overweight populations followed by obese and morbidly obese populations whereas cachexia has the highest mortality. However, increasing weight above the overweight reduces the obesity paradox benefit.