Obesity Paradox and Functional Outcomes in Sepsis: A Multicenter Prospective Study

Abstract

OBJECTIVES: In Asian populations, the correlation between sepsis outcomes and body mass is unclear. A multicenter, prospective, observational study conducted between September 2019 and December 2020 evaluated obesity’s effects on sepsis outcomes in a national cohort. SETTING: Nineteen tertiary referral hospitals or university-affiliated hospitals in South Korea. PATIENTS: Adult patients with sepsis (n = 6,424) were classified into obese (n = 1,335) and nonobese groups (n = 5,089). MEASUREMENTS AND RESULTS: Obese and nonobese patients were propensity score-matched in a ratio of 1:1. Inhospital mortality was the primary outcome. After propensity score matching, the nonobese group had higher hospital mortality than the obese group (25.3% vs 36.7%; p < 0.001). The obese group had a higher home discharge rate (70.3% vs 65.2%; p < 0.001) and lower median Clinical Frailty Scale (CFS) (4 vs 5; p = 0.007) at discharge than the nonobese group, whereas the proportion of frail patients at discharge (CFS ≥ 5) was significantly higher in the nonobese group (48.7% vs 54.7%; p = 0.011). Patients were divided into four groups according to the World Health Organization body mass index (BMI) classification and performed additional analyses. The adjusted odds ratio of hospital mortality and frailty at discharge for underweight, overweight, and obese patients relative to normal BMI was 1.25 (p = 0.004), 0.58 (p < 0.001), and 0.70 (p = 0.047) and 1.53 (p < 0.001), 0.80 (p = 0.095), and 0.60 (p = 0.022), respectively. CONCLUSIONS: Obesity is associated with higher hospital survival and functional outcomes at discharge in Asian patients with sepsis.

Obesity Paradox in Sepsis: Role of Adipose Tissue in Storing Mitochondrial Toxins

“…Our previous work has also shown that an obesity paradox exists in severe pneumonia or acute respiratory failure requiring extracorporeal oxygenation membrane support (2,3). From these findings, it is evident that the potential benefits of this paradox derive from two aspects of a high BMI, that related to muscle mass and that related to adipose tissue.…”

“…Numerous studies have consistently demonstrated that obese patients with sepsis tend to have better survival rates than those nonobese patients, suggesting a potential protective effect of excess body weight (1). In addition to Western populations, recent research conducted by Yeo et al (2) indicated that obese Asian patients with sepsis may also benefit from a similar survival advantage. In their study, obesity was associated with better in-hospital survival and functional outcomes at discharge.…”

“…From these findings, it is evident that the potential benefits of this paradox derive from two aspects of a high BMI, that related to muscle mass and that related to adipose tissue. We found that the proportion of muscle mass to body mass is more prognostic in extremely critical illnesses (2). This year's data, published in Critical Care Medicine, consistently showed that obesity (high BMI) protects against functional loss in sepsis survivors, leading to better survival rates (4).…”

“…Hye Ju Yeo, MD [1][2][3] Woo Hyun Cho, MD [1][2][3] The authors reply: W e read the comments by Lee (1) with great interest. Thus far, several hypotheses for the obesity paradox have been proposed, but they are inconclusive.…”

The authors reply

“…We found that the proportion of muscle mass to body mass is more prognostic in extremely critical illnesses (2). This year’s data, published in Critical Care Medicine , consistently showed that obesity (high BMI) protects against functional loss in sepsis survivors, leading to better survival rates (4). However, the priority afforded a lack of muscle mass or the fat mass ratio in the data needs to be clarified (4), with support for this hypothesis provided by evidence of the impact of a high BMI on sarcopenia and the clinical outcome of severe disease.…”