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.

Figure 1.

Patient inclusion in the study. Overall, 6,424 patients were included in the study. At admission, 1,335 (20.8%) patients were obese and 5,089 (79.2%) were nonobese. Patients were divided into obese and nonobese groups according to their body mass index.

Figure 2.

Kaplan-Meier analysis. Mortality at 28 d according to obesity (χ² = 16.94; p < 0.001).

Figure 3.

Adjusted odds ratios according to WHO body mass index (BMI) classification for the three clinical outcomes. The adjusted odds ratio (OR) was calculated from the logistic regression model of the BMI group for each clinical outcome with baseline covariates.