The association between body mass index and mortality in septic older adults

Background: There is limited evidence on the association between body mass index (BMI) and outcomes in older adults with sepsis.Objectives: The purpose of this study was to explore the relationship between BMI and the clinical outcome in the older adults with sepsis.Methods: All older adults (age 65 or older) with sepsis were analyzed retrospectively in the Intensive Care Medical Information Mart (MIMIC)-IV database. The primary outcome was 30-day mortality. The relation-ship between BMI and 30-day mortality was estimated by multivariate logistic regression model. The inter -action and stratified analysis were performed by sex, race, renal disease, congestive heart failure (CHF), diabetes, and chronic pulmonary disease.Results: The total number of participants was 6604. After adjustment for potential covariates, there was a significant correlation between BMI and 30-day mortality. A 1 kg/m(2) increase in BMI was associated with a 3 % decrease in 30-day mortality (adjusted HR = 0.97, 95 % CI: 0.96-0.98, P < 0.001). The correlation between BMI and 30-day mortality showed a statistically significant nonlinear association with an L-shaped curve (p = 0.001). Significant interactions were observed only for sex in the stratified analyses (P = 0.001).Conclusions: In this study, it was observed that a higher BMI is linked with better survival rates among older adults suffering from sepsis, while being underweight raises the risk of mortality. Notably, male patients with a higher BMI had a lower mortality risk compared to female patients.(c) 2023 Elsevier Inc. All rights reserved.