The amount of visceral adipose tissue (VAT) quantitatively measured by abdominal computed tomography is dose-dependently associated with mortality in sepsis

Abstract

Introduction: Adipose tissue is recognized as not only an energy reservoir, but also an endocrine organ producing proinflammatory cytokines. An impact of visceral adipose tissue in critical illnesses has been proposed, but research regarding the association between visceral adipose tissue and sepsis is scant, and visceral adipose tissue has not been quantitatively measured. Methods: In this retrospective cohort study, we enrolled patients admitted to our intensive care unit with sepsis who had abdominal computed tomography within 1 month of occurrence of sepsis. Age, sex, anthropometric values, comorbidities, Acute Physiology and Chronic Health Evaluation II score, source of infection, and appropriateness of antibiotics were reviewed. The areas of visceral adipose tissue and total adipose tissue on the section of abdominal computed tomography image of the umbilicus or L4-5 level were measured by calculating pixels presenting fat density. Results: Among 310 patients admitted because of sepsis, 178 patients were finally included in this study. Median age was 65 years and 59.0% were men. In-hospital mortality rate was 59.0%. Women had more total and subcutaneous adipose tissue and a lower visceral/total adipose tissue ratio compared with men. The amount of visceral adipose tissue and the visceral/total adipose tissue ratio were higher in the in-hospital mortality group than in the group of survivors (92.00 cm2 vs. 60.82 cm2 and 45.88% vs. 32.79%, P < 0.001 and <0.001, respectively). After adjusting for age, sex, comorbidities, Acute Physiology and Chronic Health Evaluation II score, source of infection, and appropriateness of antibiotics, a multiple logistic regression analysis revealed that the amount of visceral adipose tissue and visceral/total adipose tissue ratio were independent prognostic factors of sepsis with an obvious dose-dependent relationship (visceral adipose tissue/total adipose tissue ratio quartile 3: odds ratio 8.529, P < 0.001 and quartile 4: odds ratio 35.772, P < 0.001, compared with quartile 1, respectively). Conclusions: The amount of visceral adipose tissue and visceral adipose tissue/total adipose tissue ratio quantitatively measured by abdominal computed tomography were positively correlated with mortality in sepsis, and this association was dose dependent. Visceral obesity should be considered as the poor prognostic factor of sepsis.