# Visceral fat-to-muscle ratio guides spontaneous closure in post-sepsis duodenal fistula: a body composition divergence beyond visceral-subcutaneous fat ratio

## TL;DR

This study finds that a high visceral fat-to-muscle ratio predicts poor spontaneous healing in patients with duodenal fistulas after sepsis, suggesting the need for targeted nutritional support.

## Contribution

The study introduces the visceral fat-to-muscle area index (VFA/TAMAI) as a novel predictor of spontaneous closure in post-sepsis duodenal fistula patients.

## Key findings

- A VFA/TAMAI ≥3.20 independently predicts reduced likelihood of spontaneous closure (adjusted HR = 0.59).
- Incorporating VFA/TAMAI improves predictive accuracy for spontaneous closure (C-index increases from 0.67 to 0.72).
- Sensitivity analyses confirm VFA/TAMAI remains predictive after adjusting for confounding factors.

## Abstract

This study aimed to investigate whether body composition parameters (visceral fat area/total abdominal muscle area index, VFA/TAMAI; visceral-to-subcutaneous fat ratio, VFA/SFA) predict spontaneous closure in duodenal fistula patients after sepsis resolution.

A multicenter retrospective study enrolled 104 duodenal fistula patients with controlled sepsis treated between 2019 and 2025. Standardized management included infection control and nutritional support. Restricted cubic spline regression identified optimal cutoffs for VFA/TAMAI and VFA/SFA. Cox proportional hazards models evaluated associations with 90-day spontaneous closure, with inverse probability treatment weighting (IPTW) and propensity score matching (PSM) addressing confounding.

52.9% (55/104) achieved spontaneous closure within 90 days (median time: 31 days). Elevated VFA/TAMAI (≥3.20, 31.7% patients) independently predicted reduced closure likelihood (adjusted HR = 0.59, 95%CI:0.42–0.85, P = 0.004), while VFA/SFA showed no prognostic value (P > 0.05). Incorporation of VFA/TAMAI significantly improved predictive accuracy (C-index increased from 0.67 to 0.72, P = 0.013). Sensitivity analyses confirmed VFA/TAMAI≥3.20 remained predictive after IPTW adjustment (HR = 0.38, 95%CI:0.17–0.84) and PSM (HR = 0.39, 95%CI:0.19–0.83).

VFA/TAMAI serves as a robust predictor of spontaneous closure in post-sepsis duodenal fistula, with the threshold of 3.20 identifying high-risk patients requiring intensified nutritional-metabolic interventions. These findings highlight body composition monitoring as a critical adjunct to conventional nutritional management.