High visceral fat-to-muscle ratio predicated a recurrent fistula after definitive surgery for a small intestinal fistula with diffuse extensive abdominal adhesions: a cohort study.

Background: In patients diagnosed with sarcopenia, the presence of chronic preoperative inflammation, assessed by the ratio of the visceral fat area (VFA) to the total abdominal muscle area index (TAMAI) (VFA/TAMAI), has been found to adversely affect wound healing. An elevated VFA/TAMAI may contribute to a higher incidence of postoperative recurrent fistulas (RFs) following definitive surgery (DS) for small intestinal fistulas accompanied by diffuse extensive abdominal adhesions. The objective of this study was to evaluate the predictive value of VFA/TAMAI for postoperative RFs.

Methods: The study enrolled 183 sarcopenic patients, with a median age of 51 years [interquartile range (IQR): 38-61 years), a median body mass index of 19.6 kg/m 2 (IQR: 18.9-21.0 kg/m 2 ) who underwent DS for small intestinal fistulas between January 2018 and October 2022 were included in the multicenter study. The outcomes assessed were RFs and postoperative length of stay (LOS). VFA/TAMAI was examined as a potential risk factor for each outcome.

Results: Out of the 183 patients, 20.2% ( n =37) developed RFs. The multivariate regression analysis identified VFA/TAMAI as the sole factor associated with RFs [odds ratio=1.78, 95% confidence interval (CI): 1.09-2.87, P =0.02]. The multivariable Cox regression analysis demonstrated that an elevated VFA/TAMAI was linked to a reduced postoperative LOS (hazard ratio=0.69, 95% CI: 0.59-0.81, P <0.001).

Conclusion: In sarcopenic patients, a high VFA/TAMAI predicated the occurrence of RFs after DS for small intestinal fistulas in the presence of diffuse extensive abdominal adhesions.