Association between sex-specific criteria for visceral obesity and surgical site infection after gastrectomy

Background: High visceral fat area (VFA), estimated by computed tomography (CT), is reportedly associated with surgical site infection (SSI) in patients who undergo gastrectomy for gastric cancer (GC). Given that fat distributions vary markedly according to sex, sex-specific definitions of visceral obesity should be applied. This study investigated the optimal sex-specific thresholds for VFA at the L3 level to assess the risk of SSI after gastrectomy.

Methods: This study included 828 patients (564 males and 264 females) who underwent curative gastrectomy. Intra-abdominal or incisional infectious complications with Clavien-Dindo scores ≥ 2 were defined as SSIs. Receiver operating characteristic (ROC) analyses were used to determine the optimal sex-specific VFA cutoffs to extract patients with obesity who are at risk of developing SSI. In addition, logistic regression analyses were performed, and the corrected Akaike information criterion (AICc) was calculated to compare the capability to evaluate the possibility of SSI of our sex-specific VFA-based criteria vs the conventional VFA-based or body mass index (BMI)-based criterion.

Results: SSI developed in 59 males and 16 females. Optimal VFA thresholds were 119.3 cm² for males and 57.2 cm² for females. Multivariate analyses revealed visceral obesity, as defined by the sex-specific criteria, to be an independent risk factor for SSI (odds ratio, 2.74; 95% CI, 1.62-4.66; P <.01). The logistic regression model with our sex-specific criteria yielded a better AICc (456.4) than the conventional (461.8) or BMI-based (467.0) criterion for obesity.

Conclusion: Sex-specific criteria can enhance the capability of VFA to assess the risk of SSI after gastrectomy, compared with the non-sex-specific criterion.