Visceral fat area is a better indicator of surgical outcomes after laparoscopic gastrectomy for cancer than the body mass index: a propensity score-matched analysis.

ABSTRACT

BACKGROUND: The number of overweight gastric cancer patients who are undergoing laparoscopic gastrectomy (LG) has increased in Japan. However, the relationship between obesity and surgical outcomes of LG remains unclear. Therefore, this study aimed to evaluate the effect of visceral fat area (VFA) on surgical outcomes of LG for gastric cancer compared to the body mass index (BMI). METHODS: This study was a retrospective, cohort study that included 587 patients who underwent LG in our institution between January 2015 and December 2019. The patients were divided into two groups according to VFA (< 100 cm2 and ≥ 100 cm2) and BMI (< 25 kg/m2 and ≥ 25 kg/m2) values, respectively. Surgical outcomes and postoperative complications were compared between the low and high groups for each VFA and BMI value. Propensity score matching was used to minimize potential selection bias. RESULTS: After propensity score matching, 144 pairs of patients in the VFA group and 82 pairs of patients in the BMI group were extracted. Operative time (p = 0.003), intraoperative blood loss (p = 0.0006), and CRP levels on postoperative day 1 (p = 0.002) and on postoperative day 3 (p = 0.004) were significantly higher in the high-VFA group than in the low-VFA group. However, these surgical outcomes were not significantly different between the high-BMI and low-BMI groups. There was no strong correlation between VFA and BMI (R2 = 0.64). There were no significant differences in postoperative complications between the high and low groups for both VFA and BMI values. On multivariate analysis, high VFA was an independent predictor of operative time, but it was not significantly associated with the incidence of postoperative complications. CONCLUSION: VFA is a better indicator of longer operative time than BMI. However, increased VFA did not affect postoperative complications.