Impact of high body mass index on surgical outcomes and long-term survival among patients undergoing esophagectomy: A meta-analysis.

Background: The impact of high body mass index (BMI, >23/25kg/m(2)) on surgical outcomes and prognosis in patients with esophageal carcinoma (EC) after undergoing esophagectomy remains controversial. We herein conducted a systematic review and meta-analysis to determine the relationship between high BMI and surgical outcomes and prognosis in patients undergoing esophagectomy for EC. Methods: The study search was conducted by retrieving publications from the PubMed, Embase, Web of Science, and CNKI (up to September 8, 2017). Nineteen studies with 13,756 patients were included in this meta-analysis. Results: We found that high BMI was closely associated with a higher incidence of wound infection (odds ratio [OR]: 1.41, 95% confidence interval [CI]: 1.02-1.97, P=.04), cardiovascular complications (OR: 2.51, 95% CI, 1.65-3.81, P<.0001), and anastomotic leakage (OR: 1.50, 95% CI, 1.21-1.84, P=.0002), but a lower incidence of chylous leakage (OR: 0.59, 95% CI, 0.40-0.88, P=.01) when compared with normal BMI. The high BMI group was not associated with better or worse overall survival (OS) (hazard ratio [HR]: 0.95, 95% CI, 0.85-1.07, P=.4) and disease-free survival (HR: 0.95, 95% CI, 0.72-1.25, P=.72) than the normal BMI group. However, in the subgroup analysis, the pooled result of HRs generated from multivariate analyses suggested that high BMI could improve OS in EC patients (HR: 0.84, 95% CI, 0.76-0.93, P<.01). Conclusions: Overweight patients with EC should not be denied surgical treatment, but intraoperative prevention and careful postoperative monitoring for several surgical complications must be stressed for this population. Besides, high BMI might be a prognostic predictor in EC patients; further studies are warranted.