Meta-Analysis
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World J Gastroenterol. Jul 28, 2013; 19(28): 4596-4606
Published online Jul 28, 2013. doi: 10.3748/wjg.v19.i28.4596
Impact of being overweight on the surgical outcomes of patients with gastric cancer: A meta-analysis
Xiang-Song Wu, Wen-Guang Wu, Mao-Lan Li, Jia-Hua Yang, Qi-Chen Ding, Lin Zhang, Jia-Sheng Mu, Jun Gu, Ping Dong, Jian-Hua Lu, Ying-Bin Liu
Xiang-Song Wu, Wen-Guang Wu, Mao-Lan Li, Jia-Hua Yang, Qi-Chen Ding, Lin Zhang, Jia-Sheng Mu, Jun Gu, Ping Dong, Jian-Hua Lu, Ying-Bin Liu, Department of General Surgery, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200092, China
Author contributions: Wu XS, Wu WG and Liu YB designed research; Li ML, Yang JH, Ding QC and Zhang L performed research; Mu JS, Gu J, Dong P and Lu JH contributed new reagents or analytic tools; Wu XS, Wu WG, Lu JH and Liu YB analyzed data; Wu XS, Wu WG and Liu YB wrote the paper; Wu XS and Wu WG contributed equally to this work.
Correspondence to: Ying-Bin Liu, MD, PhD, Department of General Surgery, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, 1665 Kongjiang Rd, Shanghai 200092, China. liuybphd@126.com
Telephone: +86-21-25077880 Fax: +86-21-25077880
Received: April 15, 2013
Revised: May 31, 2013
Accepted: June 19, 2013
Published online: July 28, 2013
Abstract

AIM: To investigate the effect of being overweight on the surgical results of patients with gastric cancer.

METHODS: Comprehensive electronic searches of the PubMed, Web of Science, and Cochrane Library databases were conducted. Studies were identified that included patients with surgical complications from gastric cancer who were classified as normal weight [body mass index (BMI) < 25 kg/m2] or overweight (BMI ≥ 25 kg/m2). The operative time, retrieved lymph nodes, blood loss, and long-term survival were analyzed. A subgroup analysis was conducted based on whether patients received laparoscopic or open gastrectomy procedures. All statistical tests were performed using ReviewerManager 5.1.2 software.

RESULTS: This meta-analysis included 23 studies with 20678 patients (15781 with BMI < 25 kg/m2; 4897 with BMI ≥ 25 kg/m2). Overweight patients had significantly increased operation times [MD: -29.14; 95%CI: -38.14-(-20.21); P < 0.00001], blood loss [MD: -194.58; 95%CI: -314.21-(-74.95); P = 0.001], complications (RR: 0.75; 95%CI: 0.66-0.85; P < 0.00001), anastomosis leakages (RR: 0.59; 95%CI: 0.42-0.82; P = 0.002), and pancreatic fistulas (RR: 0.486; 95%CI: 0.34-0.63; P < 0.00001), whereas lymph node retrieval was decreased significantly in the overweight group (MD: 1.69; 95%CI: 0.75-2.62; P < 0.0001). In addition, overweight patients had poorer long-term survival (RR: 1.14; 95%CI: 1.07-1.20; P < 0.0001). No significant difference was detected for the mortality and length of hospital stay.

CONCLUSION: This meta-analysis demonstrates that a high BMI not only increases the surgical difficulty and complications but also impairs the long-term survival of patients with gastric cancer.

Keywords: Overweight, Body mass index, Gastric cancer, Gastrectomy

Core tip: Surgical and postoperative complications are believed to be greater for overweight patients with gastric cancer, but this is controversial due to conflicting results from previous studies. This meta-analysis identified 23 studies with a total of 20678 patients, and the results indicate that overweight patients had significantly increased operation times, blood loss, complications, anastomosis leakages, and pancreatic fistulas, whereas lymph node retrieval was decreased significantly in the overweight group. In addition, overweight patients had poorer long-term survival. Therefore, being overweight not only increased the surgical difficulty and complications but also impaired the long-term survival of patients with gastric cancer.