The Impact of Preoperative Underweight Status on Postoperative Complication and Survival Outcome of Gastric Cancer Patients: A Systematic Review and Meta-analysis.

OBJECTIVE

In this study, we performed a systematic review and meta-analysis to evaluate the impact of preoperative underweight status on postoperative complications and survival outcome of gastric cancer (GC) patients.

METHODS

The related studies were identified by searching PubMed and Embase databases. According to the body mass index (BMI), all patients were classified into underweight group (<18.5 kg/m) and normal weight group (≥18.5 kg/m, <25 kg/m). The relevant data were extracted and pooled effect size were assessed using a fixed effect model or random effect model.

RESULTS

A total of 12 studies were included in this meta-analysis. The results indicated that underweight patients had a higher risk of postoperative complications than normal weight patients (RR: 1.28, 95% CI: 1.01-1.61, P < 0.05; I = 57.3%), especially for pulmonary infection (RR: 1.58, 95% CI: 1.03-2.43, P < 0.05; I = 47.7%). However, there was no significant difference between underweight and normal weight patients for major surgery-related complications such as anastomotic leakage, wound infection, and intra-abdominal infection. In addition, the short-term (RR: 2.12, 95% CI: 1.47-3.06, P < 0.001; I = 0%) and long-term survival (HR: 1.53, 95% CI: 1.14-2.07, P < 0.01; I = 64.0%) of underweight patients was significantly poorer than that of normal weight patients.

CONCLUSION

Preoperative underweight status was significantly associated with unfavorable postoperative outcome of GC patients. The status may represent excessive nutritional consumption and malnutrition resulting from aggressive tumor.