Effect of nutritional support on clinical outcomes in perioperative malnourished patients: a meta-analysis

Malnutrition is an independent risk factor for complications, mortality, wound healing, length of hospital stay, and costs. Associations between nutritional support and surgical patients remain controversial. Databases, including Pubmed, EMBASE, Web of Science, CNKI, VIP, and the Cochrane Library, were searched to find randomized controlled trials (RCTs) that assessed the effect of nutritional support on clinical outcomes in perioperative malnourished patients. The methodological quality of each included trial was assessed. A meta-analysis was conducted with Rev Man 5.2. Fifteen RCTs, involving 3831 patients, were included in this meta-analysis. Compared with control group, results showed that nutritional support was more effective in decreasing the incidence of infectious [relative risk (RR): 0.58; 95% CI: 0.50, 0.68; p<0.01] and non-infectious complications (RR: 0.74; 95% CI: 0.63, 0.88; p<0.01), and shortening the length of hospital stay [weighted mean difference (WMD): -2.64; 95% CI: -5.13, -0.16; p<0.05]. Moreover, the incidence of infectious complications in the immune nutrition group was significantly lower than that in the standard nutrition group (RR: 0.75; 95% CI: 0.58, 0.97; p<0.05). However, changes in hospital costs (WMD: 894; 95% CI: -1140, 2928; p>0.05) and postoperative mortality (RR: 0.77; 95% CI: 0.41, 1.44; p>0.05) between the nutritional support group and control group were not significantly different. In conclusion, perioperative nutritional support was superior in improving clinical outcomes in malnourished patients, which could significantly reduce the incidence of complications and effectively shorten the length of hospital stay.