Structured triglyceride for parenteral nutrition: meta-analysis of randomized controlled trials

This study assessed the safety and efficacy of structured triglyceride (ST) for parenteral nutrition. A meta-analysis of all the relevant randomized controlled trials (RCTs) was performed. Clinical trials were identified from the following electronic databases: MEDLINE, EMBASE, the Cochrane Controlled Trials Register, Chinese Bio-medicine Database. The search was undertaken in March 2005. Language was restricted to Chinese and English. Literature references were checked at the same time. Only RCTs were extracted and evaluated by two reviewers independently of each other. The statistical analysis was performed by RevMan4.2 software which was provided by the Cochrane Collaboration. A P value of <0.05 was considered statistically significant. Ten RCTs involving 236 patients were included. Eight of them compared ST with the long-chain triglyceride (LCT), and the combined results showed that the ST had significant effect on resting energy expenditure (weighted mean difference [WMD] =1.54, 95%CI [ 1.26, 1.82], p<0.00001), plasma glycerol (WMD = 0.14, 95%CI [0.06, 0.22], P= 0.0007), free fatty acids (WMD=0.24, 95%CI [0.10, 0.37], P=0.0006), and beta-hydroxybutyric acid (WMD=0.14, 95%CI [0.06, 0.22], P=0.0007), but no differences was found regarding nitrogen balance (standardized mean difference [SMD] = 0.64, 95%CI [-0.30, 1.59], P=0.18), respiratory quotient (WMD =-0.02, 95%CI [-0.04, 0.01], P= 0.18), and plasma triglycerides (WMD = -0.10, 95%CI [-0.30, 0.10], P=0.32). Only two RCTs compared ST with the physical mixture of medium- and long-chain triglyceride (MCT/LCT), data from trials were not combined due to clinical differences between trials, and conclusions can not be drew from the present data. ST appeared to be safe and well tolerated. Further trials are required, especially compared with the MCT/LCT, with sufficient size and rigorous design.