Enteral Versus Parenteral Nutrition in Patients Undergoing Hematopoietic Stem Cell Transplantation: A Systematic Review and Meta-Analysis
Authors: Peng Fucong , Zhang Huijuan , Xie Wenjun , Jiang Erlie 
Published: December 2023

Purpose : The purpose of this study is to conduct a systematic review to compare the nutritional support level, tolerance, and clinical outcomes obtained with enteral and parenteral nutrition in patients undergoing hematopoietic stem cell transplantation(HSCT).
Methods: A computerized search of studies published from database inception to June 12, 2023 was conducted in English language databases including Pubmed, Cochrane Library, Embase, and Web of Science, and in Chinese language databases including China National Knowledge Infrastructure (CNKI), Wanfang Database, VIP Database, and Chinese Biomedical Literature Database (Sinomed). The search strategy was constructed using a combination of subject headings and free-text terms. Search terms included “Stem Cell Transplantat*” “Bone Marrow Transplantation” “Enteral Nutrition” “Parenteral Nutrition”. The inclusion criteria for this intervention study are studies that include patients undergoing hematopoietic stem cell transplantation and compare enteral nutrition versus parenteral nutrition as an intervention. The outcome measures include changes in patient nutritional status, nutritional support tolerance, incidence of infection, incidence of GVHD, length of hospital stay, and number of days to neutrophil engraftment. Studies including conference abstracts and those without full-text availability were excluded.
Results: A total of 3,175 relevant articles were identified through the search, and after duplicates and screening, 10 studies with 339 patients were included. The literature screening process is shown in Figure 1, and the included study characteristics are presented in Table 1. The average duration of enteral nutrition in HSCT patients was 10-16 days, while parenteral nutrition lasted on average 14-17.5 days. Nasogastric tube feeding provided 50%-90% of the required nutrition, while intravenous nutrition provided 58%-97% of the required nutrition. Meta-analysis results showed that patients receiving enteral nutrition had a higher degree of weight loss compared to those receiving parenteral nutrition after HSCT [MD=1.97, 95%CI(0.81, 3.12), P&lt;0.001], but had a lower degree of serum albumin decline [MD=2.49, 95%CI(0.82, 4.17), P=0.003], as shown in Figures 2-3. In terms of tolerance, 45%-100% of patients switched from enteral to parenteral nutrition before completing nutritional support, with common reasons being repeated tube displacement, inability to meet nutritional demands, nausea, and diarrhea. Only one study reported bleeding rates, which were 23% for the enteral nutrition group and 30% for the parenteral nutrition group. Meta-analysis results showed no significant differences in the incidence of grade 3-4 GVHD, grade 3-4 gastrointestinal mucositis, incidence of infection, and mean length of hospital stay between the two groups, as shown in Figures 4-7. The quality assessment of included studies is presented in Figure 8.
Conclusion: Previous studies have suggested that enteral nutrition may be a cost-effective alternative to parenteral nutrition and could potentially prevent bacterial translocation by stimulating the gastrointestinal mucosa. The American Society for Parenteral and Enteral Nutrition recommends that enteral nutrition should be prioritized for HSCT patients who cannot meet their nutritional needs through oral intake. This study found that enteral and parenteral nutrition provided similar levels of nutritional support, and there were no statistically significant differences in clinical outcomes, such as the incidence of grade 3-4 GVHD, grade 3-4 gastrointestinal mucositis, incidence of infection, and mean length of hospital stay. However, based on patient tolerance, factors such as repeated tube displacement, inability to meet nutritional demands, nausea, and diarrhea may lead to the removal of the tube before reaching the nutritional target, and a switch to parenteral nutrition support. Therefore, when choosing enteral nutrition support, it is essential to evaluate the patient's nutritional needs, nasal and skin mucosa condition, and gastrointestinal function. As the studies included in this review were small sample studies, there may be some bias in the results. Future multi-center, large-sample prospective studies are needed to further compare the risks and benefits of different nutritional support modalities for HSCT patients.