Association between postoperative glutamine supplementation and short-term outcomes after ileostomy reversal in patients with colorectal cancer: a retrospective cohort study

Introduction Ileostomy reversal is associated with substantial postoperative morbidity despite being considered a relatively minor surgical procedure. Although glutamine supplementation has been investigated in gastrointestinal surgery, evidence regarding its role in patients undergoing ileostomy reversal remains limited. This study evaluated the association between postoperative glutamine supplementation and short-term outcomes following ileostomy reversal in patients with colorectal cancer. Methods This retrospective cohort study included consecutive patients with colorectal cancer who underwent elective ileostomy reversal between January 2015 and December 2025. Patients were classified into the glutamine group, who received postoperative intravenous glutamine supplementation, and the control group. Postoperative outcomes within 30 days, including complications, gastrointestinal recovery, and length of hospital stay, were compared between groups. Results A total of 183 patients were included, comprising 103 patients in the glutamine group and 80 in the control group. After 1:1 propensity score matching (PSM), 74 matched pairs were identified. Compared with the control group, the glutamine group had a significantly lower incidence of overall postoperative complications (14.9% vs. 29.7%, P = 0.043) and infectious complications (9.5% vs. 23.0%, P = 0.041). The glutamine group also had shorter times to first flatus, first defecation, and initiation of oral diets, as well as lower incidences of postoperative nausea and vomiting and abdominal distension. Hospital stay was shorter in the glutamine group. No significant between-group differences were observed in postoperative serum prealbumin, total protein, or albumin levels. Conclusions In this PSM study, postoperative glutamine supplementation was associated with fewer postoperative complications, faster gastrointestinal recovery, and shorter hospital stay following ileostomy reversal in patients with colorectal cancer. These findings indicate a potential association between glutamine supplementation and favorable short-term postoperative outcomes and warrant confirmation in prospective randomized studies.