Parenteral n–3 polyunsaturated fatty acids supplementation improves postoperative recovery for patients with Crohn’s disease after bowel resection: a randomized, unblinded controlled clinical trial

The postoperative inflammatory response is associated with postoperative recovery in surgery. n–3 (ω-3) polyunsaturated fatty acids have been reported to lower inflammation. The postoperative role of parenteral n–3 polyunsaturated fatty acids supplementation on outcomes in Crohn's disease after bowel resection is unclear. We aimed to investigate the effects of postoperative parenteral n–3 polyunsaturated fatty acids supplementation in Crohn's disease. A prospective randomized, unblinded controlled clinical trial was conducted for patients with Crohn's disease who underwent bowel resection between May 2019 and February 2022. Postoperative complications, complete blood count, serum biochemical values, and cytokine concentrations were compared in patients with and without parenteral n–3 polyunsaturated fatty acids supplementation for 5 d postoperatively. There were 268 patients randomly assigned in the analysis, with 134 in the control group (a mix of long-chain and medium-chain fats at 1.0 g/kg/d) and 134 in the treatment group (long-chain, medium-chain, and n–3 polyunsaturated fats at 1.2 g/kg/d). Twenty-six did not complete the allocated treatment, and 8 patients were lost to follow-up. The intention–to-treat analysis and the per-protocol analysis showed that there were a significant reduction in overall complication rates (22.4% compared with 49.3%; P < 0.001 and 21.8% compared with 38.2%; P = 0.006) and postoperative stay (8.8 ± 4.5 d compared with 11.2 ± 6.8 d; P = 0.001 and 8.7 ± 4.0 d compared with 11.5 ± 7.3 d; P < 0.001) in patients with parenteral n–3 polyunsaturated fatty acids supplementation compared with patients in the control group. In the secondary outcomes, the mean ± standard deviation of interleukin (IL)-6 (17.11 ± 2.14 pg/mL compared with 30.50 ± 5.14 pg/mL; P = 0.014), IL-1β (2.01 ± 0.05 pg/mL compared with 2.24 ± 0.09 pg/mL; P = 0.019), tumor necrosis factor-α (2.09 ± 0.06 pg/mL compared with 2.29 ± 0.06 pg/mL; P = 0.029), and C-reactive protein concentrations (51.3 ± 4.2 mg/L compared with 64.4 ± 5.3 mg/L; P = 0.050) on postoperative day 5 in the treatment group were much lower than those in the control group. Parenteral n–3 polyunsaturated fatty acids supplementation promotes postoperative recovery in patients with Crohn's disease following bowel resection, with fewer complications and reduced inflammatory cytokines. This trial was registered at clinicaltrials.gov as NCT03901937 at https://classic.clinicaltrials.gov/ct2/show/NCT03901937?term=NCT03901937&cond=Crohn+Disease&draw=2&rank=1.