Effects of Omega-3 Fatty Acids on Postoperative Inflammatory Response: A Systematic Review and Meta-Analysis

Abstract

Initial evidence indicates that preoperatively initiated administration of omega-3 fatty acids (FAs) attenuates the postoperative inflammatory reaction. The effects of immunonutrition containing omega-3 FAs, such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), on the inflammatory response to abdominal surgery continues to be unclear, although improved outcomes have been reported. Therefore, we determined the effectiveness of preoperatively initiated omega-3 FAs administration on postoperative inflammation defined as CRP (C-Reactive Protein), IL-6 (Interleukin 6), and WBC (White Blood Count) and potential effects on postoperative length of hospital stay (LOS) due to an improved inflammatory response. Methods: a literature search of Cochrane Library was conducted to identify all randomized controlled trials (RCTs) investigating the effects of preoperatively initiated omega-3 to standard care, placebo, or other immunonutrients excluding omega-3 FAs in patients undergoing abdominal surgery until the end of December 2022. Results: a total of 296 articles were found during the initial search. Thirteen RCTs involving 950 patients were identified that met the search criteria. These were successively analyzed and included in this meta-analysis. There was no significant difference between the groups with respect to inflammatory markers IL-6: −0.55 [−1.22; 0.12] p = 0.10, CRP: −0.14 [−0.67; 0.40] p = 0.55, WBC: −0.58 [−3.05; 1.89] p = 0.42, or hospital stay −0.5 [−1.43; 0.41] p = 0.2. Conclusion: although reduced inflammatory markers were observed, preoperative administration of omega-3 FAs immunonutrients had no significant effect on the postoperative inflammatory response in patients undergoing abdominal surgeries. Yet, results obtained from this study are inconclusive, likely attributed to the limited number of trials and patients included. Further studies are required to obtain a better educated verdict.

Effects of Omega-3 Polyunsaturated Fatty Acids, Docosahexaenoic Acid and Eicosapentaenoic Acid, on Post-Surgical Complications in Surgical Trauma Patients: Mechanisms, Nutrition, and Challenges

“…A parallel meta-analysis corroborated these results, indicating that omega-3 polyunsaturated fatty acids (PUFAs) demonstrated no significant impact on the post-operative inflammatory response in patients undergoing abdominal surgeries, despite the observed reduction in inflammatory markers [56]. These collective findings emphasize caution in endorsing preoperative omega-3 fatty acid supplementation for major gastrointestinal surgery.…”

Storage duration of human blood samples for fatty acid concentration analyses - How long is too long?

“…Nevertheless, the exact roles and implications of DHA in clinical settings warrant further investigation [11] . As such, precise quantification of DHA concentration in human serum becomes imperative, not only to discern its physiological significance but also to comprehend the broader therapeutic effects they might possess in different clinical settings.…”

Effect of Fish Oil Parenteral Emulsion Supplementation on Inflammatory Parameters after Esophagectomy

“…Omega-3 fatty acids (ω-3FA) are one of the pharmaconutrients with beneficial effects on postoperative morbidity [ 9 , 10 ]. ω-3FA are composed of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), which are essential polyunsaturated fatty acids (PUFAs) derived from fish oil, and their administration can reduce proinflammatory cytokine production and regulate eicosanoid synthesis derived from arachidonic acid (AA), which are mediators of inflammation [ 8 , 9 , 10 ]. Also, DHA and EPA are associated with reduced proinflammatory transcription factor NF-κB activation.…”

“…Also, DHA and EPA are associated with reduced proinflammatory transcription factor NF-κB activation. Furthermore, it is known that these PUFAs lead to the production of resolvins E and D, that have anti-inflammatory properties as they inhibit the migration of neutrophils and their infiltration into areas of inflammation and inhibit interleukin-1β (IL-1β) production [ 8 ].…”

“…Also, a previous review of 16 clinical trials assessing the effect of enteral immunonutrition with ω-3FA in gastrointestinal surgery patients demonstrated their benefits in reducing infectious postoperative complications and length of stay, particularly among individuals with preoperative malnutrition [ 12 ]. However, recent reviews evaluating the effect on the postoperative inflammatory response after perioperative ω-3FA administration (mainly enteral) in patients undergoing gastrointestinal surgery or EPG could not demonstrate any significant effect, although reduced inflammatory markers were observed [ 2 , 8 ]. In addition, focusing on patients who underwent EPG, they could not demonstrate any significant reduction in infectious complications or anastomotic leakage; however, it did not increase in-hospital mortality [ 2 ].…”