Effect of Omega-3 Supplementation in Patients with Olfactory Dysfunction following Endoscopic Sellar and Parasellar Tumor Resection

Introduction: Endoscopic endonasal approaches to the anterior skull base for sellar and parasellar masses pose the potential risk of postoperative olfactory loss. Although usually temporary, loss of olfaction and potentially taste can be permanent and greatly affect patients’ quality of life. Medical treatments for olfactory loss have had limited success. Omega-3 supplementation has proven beneficial for wound healing and nerve regeneration. This study evaluated the impact on olfaction in patients treated with omega-3 supplementation following endoscopic skull base tumor resection.

Methods: In this multi-institutional, prospective, randomized controlled trial, 108 patients with sellar or parasellar tumors undergoing endoscopic endonasal resection were randomized to nasal saline irrigations alone or nasal saline irrigations plus omega-3 supplementation (2,000 mg daily). The University of Pennsylvania Smell Identification Test (UPSIT) was administered preoperatively and again at 6 weeks, 3 months, and 6 months postoperatively.

Results: Eighty-seven patients completed the study with at least 6-month follow-up (control arm: 41; omega-3 arm: 46). There were no significant (p < 0.05) differences in patient demographics, tumor characteristics, or baseline olfactory function between the two groups. At 6 weeks postendoscopic endonasal surgery, 25% of patients in both groups experienced a clinically significant loss in olfaction, based on UPSIT score. At 3 months and 6 months postoperatively, patients receiving omega-3 supplementation demonstrated significantly less persistent olfactory loss compared with patients without supplementation (p = 0.02 and p = 0.01, respectively). After controlling for confounding variables, such as tumor size, type, and location, omega-3 supplementation was found to be protective against olfactory loss (odds ratio [OR]: 0.05, 95% confidence interval [CI]: 0.003–0.81, p = 0.03). The presence of a functioning pituitary adenoma was a significant independent predictor for postoperative olfactory loss (OR: 32.7, 95% CI: 1.15–929.5, p = 0.04).

Conclusion: Omega-3 supplementation appears to be protective for the olfactory system during the healing period in patients who undergo endoscopic resection of their sellar and suprasellar masses, and may be a useful treatment to prevent an expected temporary impairment from becoming permanent.