Olfactory-specific quality of life outcomes after endoscopic sinus surgery

Background: Olfactory loss is a cardinal symptom of chronic rhinosinusitis (CRS) and affects 40% to 80% of patients. However, common sinus-specific quality-of-life (QOL) instruments include only single questions related to olfaction. Few studies have explored olfactory outcomes after surgery utilizing validated, olfaction-specific QOL questionnaires. Methods: Patients with CRS were enrolled from 3 centers across North America into a prospective cohort study. Patients completed the short modified version of the Questionnaire of Olfactory Disorders (QOD-NS) and the 40-item Smell Identification Test (SIT-40) before and at least 6 months after endoscopic sinus surgery (ESS). Multivariate linear regression was used to determine whether specific demographic, comorbidity, or disease severity measures were independently associated with QOD scores at baseline or predicted change after surgery. Results: A total of 121 patients, equally split between genders, were enrolled with an average age of 47.9 years (range, 18-80 years). Baseline total QOD-NS scores were significantly associated with SIT-40 scores, with a moderate strength of correlation (Rs = 0.400; p < 0.001). The average QOD-NS score improved after ESS (35.7 ± 13.0 vs 39.7 ± 12.2; p = 0.006). Allergy, polyps, and steroid-dependent conditions were found to be independently associated with worse preoperative QOD-NS scores, whereas septal deviation was associated with better QOD-NS scores. Baseline computed tomography (CT) scores were the only variable that significantly predicted change in QOD-NS after surgery. Conclusion: Olfaction-specific QOL is worse in patients with polyps and comorbid allergy. Significant improvements in olfaction-specific QOL are seen after ESS, with the greatest gains seen in those with worse CT scores at baseline.