Allergic rhinitis and aspirin-exacerbated respiratory disease as predictors of the olfactory outcome after endoscopic sinus surgery.

Background: Unlike the functional outcomes of endoscopic sinus surgery, which have been thoroughly studied, the effect of the surgery on olfactory performance and the relative predictive factors have not been adequately assessed by literature. Allergic rhinitis and aspirin-exacerbated respiratory disease (AERD) are examined as potential confounding factors of the olfactory outcome in patients with extensive nasal polyposis and rhinosinusitis treated with functional endoscopic sinus surgery (FESS).

Methods: A population of 116 adults with severe nasal polyposis was subjected to FESS after failure of the appropriate medical treatment. The olfactory outcome was quantified by Sniffin' Sticks at the 1st, 3rd, and 6th postoperative month in relation to the concomitant presence of allergic rhinitis (n = 62) or AERD (n = 18).

Results: Allergic patients seemed to perform worse than nonallergic patients at all time frames. However, when patients with similar olfactory acuity, age, and medical history are compared, allergic rhinitis does not seem to affect the postoperative improvement of the composite threshold-discrimination-identification scores. The same seems to apply for the likelihood of acquiring normosmia after surgery. On the contrary, AERD significantly limits the recovery of olfactory function at all follow-up examinations and patients with AERD are unlikely to become normosmic.

Conclusion: The olfactory recovery after FESS for nasal polyposis is significantly affected by the concomitant presence of AERD. Although allergy seems to have a general negative effect on olfactory acuity, it was not found to affect the extent of the olfactory improvement, when patients with comparable preoperative characteristics are addressed.