Background: There is no known predictor for olfactory function recovery with dupilumab treatment in chronic rhinosinusitis with nasal polyps (CRSwNP). This study assessed whether patient-reported recovery of olfactory function on oral corticosteroids (OCS) is a prognostic factor.
Methods: Retrospective analysis of pre-biological OCS-responsiveness on olfactory functioning (OCS-responsive or OCS-unresponsive; OCS-r and OCR-u, respectively) as predictor for olfactory functioning after 6 months of dupilumab therapy for severe CRSwNP.
Results: 212 CRSwNP patients treated with dupilumab were divided between OCS-r (reported improvement of olfactory function with OCS before dupilumab treatment, n = 152), and OCS-u (OCS-unresponsive; no such improvement, n = 60). Olfactory function was tested with Sniffin' Sticks Identification Test (12 pens; SSIT-12). At baseline, both groups had a median SSIT-12 score of 3 / 12 indicating anosmia. Hyposmia and normosmia rates were also comparable (5.9% and 3.3% in OCS-r, respectively; 5.0% and 1.7% in OCS-u, respectively). After 6 months of dupilumab treatment, OCS-r showed higher olfactory scores (median SSIT-12: 8/12; 52.6% hyposmia and 17.8% normosmia) than OCS-u (median SSIT-12: 5/12; 31.7% hyposmia and 3.3% normosmia). The positive predictive value of OCS-responsiveness on scoring ≥7 (normosmia/hyposmia) on the SSIT-12 after 6 months of dupilumab treatment was 70.4%. Conversely, the negative predictive value of OCS-unresponsiveness on scoring.