Analysis of Risk Factors for Olfactory Dysfunction in CRSsNP Patients: A Prospective Case-Control Study

This study aimed to identify the risk factors associated with olfactory dysfunction (OD) in patients with chronic rhinosinusitis without nasal polyps (CRSsNP), a prevalent condition where impaired smell significantly reduces quality of life. The goal was to provide insights for improving clinical management strategies.

A prospective study was conducted on patients undergoing endoscopic surgery. CRSsNP patients were categorized into an OD group (n = 36) and a normosmic group (n = 36) based on olfactory tests, with 21 septoplasty patients as healthy controls. Demographic and clinical data were analyzed. Logistic regression and receiver operating characteristic (ROC) curves were used to identify independent risk factors and assess their predictive value.

A total of 93 subjects were included. Comparative analysis revealed no significant differences in age, body mass index, sex, disease duration, smoking history, drinking history, diabetes, or hypertension among the 3 groups. However, the OD group exhibited significantly lower nasal cavity volume and counts of mucosal olfactory marker protein-positive cells (STOMP). Conversely, they had significantly higher sinusitis severity scores (Lund-Mackay CT), nasal endoscopic scores (Lund-Kennedy), interleukin-5 (IL-5) levels, total serum immunoglobulin E (IgE), olfactory detection/recognition thresholds, and olfactory visual analog scale scores. Multivariate analysis confirmed that nasal cavity volume, Lund-Mackay score, Lund-Kennedy score, IL-5, IgE, and STOMP were independent influencing factors for OD. Correlation analysis further supported these findings. The ROC curve analysis validated that all these parameters had significant predictive value for identifying OD, with area under the curve values all >0.6.

Nasal cavity volume, Lund-Mackay CT score, Lund-Kennedy endoscopy score, IL-5, IgE, and STOMP are significantly and independently associated with OD in CRSsNP patients. These parameters demonstrate efficacy in screening for olfactory abnormalities, enabling early identification and providing a valuable reference for optimizing clinical therapeutic strategies to improve patient outcomes.