Analysis of risk factors affecting olfactory dysfunction in patients with chronic rhinosinusitis: Highlighting the role of metabolic syndrome.

Objective: This study aims to evaluate the relationship between chronic sinusitis (CRS) and metabolic syndrome (MS) in a Chinese population and to explore the risk factors for olfactory dysfunction in patients with CRS. Methods: A total of 387 CRS patients were enrolled. Olfactory function was assessed by the Sniffin' Sticks 12-item test and MS was diagnosed according to the guidelines. Logistic regression analysis was performed on CRS patients to screen independent risk factors of olfactory dysfunction, adjusted for confounding factors. Results: Among 387 patients, average age of visit and duration of onset were 48.7 years and 1.8 years, respectively. The prevalence of MS was 15.0%. CRS patients with MS were more likely to be older (51.2 vs. 46.8, p = .004), predominantly male (p < .001) and have a higher proportion of olfactory dysfunction (62.1% vs. 44.1%, p = .018) than those without MS. In multivariate logistic regression analysis, MS was associated with olfactory dysfunction in CRS patients (OR: 2.06, 95% CI: 1.14-3.72, p = .016). This association remained significant after controlling for confounding factors. In addition, nasal polyps (OR: 13.41, 95% CI: 8.11-22.17, p < .001) and allergic rhinitis (OR: 3.16, 95% CI: 1.67-5.99, p < .001) were also risk factors for olfactory dysfunction after adjusting for confounding factors. Conclusions: MS is associated with olfactory dysfunction in patients with CRS. MS, nasal polyps, and allergic rhinitis are risk factors for olfactory dysfunction in CRS patients. Level of evidence: IV.