Serum vitamin D levels and olfactory function in adults: a cross-sectional study with dose–response and ROC analysis
European Archives of Oto-Rhino-Laryngology, cilt.283, sa.8, ss.5115-5122, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 283 Sayı: 8
- Basım Tarihi: 2026
- Doi Numarası: 10.1007/s00405-026-10327-4
- Dergi Adı: European Archives of Oto-Rhino-Laryngology
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, BIOSIS, EMBASE, MEDLINE, Academic Search Ultimate (EBSCO), Biomedical Reference Collection: Corporate Edition (EBSCO), Health Research Premium Collection (ProQuest)
- Sayfa Sayıları: ss.5115-5122
- Anahtar Kelimeler: Vitamin D, Olfactory function, Odor threshold, Odor identification, Sniffin' Sticks, Dose-response, ROC analysis
- Sağlık Bilimleri Üniversitesi Adresli: Evet
Özet
Purpose: The purpose of this study was to examine the relationship between serum 25(OH)D levels and olfactory function in adults, given the emerging recognition of vitamin D as a neurosteroid with potential influence on sensory pathways. Specifically, the study aimed to determine whether vitamin D status is associated with olfactory threshold and identification performance, to explore the presence of a biologically plausible dose–response pattern, and to assess the predictive value of serum vitamin D levels for olfactory dysfunction. Methods: In this cross-sectional study, 161 adults were enrolled, including 98 with vitamin D deficiency and 63 with sufficient levels. Serum 25(OH)D was measured by HPLC and categorized into four groups (< 10, 10–20, 20–30, ≥ 30 ng/mL). Olfactory threshold and identification were assessed using the Sniffin’ Sticks rapid screening kit. Group comparisons, subgroup analyses, correlation tests, multiple linear regression, and ROC analysis (threshold < 7) were performed. Results: Vitamin D–deficient participants had significantly lower threshold and identification scores than controls (p = 0.008 and p < 0.001). Both scores increased stepwise across vitamin D subgroups (p < 0.001). Serum 25(OH)D correlated positively with threshold (r = 0.302) and identification (r = 0.432) (both p < 0.001); in the deficiency group, the correlation persisted only for threshold. Vitamin D was an independent predictor of identification (β = 0.041; p < 0.001). ROC analysis indicated that severe vitamin D deficiency (cutoff ≈ 10 ng/mL) was strongly associated with threshold-level olfactory impairment (AUC 0.636; specificity 95%). Conclusion: Serum vitamin D level is associated with olfactory function, particularly odor identification, and shows a biologically plausible dose–response pattern. Vitamin D appears to be a specific risk indicator rather than a standalone diagnostic marker for olfactory dysfunction.