Functional and gain-based vestibulo-ocular measures across serum 25(OH)D categories: a dissociation between fHIT performance and vHIT gain
Acta Oto-Laryngologica, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Basım Tarihi: 2026
- Doi Numarası: 10.1080/00016489.2026.2755224
- Dergi Adı: Acta Oto-Laryngologica
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, CINAHL, EMBASE, MEDLINE, Academic Search Ultimate (EBSCO), Biomedical Reference Collection: Corporate Edition (EBSCO), Psychology & Behavioral Sciences Collection (EBSCO)
- Anahtar Kelimeler: Functional head impulse test, vestibular evoked myogenic potentials, vestibulo-ocular reflex, video head impulse test, vitamin D
- İstanbul Gelişim Üniversitesi Adresli: Evet
Özet
Background: Conventional vestibular tests quantify canal and otolith function, whereas the functional head impulse test (fHIT) measures how effectively the vestibulo-ocular reflex stabilizes vision during high-acceleration head motion. Low 25-hydroxyvitamin D [25(OH)D] has been linked to otolith dysfunction, but its relation to functional performance is unknown. Objectives: To compare otolith, canal and functional measures across serum 25(OH)D categories in adults without overt vestibular disease. Materials and methods: Thirty-nine adults aged 18–65 years with normal hearing were stratified by serum 25(OH)D into three groups of 13 (<20, 20–29.9, ≥30 ng/mL). All underwent audiometry, videonystagmography, cVEMP, oVEMP, vHIT and fHIT. Kruskal–Wallis and Mann–Whitney U tests were used. Results: fHIT correct response rates differed for posterior (p = 0.001) and anterior canals (p = 0.019), being lowest at <20 ng/mL; lateral performance was preserved (p = 0.234). All vHIT gains remained within acceptable limits and only anterior canal gain differed (p = 0.001). VEMP latencies were comparable; cVEMP amplitude asymmetry differed (p = 0.023) but opposite to expectation and within normal range. Conclusions and significance: Low 25(OH)D was accompanied by reduced functional vestibulo-ocular performance in the vertical canal planes despite normal gains. fHIT may capture subclinical change that vHIT gain does not.