Serum Otoconin-90 and Otolin-1 Levels in Benign Paroxysmal Positional Vertigo

Objective: To evaluate the value of otolith‑associated protein otoconin‑90 (OC90) and otolin-1 in the pathogenesis research and clinical treatment of benign paroxysmal positional vertigo (BPPV). Material and Method: The study included 50 patients with BPPV admitted to neurology and otorhinolaryngology departments and 30 healthy subjects with no history of dizziness as control group. Results: BPPV and controls were similar in terms of gender and age. Otolin-1 level was significantly greater in the BPPV group than controls (710.44 vs 280.45 ; p<0.001). No statistical significance was found although OC90 were higher in the BPPV group than controls. There was a strong positive correlation between otolin-1 and OC90, a moderate negative correlation between otolin-1 and vitamin D, and a strong negative correlation between OC90 and vitamin D in BPPV patient group. Otolin-1 had high specificity and AUC values for BPPV (AUC: 0.933; 95% CI: 0.881-0.986, 79.2% sensitivity, 100% specificity with a cutoff greater than 525). Conclusion: High serum levels of otolin-1 were associated with an increased risk of BPPV, but not CO90. Serum levels of otolin-1 can potentially be used as a biomarker for acute onset of inner ear disorders due to its significant increase in patients with BPPV. Vitamin D has high specificity and sensitivity in the patients with BPPV patients. It also provides evidence that BPPV patients with vitamin D deficiency may improve their complaints with replacement therapy. More large-scale prospective studies is required to confirm these association and clarify the exact mechanism.