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

The aim was 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).

The study included 50 patients with BPPV admitted to neurology and otorhinolaryngology departments and 30 healthy subjects with no history of dizziness as a control group.

BPPV and controls were similar in terms of gender and age. Otolin-1 concentration was significantly greater in the BPPV group than in the controls (710.44 [584.35-837.39] vs 280.45 [212.7-419.61]; p < 0.001). No statistical significance was found, although OC90 was higher in the BPPV group than in the 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 the 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).

High serum concentrations of otolin-1 were associated with an increased risk of BPPV, but high concentrations of OC90 were not. Serum concentrations of otolin-1 can potentially be used as a biomarker for the acute onset of inner ear disorders due to the significant increase in patients with BPPV. Vitamin D has high specificity and sensitivity in patients with BPPV. It also provides evidence that BPPV patients with vitamin D deficiency may improve their symptoms with replacement therapy. More large-scale prospective studies are required to confirm these associations and clarify the exact mechanisms.