Serum otolin-1 level is specific to benign paroxysmal positional vertigo

Abstract

Objectives: When we see patients with a history of positional vertigo (PV), many patients are diagnosed with benign paroxysmal PV (BPPV) by performing a typical history and nystagmus during a positioning maneuver. Recent studies reported that Otolin-1 can be detected in serum and that its levels significantly increase with age and BPPV. Herein, we tried to study the relationship between serum otolin-1 level and the other clinical aspects in patients with PV.Methods: We measured the serum levels of otolin-1 in 117 BPPV patients (82 females; age range, 43–92 years; mean age±standard deviation [SD], 68.5±10.5 years), referred to as the BPPV group; and nine patients (seven females; age range, 61–79 years; mean age±SD, 66.9±5.9 years) with PV not compatible with BPPV, referred to as another PV group. All the BPPV patients were treated with an appropriate canal repositioning maneuver followed by blood sampling within 1 week. Results: The serum levels of otolin-1 were higher in the BPPV group than in another PV group (mean±SD, 350.1±319.1 pg/mL vs. 183.6±134.1 pg/mL, respectively; p=0.037). However, there were no differences in both laboratory findings (serum vitamin D, C-telopeptide of type collagen, and bone mineral density) and clinical findings (age, sex, vertigo duration, ear disease, ear symptom, migraine, motion sickness, trauma, and previous BPPV) between these two groups. Conclusions: Serum otolin-1 level could help predict the current existence of BPPV in patients with PV. However, further validation studies are needed.