BackgroundBenign paroxysmal positional vertigo (BPPV) is the most common peripheral vestibular disorder, and its prevalence is substantial. While primary BPPV has been well studied, the understanding of secondary BPPV is still limited.ObjectiveTo investigate the prevalence and clinical characteristics of secondary BPPV in a national multicenter retrospective analysis.MethodsThe study involved a retrospective analysis of medical records from 17 institutions across South Korea, between January and June 2022. We evaluated clinical features, presumed etiologies, involvement of semicircular canals, response to canalith repositioning procedures (CRPs), presence of residual dizziness, recurrence, and results of auditory and vestibular function tests for both primary and secondary BPPV cases.ResultsOf the total 1363 BPPV cases, 14.5% (198 patients) were categorized as secondary BPPV. The most prevalent etiology for secondary BPPV was head trauma. Secondary BPPV was associated with a higher prevalence of comorbidities including diabetes and inner ear diseases. Patients with secondary BPPV demonstrated more frequent involvement of multiple semicircular canals, necessitated a greater number of CRPs for resolution, and experienced a higher incidence of residual dizziness compared to primary BPPV cases. Furthermore, secondary BPPV patients exhibited more frequent abnormalities in auditory and vestibular function tests.ConclusionsSecondary BPPV accounts for a significant proportion of BPPV cases, with distinct clinical characteristics compared to primary BPPV.