Slow‐Phase Nystagmus Velocity as a Risk Factor for Lateral Canal BPPV Recurrence

OBJECTIVE: Benign paroxysmal positional vertigo (BPPV) recurrence rates reach 50% within 10 years. While systemic risk factors are known, objective otologic parameters as predictors remain unexplored. This study investigated whether slow-phase velocity (SPV) of positional nystagmus predicts lateral semicircular canal BPPV recurrence. METHODS: Retrospective cohort study of 259 patients with lateral semicircular canal BPPV (2020-2024). SPV was measured via videonystagmography at initial diagnosis. Recurrence was defined as re-presentation with positional nystagmus requiring repeat therapy ≥ 1 month post-resolution. Binomial logistic regression identified independent risk factors. RESULTS: Recurrence group showed significantly higher initial SPV and lower serum calcium. Binomial logistic analysis identified initial SPV and serum calcium as independent predictors. Initial SPV did not correlate with recurrence SPV or timing, suggesting independent otolithic events. CONCLUSIONS: SPV at initial diagnosis is a novel independent risk factor for lateral semicircular canal BPPV recurrence, potentially reflecting otolithic burden. This routinely obtained parameter enables recurrence risk stratification for tailored follow-up and preventive interventions.