Prevalence of vestibulo-ocular reflex dysfunction in people with neurological disorders: a systematic review and meta-analysis

BACKGROUND: Neurological disorders, a leading cause of global disability, often cause debilitating dizziness and imbalance. While subjective symptoms are well-documented, the actual prevalence of vestibulo-ocular reflex (VOR) dysfunction in patients with central nervous system (CNS) damage remains unclear due to inconsistent primary studies. This research aims to determine the prevalence of VOR gain dysfunction, as measured by the video Head Impulse Test (vHIT), across neurological disorders. METHODS: Our systematic review searched MEDLINE, CENTRAL, CINAHL, Scopus, ClinicalTrials.gov, and the WHO ICTRP for original articles from 2009 to September 2025. The JBI Checklist for prevalence studies was used to assess the methodological quality, and descriptive analyses were performed, followed by a meta-analysis of proportions using a random-intercept logistic regression model. RESULTS: We included 48 studies, of which three reported on the same or overlapping samples. Thus, 45 unique studies (1604 participants, 792 females, mean age 56) were described. A meta-analysis of 33 studies (1129 participants) found an overall prevalence of vestibular dysfunction of 48% (95% CI 31-67%). Given the high heterogeneity, we performed subgroup analyses by condition. We found a pooled prevalence of 98% for CANVAS, 73% for ataxia, 44% for Parkinson's disease, 59% for multiple sclerosis, 15% for traumatic brain injury, 5% for multiple system atrophy, and 77% for superficial siderosis. CONCLUSION: Isolated semicircular canal dysfunctions, as documented using vHIT, are prevalent in neurological disorders. Future research must elucidate their etiology and diagnostic potential, utilizing comprehensive vestibular assessments. Eventually, these findings should be translated into improved, evidence-based rehabilitation strategies. PROSPERO REGISTRATION: CRD42024575542.