Short-Term Memory Loss in Vestibular Patients can Arise Independently of Psychiatric Impairment, Fatigue and Sleeplessness (P2.159)

Objective: To quantify the nature and extent of neuropsychiatric impairment in patients with vestibular disorder. Background: Beyond the acute effects of vertigo and unsteadiness, disease or injury to the human vestibular system is commonly accompanied by subjective reports of memory loss and problems concentrating. The comorbid presence of psychiatric illness, fatigue and difficulty sleeping, coupled with the lack of comprehensive, validated neuropsychological assessment, has left questions unanswered about the origin and nature of these underlying memory and attentional impairments. Design/Methods: 100 patients diagnosed with primary vestibular disorder (mostly vestibular migraine) at their initial neuro-otology appointment completed validated neuropsychological assessments of depression, anxiety, depersonalisation, fatigue, sleep, memory and attention. Vestibular pathology was characterised using a range of behavioural and physiological assessments. Statistical analyses first calculated the prevalence of cognitive and other comorbid impairments. Structural equation models then tested whether vestibular function exerted a direct influence on cognition, or influenced performance indirectly via psychiatric, fatigue/sleep mechanisms. All models were adjusted for age. Results: Consistent with the idea of a ‘vestibular cognitive affective’ syndrome, most patients presented with a combination of anxiety, depression, sleep disturbance, fatigue, working memory impairments and problems sustaining attention. Importantly, balance function, assessed via balance platform (a measure of unassisted posture), influenced visuospatial memory performance independently of any age, psychiatric or fatigue/sleep-related effects. Conclusions: The present findings identify new clusters of impairment and highlight a direct effect of vestibular dysfunction on short-term visuospatial memory. We suggest that the most likely anatomical route is via the vestibulo-thalamocortical pathway which passes vestibular signals to several areas associated with working memory and visuospatial processing including the hippocampus, parietal cortex, frontal cortex and basal ganglia. We suggest that patients presenting to their GPs with balance and other neuropsychiatric symptoms should be promptly referred for a neurootological opinion given the likelihood of an underlying vestibular disorder. Disclosure: Dr. Surenthiran has nothing to disclose. Dr. Smith has nothing to disclose. Dr. Wilkinson has nothing to disclose. Dr. Bicknell has nothing to disclose. Dr. Bodani has nothing to disclose.