Chronic vestibular migraine (CVM) and cerebrovascular insufficiency are recognized contributors to cognitive impairment. Vestibular dysfunction affects spatial orientation and balance, while compromised cerebral perfusion impacts neuronal health. This study explores the combined pathological effects of these conditions and their role in cognitive decline and dementia. To evaluate the association between chronic vestibular migraine, cerebrovascular insufficiency, and their potential role in accelerating cognitive decline and the onset of dementia. A patient was evaluated from the ages of 48 to 74 years, initially diagnosed with chronic vestibular migraine and later developing cerebrovascular insufficiency. Cognitive function was assessed using the Mini-Mental State Examination (MMSE) over a 5-year follow-up. Neuroimaging, including MRI and CT angiography, was employed to assess cerebral perfusion and white matter changes. The incidence of dementia was evaluated based on the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) criteria. The patient with coexisting CVM and cerebrovascular insufficiency demonstrated rapid cognitive decline, with MMSE scores decreasing by an average of 5 points over the follow-up period. Neuroimaging revealed microvascular ischemic changes and white matter lesions. Frequent vestibular migraines were associated with the progression to dementia over years of regular assessment and follow-up. Chronic vestibular migraine and cerebrovascular insufficiency are significantly associated with accelerated cognitive decline and an increased risk of dementia. The presence of white matter lesions and ischemic changes appears to exacerbate neurodegeneration. Early diagnosis and management of vestibular dysfunction and cerebrovascular risk factors may help mitigate cognitive decline and reduce the incidence of dementia in affected patients.