Cognitive disorders of vascular origin
Vascular dementia is defined as an impairment of cognitive functions caused by vascular lesions within the brain. Brain vascular lesions can be ischemic (cerebral infarct related to an arterial occlusion) or hemorrhagic and can be multiple or unique and strategically situated to badly impact cognitive functions. About one in ten patients has dementia before the first brain stroke, one in ten develops dementia after the first stoke and more than one in three patients develop dementia after a recurrent stroke.
Vascular dementia is characterized by memory losses less severe that in the AD, a loss of initiative, some difficulties to organize, to plan and a slowing down of cognition. Behavioral disorders are frequent with increased irritability, impulsivity and emotional lability.
Cognitive disorders onset can happen after a brain stroke and present a progression in spurs. There is also more insidious and progressive forms of vascular dementia, making detection and diagnostic more complex.
Some vascular dementias are found in young subjects, especially when a genetic disease is involved. The CASADIL (for Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy) is related to a mutation of the NOTCH 3 gene and is characterized by small and repetitive brain strokes, with migraine headaches and psychiatric disorders. Some MRI image features are very characteristic of the disease and the diagnosis can be confirmed by genetic analyses. Other very rare forms of genetic mutations can induce brain vascular strocke in young adults (Fabry disease, Marfan syndrome, Homocystinurea…)
A vascular dementia diagnosis is made considering the patient’s history of vascular and metabolic risk factors (arterial blood high pressure, diabetes, hypercholesterolemia), the clinical observation of neurological signs and the observation of vascular lesions on brain images. Presence of such lesions induces a complementary cardiac and vascular check-up.
Association of vascular brain lesions with Alzheimer disease like brain lesions is possible and denominated mixed dementia. However the real burden of those two types of lesion on cognitive impairment is difficult to evaluate. Mixed form of dementia is frequently observed in elderly patients.
There is no specific treatment for dementia of vascular origin. Current clinical care consists on controlling strictly the cardio-vascular risk factors (high blood pressure, cholesterol blood level, diabetes).
Mood and behavioral disorders can be also specifically treated.
The impact on the family for a patient with vascular dementia is often more severe than the impact for a patient in early phase of Alzheimer disease.
Patient apathy and lack of initiative impose regular incitations from the close relatives, to perform daily life tasks. Behavioral disorders can also induce tension within the family and refusal of care from the patient. In those cases, some support measures, use of respite platforms and provision of home help services are essential for the wellbeing of the patient and close relatives.
