Vascular dementia is the second most common cause of dementia after Alzheimer’s. It accounts for up to 20 percent of all dementias. It can be developed following vascular catastrophes (hemorrhagic or ischemic strokes) or against the background of chronic brain circulation failure.
In case of hemorrhagic (vascular rupture) and ischemic strokes (terminated or difficult blood supply in a certain area of the brain), brain cells in this area are destructed or damaged. The patient develops focal symptoms which depend on the localization of the affected area (spastic paralyses, aphasia, agnosia, apraxia, etc.). The clinical picture of post-insult dementia depends on the affection level of the brain area which is supplied with blood through the affected vessel and also on medical aid timely and properly rendered during a vascular catastrophe.
In chronic circulatory failure of the brain, dementia is usually developed in elderly patients and has a more homogenous clinical picture.
The most common causes of dementia of vascular origin are disorders resulting in chronic cerebrovascular insufficiency, hypertension and cerebral atherosclerosis. Moreover, affection of vessels in diabetes mellitus (diabetic angiopathy) and systemic vasculitis along with congenital dysmorphology of cerebral vessels can lead to chronic hypoxia (lack of oxygen) of cerebral cells.
The most significant risk factors of vascular dementia:
- higher level of blood lipids and cholesterol;
- cardiac diseases (ischemic heart disease, arrhythmia, cardiac valve defect);
- tendency towards thrombus formation;
- systemic vasculitis (vascular diseases);
concentration problems, rapid fatiguability, slow intellectual activity leading to difficult of planning, data analysis and making conclusions are typical of initial stages of vascular dementia. Unlike in dementia of the Alzheimer’s type, memory impairment is mainly manifested as difficulties with reproduction of perceived and accumulated data. It’s easier for the patient to recollect something left behind when suggestive questions are asked or to select a correct answer out of several suggested ones as compared to patients with Alzheimer’s disease.
Vascular dementia is accompanied by emotional disturbances such as low mood through to depression developed in 25–30 % of patients and pronounced emotional instability manifested through crying for no reason and fast transformation of tears into laughter.
Prognosis of vascular dementia resulting from chronic brain circulatory deficiency is mainly determined by successful treatment of underlying disease (hypertension, atherosclerosis, diabetes mellitus, etc.) and timely initiated therapy with anti-dementia agents (NMDA receptor antagonists and cholinesterase inhibitors).
N. M. Zalutskaya
Doctor of Medical Sciences, St. Petersburg Psychoneurological Research Institute bearing today the name of V. M. Bekhterev