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Causes of cognitive impairment
Last reviewed: 06.07.2025
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Causes of cognitive impairment
Dementia is a polyetiological syndrome that develops with various diseases of the brain. There are several dozen nosological forms within which dementia syndrome can develop. The most common of them are Alzheimer's disease, dementia with Lewy bodies, cerebrovascular insufficiency, frontotemporal degeneration, diseases with predominant damage to the subcortical basal ganglia ("subcortical dementia"). The specified nosological forms are responsible for at least 80% of dementia in old age.
The main causes of dementia are as follows.
- Neurodegenerative diseases:
- Alzheimer's disease;
- Lewy body disease;
- frontotemporal degeneration;
- Parkinson's disease;
- progressive supranuclear palsy;
- Huntington's disease.
- Cerebrovascular diseases:
- consequences of a "strategic" infarction;
- multi-infarct dementia;
- subcortical vascular dementia;
- hemorrhagic dementia;
- mixed options.
- Mixed (vascular-degenerative) brain lesions.
- Dysmetabolic encephalopathies:
- alcoholism;
- somatogenic disorders:
- hypoxic encephalopathy;
- hepatic encephalopathy;
- renal encephalopathy;
- hypoglycemic encephalopathy;
- hypothyroidism;
- deficiency states (deficiency of vitamins B 1, B 12, folic acid, proteins);
- intoxication with metal salts (aluminum, zinc, copper);
- intoxication with drugs (anticholinergics, barbiturates, benzodiazepines, neuroleptics, lithium salts, etc.);
- hepatolenticular degeneration.
- Neuroinfections and demyelinating diseases:
- HIV-associated encephalopathy;
- spongiform encephalitis (Creutzfeldt-Jakob disease);
- progressive panencephalitis (measles, van Bogaert, rubella);
- consequences of acute and subacute meningoencephalitis;
- progressive paralysis;
- multiple sclerosis;
- progressive multifocal leukoencephalopathy.
- Traumatic brain injury.
- Brain tumor.
- Liquorodynamic disorders:
- normotensive (aresorptive) hydrocephalus.
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