General characteristics and classification
Dementia belongs to the group of organic brain disorders. The cause is always a disruption of the brain tissue structure and massive neuronal death. Psychological or social factors cannot trigger organic damage.
According to K. Bonhoeffer's concept of exogenous reaction types, the brain has a limited set of standard responses to any injury (trauma, infections, intoxications). The set of dementia symptoms depends not on the nature of the damaging agent, but on the rate of development, severity, and localization of the lesion. Disease dynamics can be of two types:
- Progressive (in tumors, atherosclerosis, and atrophic processes).
- Stable (after trauma or strokes, when partial recovery is possible in the first months).
According to ICD-10, dementia is coded in categories F00-03. It should be remembered that dementia caused by psychoactive substance use belongs to class F1, and epileptic dementia belongs to neurological disorders and category F02.8.
Alzheimer's disease [F00]
This is a common endogenous disease with a gradual onset. The presenile variant (onset at 40–60 years) is most common. Women are affected 3–8 times more often than men.
Pathomorphology: macroscopically, primary cortical atrophy is visible, especially in the parietal and temporal lobes. Microscopically, accumulations of senile (amyloid) plaques and neuronal degeneration in the form of «Alzheimer's tangles» are revealed.
Clinical picture:
- Early stages: formal critical insight into one's condition and the core of the personality are preserved. Apraxia develops fairly quickly — the patient forgets how to dress, use a lock, or operate a stove.
- Cognitive impairments: the ability to calculate is lost (acalculia), speech becomes disjointed with repetition of syllables (logoclonia).
- Behavior: patients are disoriented in a new environment, do not understand the extent of their helplessness, and are prone to wandering and getting lost.
Death usually occurs in a state of profound marasmus from intercurrent diseases (on average 8 years after disease onset).
Senile dementia
The disease starts at 70–80 years and is accompanied by an even grosser total breakdown of the psyche than in Alzheimer's disease. Modern pathological anatomy considers them a single pathology, where the Alzheimer type is an early-onset variant.
Clinical features:
- Eknomia: a specific shift of life into the past. Patients consider themselves children or young people, do not recognize relatives (may call their daughter a sister).
- Dissociation: profound mental breakdown is combined with physical well-being. Patients may retain physical strength.
- Diurnal rhythm: passivity and drowsiness are observed during the day, while fussiness occurs towards evening and at night. Patients rummage through things, tear clothes, and «prepare for a journey».
A sudden decrease in motor activity in such a patient usually indicates the onset of a severe somatic illness, which the patient themselves will not complain about.
Pick's disease and treatment approaches
A special type of dementia is Pick's disease (frontotemporal dementia, category [F02.0]). Unlike Alzheimer's, here the atrophy of the cerebral cortex is localized predominantly in the frontal and temporal gyri.
Treatment of dementia remains a challenging task. There is no etiotropic therapy. Well-known vascular drugs and nootropics (piracetam, vinpocetine) are recognized as ineffective. What works:
- In early stages (replacement therapy): cholinesterase inhibitors (galantamine, rivastigmine, donepezil) and acetylcholine precursors (choline alfoscerate).
- For behavioral correction: in the presence of delusions, dysphoria, or aggression, small doses of antipsychotics (risperidone, quetiapine) are used.
- Other drugs: NMDA receptor blockers (memantine) provide a certain positive effect.
Briefly: answers to topical questions
What stages of Alzheimer's disease are distinguished in clinical practice, and what are their detailed psychopathological criteria?
The clinical picture of the disease distinguishes early (initial) and late stages, as well as the outcome.
- Early stages — the core of the personality and formal critical insight are preserved; apraxia, dysarthria, logoclonia, acalculia, and disorientation in a new environment develop rapidly. In the initial period, unstable persecutory delusions and short-term episodes of clouded consciousness are possible.
- Late stages — focal neurological symptoms join in (oral and grasping automatisms, paresis, increased muscle tone, epileptiform seizures).
- Outcome — gross impairment of mental and physiological functions (marasmus).
To avoid confusing the terms, imagine intellect as a house: oligophrenia is a house that was never finished, and dementia is a sturdy, finished house that was destroyed by an earthquake.
Class and exam questions
Can dementia be completely cured?
No. Dementia is a persistent defect. Treatment with cholinesterase inhibitors can only slow down the process in the early stages, but complete restoration of cognitive functions is impossible.
How does senile dementia differ from Alzheimer's disease?
In modern classifications, they are considered a single pathology. The difference is in onset: Alzheimer's disease starts earlier (40–60 years), while senile dementia starts at 70–80 years, differing by a deeper breakdown of critical insight and «life in the past» (eknomia).
Do nootropics (e.g., piracetam) help in dementia?
No, typical nootropics and vascular agents are ineffective in atrophic processes. Specific drugs are needed: NMDA receptor blockers or cholinesterase inhibitors.
Can severe stress trigger organic dementia?
No. Psychological and social factors do not cause organic brain damage. The cause is always physical, toxic, or atrophic neuronal damage.
What else to study on this topic
- Clinical syndromes of organic dementia: lacunar, total, concentric.
- Oligophrenia: traditional classification (idiocy, imbecility, debility).
- Differences between delayed mental development (DMD) and intellectual disability.
- Syndromes of K. Bonhoeffer's exogenous reaction types.
- Korsakoff's amnestic syndrome and its place in ICD-10.
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Other topics in «Chapter 11. Intellectual Disorders»
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