Lewy body dementia: main causes

Studies of families with the dementia give reason to argue about the hereditary nature of the development of dementia with Lewy bodies. Numerous Lewy bodies are found in patients with dementia in cortical and subcortical neurons. Lewy bodies damage brain cells and break connections between them.

Numerous amyloid plaques are identified, like in Alzheimer’s disease. The formation of Lewy bodies is associated with the action of the apolipoprotein E of the 19th chromosome, which is also involved in the development of late-onset Alzheimer’s disease.

Lewy body dementia has both clinical and morphological similarities to Parkinson’s disease. As the Parkinson’s disease, Lewy body dementia is characterized by the appearance of a special neurological syndrome (tremor, muscle rigidity, postural instability).

Symptoms of dementia with Lewy bodies

Dementia is characterized by the emergence of progressive cognitive disorders in the first year of the disease. For dementia with Lewy bodies, Parkinson’s syndrome is typical, with minor memory impairments (unlike Alzheimer’s disease). The clinical picture of Parkinson’s syndrome includes:

• muscle rigidity (increased muscle tone, uniform muscle resistance);
• impaired movement (difficulty walking, difficulty in maintaining balance, falling);
• tremor (not as hard as in Parkinson’s disease).

There are repeated hallucinations, strong fluctuations in attention and intelligence. The patient has periods of clarity of mind, which are replaced by clouding of consciousness. The periods of turbidity can last for hours or even several days, after that everything returns to be normal. During such periods, the perception of reality is distorted, speech is disturbed or slowed down, the patient may not respond to others, he or she has a “missing” look.

The patient who suffers from a dementia with Lewy bodies, is difficult to concentrate, his or her attention is disturbed. The person may have significant difficulties in performing long-term work that requires mental stress. The patient quickly gets tired, gets distracted, the attention switches constantly.

The patient gets a sleep disorder with nightmares. Patients may shout and talk in a sleep, they also can walk or actively gesticulate.

Patients have pronounced detailed repetitive visual hallucinations (people, animals, various scenes). In the early stages of the development of dementia with Lewy bodies, the patient retains critical thinking during hallucinations, so he or she can distinguish fiction from the real world. Further the criticism disappears completely.

Other signs of the development of dementia with Lewy bodies include:

• severe sensitivity to neuroleptics;
• depression;
• frequent fainting.