LEWY BODY DEMENTIA: SYMPTOMS, CAUSES - ECONOMÍA - 2025

The dementia with Lewy bodies is a degenerative disease, much like the Alzheimer's type dementia, but with specific characteristics that make it a very special dementia syndrome.

In fact, until a few years ago, it did not "exist." In other words, this type of disorder had not been discovered and the people who suffered from it were diagnosed with Alzheimer's disease (AD).

However, in 1980, psychiatrist Kenji Kosaka coined the concept of "Lewy body disease" when witnessing a type of dementia very similar to Alzheimer's-type dementia, but with certain differences.

In fact, this characteristic name (Lewy bodies) refers to the particles that were discovered in the neurons of patients with this type of disorder, which are responsible for producing the degeneration of the brain.

Although Alzheimer's dementia and Lewy body dementia share many characteristics, in Alzheimer's these particles are not present in neurons, so the cause of both types of dementia seems to be different.

However, today many patients with Lewy body dementia remain "misdiagnosed" with Alzheimer's. To try to clarify a bit the properties of Lewy body dementia, below we will discuss all its characteristics and which of them make it different from Alzheimer's dementia.

Symptoms

Cognitive impairment

The main symptom of Lewy body dementia is cognitive impairment, which includes problems with memory, problem solving, planning, abstract thinking, ability to concentrate, language, etc.

Cognitive fluctuations

Likewise, another important characteristic of this disorder is cognitive fluctuations.

This refers to the fact that patients with Lewy body dementia do not always have the same cognitive performance. That is to say: sometimes they seem to have greater mental and intellectual capacities, and sometimes they seem to have a more advanced deterioration.

These variations in their performance are explained by the alterations in the attention and concentration processes that people with this type of dementia present.

In Lewy body dementia, attention and concentration undergo unpredictable changes. There are days or times of the day when the person can be attentive and concentrated, and there are other days when their concentration can be totally off.

In this way, when the person with Lewy body dementia has greater attention and concentration, their cognitive performance increases, and they perform mental activities more effectively, have better functioning, speak more fluently, etc.

However, when attention and concentration are more impaired, their cognitive performance plummets.

Motor signs

Another relevant symptom in Lewy body dementia are motor signs: stiffness, muscle stiffness, tremor, and slowness of movement, which present in a practically identical way as in Parkinson's disease.

Hallucinations

Finally, another main symptom of Lewy body dementia is hallucinations, which are usually visual. Older adults with Lewy body dementia often hear and interpret voices that do not exist, and sometimes see items in a hallucinatory way.

However, in Lewy body dementia other symptoms may also appear, such as:

• REM sleep behavior disorder: this disorder is characterized by living dreams very intensely, which can turn into violent actions and attitudes.
• Significant changes in the autonomic nervous system: regulation of temperature, blood pressure, digestion, dizziness, fainting, sensitivity to heat and cold, sexual dysfunction, urinary incontinence, etc.
• Excessive daytime sleepiness, possible mood disturbances, loss of consciousness, apathy, anxiety, or delusions.

Differences between Alzheimer's disease and Lewy body disease

Despite the multiple similarities, there are also divergent aspects between both diseases, therefore, in many cases it is possible to differentiate a Lewy body dementia from an Alzheimer-type dementia.

The main differences are:

1. In Alzheimer's disease, memory impairment is early and prominent, in Lewy body dementia, memory losses are more variable and generally less important.
2. In Lewy body dementia, visuomotor abilities (such as writing or holding an object) are severely impaired, while in Alzheimer's this deficit is usually not very noticeable.
3. The same happens with visuoconstructive deficits (ability to plan and carry out movements). They are very marked in Lewy body dementia and are less important in Alzheimer's disease.
4. In contrast, Lewy body dementia patients tend to have better verbal memory throughout the course of their disease than Alzheimer's patients.
5. Lewy body dementia has the unique characteristic of presenting fluctuations in cognitive impairment, this does not happen in AD.
6. In Lewy body dementia, hallucinations occur frequently, are very common, and may be present as early as the onset of the disease. In Alzheimer's they are rare and usually appear only in very advanced stages.
7. The same is true of delusions, quite common in Lewy body dementia, and rarely witnessed in Alzheimer's dementia.
8. Other main symptoms of Lewy body dementia are stiffness, tremor, and the typical signs of Parkinson's. Patients with Alzheimer's disease rarely have these symptoms, and if they do, they present them in very advanced stages of the disease.
9. Sometimes insane patients present with hallucinations, a fact that usually requires the use of antipsychotics. When a person with AD takes an antipsychotic drug they usually have a good therapeutic response, when a person with Lewy body dementia takes it they usually have a very bad physical and psychological reaction.
10. In Lewy body dementia, the famous Lewy bodies (cytoplasmic inclusions) are seen in neurons, causing neuronal death and cognitive impairment. In Alzheimer's disease this does not happen.

Statistics

Lewy body dementia is the third leading cause of dementia behind Alzheimer's disease and vascular dementia. In fact, Lewy bodies have been witnessed in the neurons of patients with dementia in approximately 20-30% of autopsies performed.

Studies have found that the prevalence of MCI among people over 65 is 0.7%. The onset of the disease varies between 50 and 90 years of age, and the lifetime prevalence of patients with this type of dementia is usually very short.

In people with MCI, between 6 and 10 years usually elapse between the onset of their disease and their death, thus being one of the dementias with the worst prognosis.

Causes

Lewy body dementia begins when the famous Lewy bodies appear in a person's neurons. Lewy bodies are cytoplasmic inclusions that are made up of different proteins, especially alpha-synuclein.

That is, the brain of patients with Lewy body dementia suffers an alteration in the synthesis of this protein, therefore, it binds to the nucleus of neurons, and thus constitutes Lewy bodies.

Therefore, in the patient's neurons, these bodies begin to appear, which collaborate in the death of the neuron itself and initiate cognitive deterioration.

Likewise, Lewy bodies are distributed by neurons in different brain regions, producing a large number of alterations and causing cognitive deficits in many different areas.

The cause of Lewy body dementia, that is, why Lewy bodies begin to "stick together" in neurons, is currently unknown. However, there seems to be some consensus that there is a genetic component in the development of this disease.

Genetics

Genes such as the apolipoprotein gene or the cytochrome P450 gene appear to be involved in Lewy body dementia.

Likewise, the first seems to be also related to Alzheimer's and the second to Parkinson's, a fact that could explain the characteristic symptoms of Alzheimer's disease and Parkinson's that also occur in Lewy body dementia.

However, these genetic patterns alone would not explain the development of the disorder.

Ambient

Regarding the environment, there are no conclusive studies on what the risk factors for Lewy body dementia could be, however the following seem to be related:

1. Age: as in most dementia syndromes, the older you are, the more likely you are to develop MCI.
2. Cholesterol: although there are no studies that clearly demonstrate it, having cholesterol could be a risk factor.
3. Alcohol: high alcohol consumption could increase the risk of developing MCI, although moderate consumption could reduce it.
4. Diabetes: in the same way, although there is no etiological evidence, there are authors who defend that diabetes may be a contributing factor in the development of MCI.
5. Mild cognitive impairment: This disorder greatly increases the risk of dementia as you age. From 65 years of age the risk can increase up to 40%.

How can it be treated?

Lewy body dementia has a wide range of symptoms, which is why it is important to perform different therapeutic interventions.

With regard to cognitive impairment, it is important to carry out cognitive stimulation activities to try to slow down the progress of the disease as much as possible.

Working on the patient's deficits such as attention, concentration, memory, language or visual construction, can favor the maintenance of their cognitive abilities.

Regarding hallucinations, these should only be treated when they produce anxiety or agitation in the patient. Conventional antipsychotics such as haloperidol are contraindicated due to their strong side effects.

In those cases where it is essential to treat hallucinations, atypical antipsychotics such as risperidone can be administered.

Finally, parkinsonian symptoms are also often difficult to treat as antiparkinson drugs are often ineffective and cause many side effects in patients with MCI.

When the tremor or rigidity is very high, small doses of L-dopa can be administered.

References

1. Del Ser Quijano, T. (2001). Lewy body dementia. In A. Robles and JM Martinez, Alzheimer 2001: theory and practice (pp. 147-157). Madrid: Medical Classroom.
2. Demey, I, Allegri, R (2008). Dementia in Parkinson's disease and Lewy body dementia. Revista Neurológica Argentina; 33: 3-21.
3. Kauffer, DI (2003). Dementia and Lewy bodies. Rev Neurol; 37 (2): 127-130.
4. Martín, M. (2004). Antipsychotic drugs in the treatment of psychiatric symptoms of dementias. Psychiatric Information, 176.
5. McKeith I, Del-Ser T, Spano PF, et al (2000). Efficacy of rivastigmine in dementia with Lewy bodies: a randomized, double-blind, placebo-controlled international study. Lancet; 356: 2031-36.
6. McKeith IG, Ballard CG, Perry RH, et al (2000). Prospective validation of consensus criteria for the diagnosis of dementia with Lewy bodies. Neurology; 54: 1050–58.
7. Rahkonen T, Eloniemi-Sulkava U, Rissanen S, Vatanen A, Viramo P, Sulkava R (2003). Dementia with Lewy bodies according to the consensus criteria in a general population aged 75 years or older. J Neurol Neurosurg Psychiatry; 74: 720–24.
8. Networks for science (May 22, 2011) Cap 96: the scourge of Alzheimer's.. Retrieved from
9. Stevens T, Livingston G, Kitchen G, Manela M, Walker Z, Katona C (2002). Islington study of dementia subtypes in the community. Br J Psychiatry; 180: 270–76.