The 9 types of Alzheimer’s disease (classified and described)

These are the types of Alzheimer's disease explained with their symptoms and effects on the brain.

Alzheimer's disease is a neurodegenerative condition in which the patient suffers from memory problems, in addition to symptoms such as confusion, mood swings, personality changes and aggressive behaviors.

Patients diagnosed with this disease become very dependent on their social environment, since as the disease progresses, their ability to perform simple, everyday tasks fades, as do the memories that shaped their lives.

Although most patients with this dementia show the same symptoms, there are different types of Alzheimer's disease, depending on the severity and other criteria. depending on severity and other criteria that we will explore below.

What is Alzheimer's disease?

Alzheimer's disease is a neurodegenerative condition that brings with it multiple cognitive and behavioral symptoms. The disease usually begins with mild memory loss and confusion, evolving to total memory loss, problems in decision making, and severe difficulties in performing and severe difficulties in performing everyday tasks**.

In addition to these symptoms, there are also changes in the patient's personality along with depressive symptoms, mood swings, social isolation and aggressiveness.

It is believed that some 50 million people worldwide are currently living with Alzheimer's disease.. By the year 2050, the number of cases worldwide is expected to reach 131 million. This disease is one of the first ten causes of death in most developed countries, since the population is aging and this neurodegenerative condition is more common when over 65 years of age. In the particular case of Spain, there is evidence of some 800,000 cases of the disease.

Although age is considered a risk factor for Alzheimer's disease, the symptoms associated with this disease are not simply the result of aging.. Genetics and lifestyle also play a key role in the onset, severity and progression of this neurodegenerative disease, although it is not known exactly to what extent and in certain subtypes of Alzheimer's disease.

Many theories have been proposed from the neurosciences to explain why changes occur at the brain level during the course of Alzheimer's disease. Although there is a variety of explanatory hypotheses, they do agree that there are two distinctive features of this disease: neurofibrillary tangles and senile plaques. there are two distinctive features of this disease: neurofibrillary tangles and senile plaques..

Neurofibrillary tangles are abnormal structures composed of Tau protein, a substance that makes up the cell cytoskeleton.

Senile plaques are structures composed of aggregates of beta-amyloid protein and cause interference in cell communication, eventually leading to the death of neurons.

What types of Alzheimer's disease are there?

There is diversity of opinion in the scientific community not only when it comes to talking about the different types of Alzheimer's that there seem to be, but there is also debate as to whether Alzheimer's can be classified as a dementia on its own or as the cause of one. There is no doubt that it is a brain disease, but there are those who consider that rather than being a type of dementia, it would be the Biological cause of what causes dementia, manifested in cognitive and behavioral symptoms.manifested in cognitive and behavioral symptoms.

Experts who consider Alzheimer's disease as a genuine dementia classify it along with the other types of neurodegenerative diseases in the following categories neurodegenerative diseases in which there is cognitive and behavioral impairment:

• Mild cognitive impairment
• Creutzfeldt-Jakob disease
• Lewy body dementia
• Vascular dementia
• Brain damage associated with alcoholism
• Dementia praecox
• Frontotemporal dementia
• HIV-associated cognitive impairment

According to current knowledge about Alzheimer's disease, it can be classified into different types based on the degree of severity, the type of inflammatory response and the onset or trigger that causes the disease.

According to severity

These are in fact phases through which a person with this neurodegenerative condition usually goes through, the normal range being from mild to severe Alzheimer's disease. Diagnosis is crucial to control the disease, since the earlier a patient with this type of dementia is diagnosed, the more likely it is to be treated effectively and prevent symptoms from progressing rapidly.

Depending on the intensity of the typical symptoms of Alzheimer's disease, we speak of the following types of Alzheimer's disease.

Mild Alzheimer's disease

In mild Alzheimer's disease (Mild Alzheimer's) signs of cognitive impairment begin to appear. The patient has slight problems in doing everyday tasks such as paying bills, doing the washing machine, driving, working...

Because these symptoms are not too noticeable or severe, the patient at this stage of Alzheimer's disease continues to function with some degree of difficulty, but without requiring help from anyone. It will take a little longer to carry out tasks that he or she used to do with agility and speed.

2. Moderate Alzheimer's

In moderate Alzheimer's there is already extensive neuronal damage, which causes the symptoms of the disease to become more intense. The patient suffers more severe episodes of confusion and, due to greater memory loss, begins to require more and more help until he/she becomes dependent. to the point of becoming dependent.

While the patient may remain physically agile, being unable to perform the simplest routine tasks makes it dangerous to leave the patient alone or unsupervised. In addition, the patient may suffer from hallucinations and may suffer from hallucinations and sensory processing failures, and show symptoms of delirium.In addition, he/she may show symptoms of delirium, mood swings and aggressive behavior.

3. Severe Alzheimer's disease

As neurofibrillary plaques and tangles of Tau protein begin to spread throughout the brain, nerve cells begin to die. This results in a shrinking of brain tissue. Patients with severe Alzheimer's often end up bedridden and even lose the ability to speak..

According to the inflammatory response

Alzheimer's disease is categorized into three types depending on the inflammatory response.

Inflammatory Alzheimer's

In addition to exhibiting the cognitive and behavioral symptoms characteristic of the disease, inflammatory Alzheimer's disease has as a distinctive feature a high serum albumin to globulin ratio and a high level of C-reactive protein in response to inflammation, biomarkers characteristic of the disease.These are characteristic biomarkers of this physiological process at the brain level.

2. Non-inflammatory Alzheimer's disease

Non-inflammatory Alzheimer's disease does not present high accumulations of biomarkers associated with inflammation.. However, other typical metabolic alterations associated with this condition may occur, such as plaques and neurofibrillary tangles.

3. Cortical Alzheimer's disease

Cortical Alzheimer's is caused by a deficit in zinc levels in several regions of the brain.. Although there is no inflammatory response associated with this subtype, it causes alterations in the normal functioning of the brain which give rise to the characteristic symptoms of Alzheimer's disease.

Classification according to onset and what triggers the disease.

There are considered to be two types of Alzheimer's disease depending on the age at onset, plus a third type depending on whether it is suspected that there might be heritability among family members for presenting this dementia.

1. Early Alzheimer's disease

We say that Alzheimer's disease is early-onset Alzheimer's disease when it is diagnosed before the age of 65.. These are very rare cases, occurring in only 5 out of every 100 Alzheimer's patients, and the first symptoms may occur as early as 40 or 50 years of age.

Several factors have been considered to explain the onset of early Alzheimer's, although it is believed that the most important is a defect in chromosome 14. People with Down syndrome are prone to this type of Alzheimer's disease.

2. Late-onset Alzheimer's

Most cases of Alzheimer's present the disease after the age of 65, being called late-onset Alzheimer's. This type of Alzheimer's is the most common. This type of Alzheimer's is the most common, accounting for about 95% of cases of people with the disease..

It is not known exactly what is the genetic trigger behind the onset of late-onset Alzheimer's, although it is considered that there would be a combination of genetic and environmental (epigenetic) factors.

Lifestyle and life experiences influence the likelihood of developing Alzheimer's disease.. Risk factors include a stressful lifestyle, drug use, smoking, alcoholism, an unhealthy and unvaried diet, a sedentary lifestyle and being cognitively inactive.

Although it cannot be said that Alzheimer's is a 100% preventable condition, it is true that maintaining a healthy lifestyle, exercising, eating a healthy diet, avoiding the consumption of harmful substances and putting our brain to the test can serve to prevent Alzheimer's and its early onset.

3. Familial Alzheimer's disease

The existence of another subtype of Alzheimer's disease called familial Alzheimer's disease (FAD) has been suggested. This condition would be extremely rareThis condition would be extremely rare, occurring in 1 in 100 patients with this neurodegenerative dementia.

A person can only be diagnosed with FAD if he or she has a specific genotype of the disease, ie, there is a specific gene for Alzheimer's disease in his or her family and he or she has it..

Thanks to this, it is possible to detect whether a family member could have Alzheimer's by means of a genetic analysis to see if he or she has the gene that causes the disease, making it possible to calculate the exact risk of suffering from this dementia.