Alzheimer’s Disease: Definition, Symptoms, Causes, And Diagnosis

Alzheimer’s disease is one of the brains characterized by the slowly progressive deterioration of the disease memory and changes in reasoning, language, planning, and perception. Many scientists believe that this disease results from an increase in the production or accumulation of a specific protein (beta-amyloid protein) in the brain that leads to the death of nerve cells.

The probability of having Alzheimer’s disease increases substantially after the age of 70 and can affect around 50% of people over 85. However, it is not a normal part of aging, and it is not something that inevitably occurs in adult life. For example, many people live to be 100 years old and never develop such a disease.

Symptoms of Alzheimer’s disease

Alzheimer's disease

At first, forgetfulness or mild confusion may be the only symptoms of the disease, but over time, it robs you of more of your memory, especially recent memories; the speed at which the symptoms get worse varies from person to person.

The early symptoms of Alzheimer’s disease vary from person to person. For many, declines in non-memory aspects of cognition, such as word search, visual/spatial problems, and poor reasoning or judgment, can signal the early stages of Alzheimer’s disease.

Researchers are studying biomarkers – biological signs of disease found in brain imaging, cerebrospinal fluid, and blood – to see if they can detect early changes in the brains of people with mild cognitive impairment and in cognitively ordinary people who may be at increased risk. To develop Alzheimer’s.

Studies indicate that such early detection may be possible, but more research is needed before these techniques can be used to diagnose the disease in everyday medical practice.

If you have Alzheimer’s, you may be the first to realize that he has unusual difficulties remembering things and organizing his thoughts, or you may not recognize that something is wrong, even when the changes are noticeable to his family members, close friends, or co-workers.

Brain changes associated with Alzheimer’s disease led to increasing problems with:


Everyone has occasional memory lapses, it is customary to lose track of where you put your keys or forget the name of an acquaintance, but the memory loss associated with the disease persists and worsens, affecting your ability to function at work and home. Home.

People with Alzheimer’s can:

  • Repeating the statements and questions repeatedly, without realizing that they already asked the question.
  • Forgetting conversations, appointments, or events and don’t remember them later.
  • You routinely lose possessions, often placing them in illogical places.
  • Get lost in familiar places.
  • Finally, you forget the names of family members and everyday objects.
  • You have trouble finding the correct words, identifying objects, expressing thoughts, or participating in conversations.

Thinking and reasoning

Alzheimer’s disease causes difficulty concentrating and thinking, especially abstract concepts like numbers. Multitasking is complicated, and it can be challenging to manage finances, track checks, and pay bills on time. These difficulties can advance the inability to recognize and deal with numbers.

Make judgments and decisions.

Responding effectively to everyday problems, such as burning food on the stove or unexpected driving situations, becomes increasingly challenging.

Planning and carrying out family tasks.

Once routine activities that require sequential steps, such as planning and preparing a meal or playing your favorite game, become a struggle as the disease progresses. Finally, people with advanced Alzheimer’s may forget how to perform basic tasks, such as bathing and dressing.

Changes in personality and behavior

The brain changes in Alzheimer’s disease can affect how you act and how you feel. People can experience:

  • Depression
  • Apathy
  • Social retreat
  • Humor changes
  • Mistrust in others
  • Irritability and aggressiveness
  • Changes in sleeping habits.
  • Wandering
  • Loss of inhibitions
  • Delusions, such as believing that something has been stolen.

Many skills are not lost until the disease has advanced. These include reading, dancing, singing, enjoying old music, participating in crafts and hobbies, telling stories, and remembering.

This is because information, skills, and habits learned early in life are among the last abilities to be lost as the disease progresses; the part of the brain that stores this information tends to be affected later in the condition. Capitalizing on these skills can promote success and maintain quality of life even in the intermediate phase of the disease.

Causes of Alzheimer’s disease

Scientists believe that for most people, the disease is caused by a combination of genetic, lifestyle, and environmental factors that affect the brain over time.

Less than 5 percent of the time, the disease is caused by specific genetic changes that virtually guarantee that a person will develop the disease.

Although the causes of Alzheimer’s disease are not yet fully understood, its effect on the brain is transparent. The disease damages and kills brain cells. A brain affected by Alzheimer’s disease has far fewer cells and far fewer connections between surviving cells than a healthy brain.

As more and more brain cells die, the disease causes significant brain shrinkage. When doctors examine brain tissue under a microscope, they see two types of abnormalities that are considered hallmarks of the disease:

  • Plaques: These clumps of a protein called beta-amyloid can damage and destroy brain cells, including interfering with cell-to-cell communication. Although the actual cause of Alzheimer’s brain cell death is unknown, the beta-amyloid collection on the outside of brain cells is the prime suspect.
  • Tangles: Brain cells depend on an internal support and transport system to transport nutrients and other essential materials along their long stretches. This system requires the structure and normal and consistent functioning of a tau protein.

In Alzheimer’s disease, the tau protein threads twist into abnormal tangles within brain cells, leading to the failure of the transport system. This failure is also strongly implicated in the decline and death of brain cells.

Risk factors for Alzheimer’s disease


Increasing age is the most significant known risk factor for Alzheimer’s, as it is not part of normal aging, but your risk increases much after you turn 65. The dementia rate multiplies every decade after the age of 60.

People with rare genetic changes related to early-onset Alzheimer’s begin to experience symptoms as early as their 30s.

Family history and genetics

Your risk of developing Alzheimer’s appears to be somewhat higher if a first-degree relative, your father or brother, has the disease. Scientists have identified and discovered rare changes (mutations) in three genes that virtually guarantee that a person inherits them can develop Alzheimer’s. But these mutations account for less than 5% of the disease.

Most of the genetic mechanisms of Alzheimer’s among families remain largely unexplained. The most substantial risk gene researchers have found so far is apolipoprotein e4 (APoE4), although not everyone with this gene develops Alzheimer’s disease. Other risk genes have been identified but not conclusively confirmed.

Down syndrome

Many people with this syndrome develop Alzheimer’s disease. The signs and symptoms tend to appear more than anything between 10 and 20 years earlier in people with Down syndrome than in the general population. A gene on the extra chromosome that causes the syndrome significantly increases the risk of Alzheimer’s disease.


Women appear to be more likely than men to develop Alzheimer’s disease because they live longer.

Mild cognitive impairment

People with mild cognitive impairment may have memory problems or other symptoms due to the same impairment, which are worse depending on their age, but not severe enough that the result is dementia.

People with this defect are at increased risk but are not confident of later developing dementia. Taking steps to establish a healthy life and obvious strategies to compensate for forgetfulness at this stage can help delay or better prevent the progression to dementia.


People who have had a severe head injury appear to be at increased risk for Alzheimer’s disease.

Lifestyle and heart health

No lifestyle factor has been definitively shown to reduce the risk of Alzheimer’s disease. However, some evidence suggests that the same factors that put you at risk for heart disease can also increase your chances of developing Alzheimer’s. Examples include:

  • Lack of exercise
  • Obesity
  • Smoking or being exposed to another person who smokes.
  • High blood pressure
  • High blood cholesterol
  • Poorly controlled type 2 diabetes
  • A diet that does not include fruits and vegetables.

These risk factors are also linked to vascular dementia, a type of dementia caused by damaged blood vessels in the brain. Working with your health care team on a plan to control these factors will help protect your heart and may also help reduce the risk of Alzheimer’s disease and vascular dementia.

Lifelong learning and social commitment

Studies have found an association between lifetime participation in mentally and socially stimulating activities and a reduced risk of Alzheimer’s disease. Low levels of education, less than secondary education, appear to be a risk factor for Alzheimer’s disease.

Complications of Alzheimer’s disease

Memory and language loss, impaired judgment, and other cognitive changes caused by Alzheimer’s can complicate treatment for other health conditions. A person who has Alzheimer’s may not be able to:

  • Report pain, for example, from a dental problem
  • Report symptoms of another illness
  • Follow a prescribed treatment plan.
  • Observe or describe the side effects that medications cause you.

As the disease progresses to its later stages, brain changes will affect physical functions, balance, and bowel and bladder control. These effects can increase vulnerability to additional health problems, such as:

  • I was inhaling food or liquids into the lungs (aspiration).
  • Pneumonia and other infections.
  • Falls
  • Fractures
  • Pressure ulcers.
  • Malnutrition or dehydration.

Diagnosis of Alzheimer’s disease

Doctors use various methods and tools to help determine whether a person with memory problems has “possible Alzheimer’s dementia” (dementia may be due to another cause) or “probable Alzheimer’s dementia” (no other reason can be found for dementia).

To diagnose this disease, doctors can:

  • Ask the person and a family member or friend about general health, past medical problems, ability to carry out daily activities, and changes in both behavior and personality.
  • Conduct tests of memory, attention, problem-solving, counting, and language.
  • Perform standard medical tests, such as blood and urine tests, to identify other possible causes of the problem.
  • Perform brain scans, such as CT scans, MRI, or positron emission tomography to rule out other possible causes of symptoms.

These tests can be repeated to give doctors information about how the person’s memory and other cognitive functions change over time. Alzheimer’s disease can be definitively diagnosed only after death by linking clinical measurements with an examination of brain tissue at an autopsy.

People with memory and thinking problems should talk to their doctor to find out if their symptoms are due to Alzheimer’s disease or another cause, such as stroke, tumor, Parkinson’s disease, sleep disturbances, medication side effects, an infection, dementia, some of these conditions may be treatable and possibly reversible.

If the diagnosis is Alzheimer’s, starting treatment early in the disease process can help preserve daily functioning for a time. However, the underlying disease process cannot be stopped or reversed. An early diagnosis also helps families plan for the future. They can deal with financial and legal matters, address potential safety issues, learn about living arrangements, and develop support networks.

In addition, an early diagnosis gives people more significant opportunities to participate in clinical trials that are testing possible new treatments for Alzheimer’s disease or other research studies.

Prevention of Alzheimer’s disease

There is no proven way to prevent Alzheimer’s disease; research into prevention strategies is ongoing. The most substantial evidence so far suggests that you may be able to lower your risk by reducing your risk of heart disease.

Many factors that increase the risk of heart disease can also increase the risk of Alzheimer’s and vascular dementia. The essential factors exposed include high blood pressure, high blood cholesterol, excess weight, and diabetes.

The Mediterranean diet, a form of diet that emphasizes fresh produce, healthy oils, and foods low in saturated fat, can reduce the risk of death from cardiovascular disease and stroke. This diet has also been associated with a reduced risk of Alzheimer’s disease.

Staying active physically, mentally, and socially can make your life more pleasant and help reduce the risk of Alzheimer’s. Take care of your health and if you see that something is not right in terms of your health, visit your doctor.

Georgia Tarrant
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Hello, how are you? My name is Georgia Tarrant, and I am a clinical psychologist. In everyday life, professional obligations seem to predominate over our personal life. It's as if work takes up more and more of the time we'd love to devote to our love life, our family, or even a moment of leisure.