Alzheimer Disease

Like all types of dementia, Alzheimer's is caused by brain cell death. It is a progressive neurodegenerative disease, which means there is progressive brain cell death that happens over a course of time. The total brain size shrinks with Alzheimer's - the tissue has progressively fewer nerve cells and connections. A neurodegenerative type of dementia, the disease starts mild and gets progressively worse. 

While they cannot be seen or tested in the living brain affected by Alzheimer's disease, postmortem/autopsy will always show tiny inclusions in the nerve tissue, called plaques and tangles:
 

• Plaques are found between the dying cells in the brain - from the build-up of a protein called beta-amyloid (you may hear the term "amyloid plaques").
• The tangles are within the brain neurons - from a disintegration of another protein, called tau. 

The abnormal protein clumps, inclusions, in the brain tissue are always present with the disease, but there could be another underlying process that is actually causing the Alzheimer's - scientists are not yet sure.

This sort of change in brain nerves is also witnessed in other disorders, and researchers want to find out more than just that there are protein abnormalities - they also want to know how these develop so that a cure or prevention might be discovered.  

The most common presentation marking Alzheimer's dementia is where symptoms of memory loss are the most prominent, especially in the area of learning and recalling new information. But the initial presentation can also be one of mainly language problems, in which case the greatest symptom is struggling to find the right words.

If visuospatial deficits are most prominent, meanwhile, these would include inability to recognize objects and faces, to comprehend separate parts of a scene at once (simultanagnosia), and a type of difficulty with reading text (alexia). Finally, the most prominent deficits in "executive dysfunction" would be to do with reasoning, judgment and problem-solving.

Symptoms of Alzheimer's Disease

1. Worsened ability to take in and remember new information, for example:

• "Repetitive questions or conversations
• Misplacing personal belongings
• Forgetting events or appointments
• Getting lost on a familiar route."

2. Impairments to reasoning, complex tasking, exercising judgment:

• "Poor understanding of safety risks
• Inability to manage finances
• Poor decision-making ability
• Inability to plan complex or sequential activities."

3. Impaired visuospatial abilities (but not, for example, due to eye sight problems):

• "Inability to recognize faces or common objects or to find objects in direct view
• Inability to operate simple implements, or orient clothing to the body."

4. Impaired speaking, reading and writing:

• "Difficulty thinking of common words while speaking, hesitations
• Speech, spelling, and writing errors."

5. Changes in personality and behavior, for example:

• Out-of-character mood changes, including agitation; less interest, motivation or initiative; apathy; social withdrawal
• Loss of empathy
• Compulsive, obsessive or socially unacceptable behavior.

 

Stages of Alzheimer's Disease

 The progression of Alzheimer's can be broken down into three basic stages:

• Preclinical (no signs or symptoms yet)
• Mild cognitive impairment
• Dementia.

The Alzheimer's Association has broken this down further, describing seven stages along a continuum of cognitive decline based on symptom severity - from a state of no impairment, through mild and moderate decline, and eventually reaching "very severe decline." 

 It is not usually until stage four that a diagnosis is clear - here it is called mild or early-stage Alzheimer's disease, and "a careful medical interview should be able to detect clear-cut symptoms in several areas." 

Mild Alzheimer;s Disease (early stage)

In the early stages of Alzheimer's, a person may function independently. He or she may still drive, work and be part of social activities. Despite this, the person may feel as if he or she is having memory lapses, such as forgetting familiar words or the location of everyday objects.
Friends, family or neighbors begin to notice difficulties. During a detailed medical interview, doctors may be able to detect problems in memory or concentration. Common difficulties include:

• Problems coming up with the right word or name
• Trouble remembering names when introduced to new people
• Having greater difficulty performing tasks in social or work settings
• Forgetting material that one has just read
• Losing or misplacing a valuable object
• Increasing trouble with planning or organizing

Moderate Alzheimer's Disease (middle stage)

Moderate Alzheimer's is typically the longest stage and can last for many years. As the disease progresses, the person with Alzheimer's will require a greater level of care.
You may notice the person with Alzheimer's confusing words, getting frustrated or angry, or acting in unexpected ways, such as refusing to bathe. Damage to nerve cells in the brain can make it difficult to express thoughts and perform routine tasks.
At this point, symptoms will be noticeable to others and may include:

• Forgetfulness of events or about one's own personal history
• Feeling moody or withdrawn, especially in socially or mentally challenging situations
• Being unable to recall their own address or telephone number or the high school or college from which they graduated
• Confusion about where they are or what day it is
• The need for help choosing proper clothing for the season or the occasion
• Trouble controlling bladder and bowels in some individuals
• Changes in sleep patterns, such as sleeping during the day and becoming restless at night
• An increased risk of wandering and becoming lost
• Personality and behavioral changes, including suspiciousness and delusions or compulsive, repetitive behavior like hand-wringing or tissue shredding

Severe Alzheimer's Disease (late stage)

In the final stage of this disease, individuals lose the ability to respond to their environment, to carry on a conversation and, eventually, to control movement. They may still say words or phrases, but communicating pain becomes difficult. As memory and cognitive skills continue to worsen, personality changes may take place and individuals need extensive help with daily activities.
At this stage, individuals may:

• Require full-time, around-the-clock assistance with daily personal care
• Lose awareness of recent experiences as well as of their surroundings
• Require high levels of assistance with daily activities and personal care
• Experience changes in physical abilities, including the ability to walk, sit and, eventually, swallow
• Have increasing difficulty communicating
• Become vulnerable to infections, especially pneumonia

  

How common is Alzheimer's Disease?

In the US, the most recent census has enabled researchers to give estimates of how many people have Alzheimer's disease. In 2010, some 4.7 million people of 65 years of age and older were living with Alzheimer's disease in the US.

 
The 2013 statistical report from the Alzheimer's Association gives a proportion of the population affected - just over a tenth of people in the over-65 age group have the disease in the US. In the over-85s, the proportion goes up to about a third.
 
  

Information on this page is provided for interest only on a "best efforts" basis and does not 
constitute personal advice. Always discuss medical conditions and related matters with your doctor.

Reference: http://www.medicalnewstoday.com