The number of global Alzheimer’s disease cases is currently at 55 million. It’s the 7th leading cause of death across the globe. Without medical breakthroughs, we’ll see an estimated 10 million new cases yearly. That’s one person in the world developing Alzheimer’s every 3.2 seconds. (W.H.O., 2022). In healthy aging, the brain normally shrinks to some extent but, surprisingly, does not lose a significant amount of neurons. However, with Alzheimer’s disease, there is extensive damage because a large number of neurons cease working, lose their connections to other neurons, and eventually die. The communication, metabolism, and repair processes that are essential to neurons and their networks are interfered with by Alzheimer’s disease.
Alzheimer’s disease is a neuro degenerative disease that results in the death of brain cells and brain shrinkage. It is the most frequent cause of dementia, which is characterized by a steady deterioration in mental, behavioral, and social abilities and impairs a person’s capacity for independent functioning. Alzheimer’s disease often starts by destroying neurons and the connections between them in the entorhinal cortex and hippocampus, two regions of the brain involved in memory. Later, it has an impact on the parts of the cerebral cortex that control language, thought, and social interaction. Eventually, the brain’s many other regions suffer harm. A person with Alzheimer’s disease gradually loses the ability to live and work independently over time.
A person with Alzheimer’s disease experiences numerous molecular and cellular alterations in their brain. After death, these modifications can be seen in the brain’s tissue under a microscope. Researches are ongoing to identify the alterations that may lead to Alzheimer’s and those that may be a complication.
CHARACTERISTICS OF ALZHEIMER DISEASE
- AMYLOID PLAQUE
Numerous molecular variations of the beta-amyloid protein, which is linked to Alzheimer’s disease, build up between neurons. It is created when a bigger protein known as amyloid precursor protein breaks down. Beta-amyloid 42 is one type that is thought to be particularly hazardous. This naturally occurring protein congregates abnormally in the Alzheimer’s brain to produce plaques that build up between neurons and impair cell function. To learn more about how and when the various kinds of beta-amyloid affect Alzheimer’s, research is still being done.
- TANGLES IN THE NEURONS
Tau protein aberrant accumulations called neurofibrillary tangles build up inside neurons. Microtubules, which assist transport chemicals and nutrients from the cell body to the axon and dendrites, support healthy neurons in part on the inside. Tau typically attaches to and stabilizes microtubules in healthy neurons. However, abnormal chemical changes in Alzheimer’s disease lead tau to separate from microtubules and adhere to other tau molecules, generating threads that eventually connect to create tangles inside neurons. These tangles interfere with the transport mechanism of the cell, impairing synaptic transmission between neurons.
New research reveals that aberrant tau and beta-amyloid proteins, along with a number of other factors, may play a complex role in the development of the brain abnormalities associated with Alzheimer’s disease. It appears that specific memory-related brain areas are where aberrant tau builds up. Plaques of beta-amyloid form between neurons. When the amount of beta-amyloid hits a critical degree, tau spreads quickly throughout the brain.
- PERSISTENT INFLAMMATION
According to research, the accumulation of glial cells—which are often intended to help maintain the brain clear of debris—could be the root cause of chronic inflammation. In a healthy brain, microglia, one type of glial cell, ingest and eliminate waste and toxins. Beta-amyloid plaques and other protein accumulations, including waste and debris, are not removed by microglia in Alzheimer’s disease. Why microglia are unable to carry out this crucial task in Alzheimer’s disease is now under investigation. A gene termed TREM2 is a subject of research. TREM2 normally instructs the microglia cells to remove beta-amyloid plaques from the brain and aids in reducing inflammation there. Plaques accumulate between neurons in the brains of persons with this gene disorder. To assist in removing the accumulation of plaques and other cellular waste left behind, astrocytes—another kind of glial cell—are signaled. Although they gather around the neurons, these astrocytes and microglia are unable to carry out their debris-clearing duties. They also expel substances that prolong chronic inflammation and further harm the neurons they are supposed to shield.
- VASCULATURE TO ALZHEIMER’S DISEASE
Rarely do people with dementia just exhibit brain abnormalities associated with Alzheimer’s disease. Vascular disorders, or difficulties affecting blood vessels, may potentially be at work. Examples include beta-amyloid deposits in brain arteries, atherosclerosis (hardening of the arteries), and mini-strokes. Vascular issues can result in decreased oxygen and blood flow to the brain as well as a rupturing of the blood-brain barrier, which typically shields the brain from hazardous substances while allowing in glucose and other essential components.
A dysfunctional blood-brain barrier in an Alzheimer’s patient inhibits glucose from getting to the brain and hinders the removal of harmful beta-amyloid and tau proteins. Inflammation follows, which worsens the vascular issues in the brain. Researchers are looking for therapies to break up this complex and harmful cycle because it appears that vascular issues in the brain are both a cause and a consequence of Alzheimer’s disease.
- CELL DEATH AND LOSS OF NEURONAL CONNECTIONS
As neurons are damaged and die throughout the brain in Alzheimer’s disease, connections between networks of neurons may deteriorate and many brain regions start to shrink. This process, known as brain atrophy, is widespread by the time Alzheimer’s is in its terminal stages and results in a considerable reduction of brain volume.
STAGES OF ALZHEIMER DISEASE
Stage 1: Normal Outward Behavior
Alzheimer’s disease usually starts silently, with brain changes that begin years before anyone notices a problem. When your loved one is in this early phase, they won’t have any symptoms that you can spot. Only a PET scan, an imaging test that shows how the brain is working, can reveal whether they have Alzheimer’s. As they move into the next six stages, your friend or relative with Alzheimer’s will see more and more changes in their thinking and reasoning.
Stage 2: Very Mild Changes
You still might not notice anything amiss in your loved one’s behavior, but they may be picking up on small differences, things that even a doctor doesn’t catch. This could include forgetting words or misplacing objects. At this stage, subtle symptoms of Alzheimer’s don’t interfere with their ability to work or live independently. Keep in mind that these symptoms might not be Alzheimer’s at all, but simply normal changes from aging.
Stage 3: Mild Decline
It’s at this point that you start to notice changes in your loved one’s thinking and reasoning, such as:
- Forgets something they just read
- Asks the same question over and over
- Has more and more trouble making plans or organizing
- Can’t remember names when meeting new people
Stage 4: Moderate Decline
During this period, the problems in thinking and reasoning that you noticed in stage 3 get more obvious, and new issues appear. Your friend or family member might:
- Forget details about themselves
- Have trouble putting the right date and amount on a check
- Forget what month or season it is
- Have trouble cooking meals or even ordering from a menu
- Struggle to use the telephone
- Not understand what is said to them
- Struggle to do tasks with multiple steps like cleaning the house.
Stage 5: Moderately Severe Decline
Your loved one might start to lose track of where they are and what time it is. They might have trouble remembering their address, phone number, or where they went to school. They could get confused about what kind of clothes to wear for the day or season.
You can help by laying out their clothing in the morning. It can help them dress by themselves and keep a sense of independence. If they repeat the same question, answer with an even, reassuring voice. They might be asking the question less to get an answer and more to just know you’re there. Even if your loved one can’t remember facts and details, they might still be able to tell a story. Invite them to use their imagination at those times.
Stage 6: Severe Decline
As Alzheimer’s progresses, your loved one might recognize faces but forget names. They might also mistake a person for someone else, for instance, think their wife is their mother. Delusions might set in, such as thinking they need to go to work even though they no longer have a job. You might need to help them go to the bathroom. It might be hard to talk, but you can still connect with them through the senses. Many people with Alzheimer’s love hearing music, being read to, or looking over old photos.
At this stage, your loved one might struggle to:
- Feed themselves
- Swallow
- Get dressed
They also might have:
- Weight loss
- Skin infections
- Pneumonia
- Trouble walking
- Changes in their sleeping patterns
Stage 7: Very Severe Decline
Many basic abilities in a person with Alzheimer’s, such as eating, walking, and sitting up, fade during this period. You can stay involved by feeding your loved one with soft, easy-to-swallow food, helping them use a spoon, and making sure they drink. This is important, as many people at this stage can no longer tell when they’re thirsty. In this stage, people with Alzheimer’s disease need a lot of help from caregivers. Many families find that, as much as they may want to, they can no longer take care of their loved one at home. If that’s you, look into facilities such as nursing homes that provide professional care day and night.
When someone nears the end of their life, hospice may be a good option. That doesn’t necessarily mean moving them to another location. Hospice care can happen anywhere. It’s a team approach that focuses on comfort, pain management and other medical needs, emotional concerns, and spiritual support (if desired) for the person and their family.
SYMPTOMS OF ALZHEIMER DISEASE
Early symptoms include:
- Memory loss
- Misplacing items
- Forgetting the names of places and objects
- Repeating themselves regularly, such as asking the same question several times
- Becoming less flexible and more hesitant to try new things
Middle-stage symptoms include:
- Increasing confusion and disorientation
- Obsessive, repetitive or impulsive behavior
- Delusions (believing things that are untrue)
- Problems with speech or language (aphasia)
- Disturbed sleep
- Changes in mood, such as frequent mood swings, depression and feeling increasingly anxious, frustrated or agitated
- Difficulty in performing spatial tasks, such as judging distances
- Agnosia
Later symptoms include:
- Difficulty in changing position or moving around without assistance
- Considerable weight loss – although some people eat too much and put on weight
- Gradual loss of speech
- Significant problems with short and long-term memory
COMMON TESTS & PROCEDURES
- Physical examination: Checking the patients for their reflexes, ability to get up from a chair and walk across the room as well as their muscle tone and strength.
- Neurological examination: Check for the sense of sight and hearing, coordination and balance.
- Complete blood count (CBC): To check Liver functions, Folate (folic acid) test, Vitamin B12 concentration, Electrolyte (sodium, potassium, creatinine, glucose, calcium) and blood glucose levels, Thyroid function tests, HIV test (ELISA).
- CT scan: CT scan of the head is performed to check the severity of brain degeneration.
- Magnetic resonance imaging (MRI): MRI scan of the brain provides more detailed aspects of brain, like the presence of a tumor or nerve damage etc.
- Electroencephalogram (EEG): To find abnormal brain wave activity.
- Positron emission tomography (PET): Identifies amyloid proteins which are associated with Alzheimer’s disease.
LIFESTYLE PRACTICES THAT HELPS
Research shows that practicing heart-healthy lifestyle choices, such as
- Exercising
- Eating plenty fruits and vegetables
- Avoiding stress,
- Not smoking
- Drinking alcohol in moderation, and
- Managing conditions like diabetes, hypertension, and atherosclerosis, can help with Alzheimer’s disease.
