Basics of Alzheimer’s Disease

Alzheimer’s disease is the most common form of dementia, and it accounts for over 50-70% of all cases of dementia.  It is also progressive, which means that even when the early symptoms are subtle and easy to miss, it gets worse over time, eventually leading to death.

What characterizes Alzheimer’s is the appearance of amyloid plaques and tangles (neurofibrillary tangles) in the brain caused by abnormal protein deposits.

Amyloid plaques are clumps of toxic protein peptides or fragments, also called beta-amyloid.  Beta-amyloids start out as Amyloid Precursor Protein (APP), which are produced by cells for the cellular membrane.  When the APP becomes embedded or stuck in the membrane, certain enzymes snip or cleave the APP into fragments.  APP fragments generally release beneficial elements for the growth of neurons while interacting beneficially with the nucleus of the cell.  However, in some instances some APP fragments are snipped or cleaved at both ends, releasing the beta-amyloid peptide into space, which begins to stick to other beta-amyloid peptides.

These clumps or aggregates of beta-amyloid peptides may react with other cells and synapses, compromising their ability to function.  In time, these clumps of beta-amyloid peptides grow larger.  Other proteins and material become added, and they grow to become insoluble entites that are what are now known as amyloid plaques.

On the other hand, Neurofibrillary Tangles, also called tau, or simply tangles, are strands of twisted protein threads inside nerve cells.  While tau threads usually work by binding to microtubules to stabilize them, should they have an abnormal number of phosphate molecules attached to them, tau threads begin to come together, creating tangles within the cell.  As a result, the microtubules they are supposed to support disintegrate, and the internal transport network of neurons is damaged.

With the build up of both plaques and tangles inside the brain, neural connections are destroyed, also causing damage to the neurons until they eventually die.  When neurons die, the brain begins to shrink in what is known as brain atrophy.  In the final stages of Alzheimer’s, the brain tissue has shrunk significantly, and the damage has become widespread.

It is interesting to note that in general, damage seems to begin quite often in the hippocampus, which is essential for memories.  This is probably why memory loss is often one of the most noticeable and earliest symptoms of Alzheimer’s disease.

 

Signs and symptoms:

Alzheimer’s is a progressive disease, which means that it will only get increasingly worse with time.  Medical experts distinguish different stages of Alzheimer’s, and each stage is recognized by certain identified symptoms.  For early onset Alzheimer’s however, there are a few warning signs or early signs and symptoms to watch out for.  The difficulty is that they may sometimes be confused with normal aging difficulties.  The key here is to remember that dementia is not a normal part of aging.  While many people do suffer from the following symptoms now and then during the course of their life, if it happens repeatedly so that it begins to disrupt one’s ability to live a normal life, the best thing to do is to go to a doctor to get a proper diagnosis.  It is even possible that the cause of memory loss, for instance, is not dementia, but something treatable such as medication, alcohol, depression, or simple stress.

Some of the early warning signs and symptoms of Alzheimer’s Disease include:

  • short-term memory loss that is disruptive to one’s daily life
  • displays of apathy, depression, and irritability
  • a repeated inability to remember the same information, or asking the same question repeatedly
  • trouble with daily tasks, problem solving, organization and planning, and other complex tasks, even though these are things you normally do
  • confusion as to time and place, disorientation
  • difficulties with vocabulary both in speaking and writing: exchanging names of things, inability to find the right words
  • changes in vision
  • losing or misplacing things
  • social withdrawal, less interest in work; more time spent sitting, sleeping, or watching TV
  • lapses in judgment or decision-making, such as in handling money or in maintaining personal hygiene and grooming
  • sudden mood changes, and experiencing emotions such as fear, anxiety, or suspicion
  • difficulty with coordination and motor functions, such as in handling familiar objects
  • having less energy and drive in doing things

Mild Alzheimer’s can last anywhere from 2 -4 years.  Experts distinguish between three stages of this disease, and as this disease progresses, so do the symptoms.  Some of the symptoms that can manifest in moderate or middle stage Alzheimer’s, which can last from 2-10 years, can include the following:

  • persistent memory loss, including details about his life and identity of family and friends
  • rambling speech
  • unusual reasoning
  • confusion about current events, time and place
  • may wander and become lost even in familiar surroundings
  • sleep disturbances
  • behavioral and mood changes
  • delusions, aggression and uninhibited behavior
  • physical mobility and coordination is affected, experiencing slowness, tremors and rigidity
  • not dressing appropriately for the weather

Alzheimer’s culminates in the late or severe stage, lasting from 1-3 or more years.  The following symptoms become manifest, and round the clock support and care are needed because the person has become unable completely to care for himself.

  • loss of ability to remember
  • inability to communicate or process information
  • confusion about past and present
  • possible immobility
  • problems with swallowing and incontinence
  • extreme behavior and mood changes
  • hallucinations and delirium
  • weight loss, seizures, skin infections and other illnesses

Causes

The precise cause or causes of Alzheimer’s are not yet fully understood, though it is believed that Alzheimer’s may be caused by a combination of genetic, environmental and lifestyle factors.  There does seem to be some genetic component to Alzheimer’s, though some cases of Alzheimer’s do seem to occur without any family history of this condition.  Some external factors have been identified as increasing the risk for getting Alzheimer’s, and these include:

  • Down’s Syndrome
  • severe head trauma
  • high blood cholesterol
  • diabetes
  • smoking
  • obesity
  • heart disease
  • poor diet
  • stroke

The risk of getting Alzheimer’s does increase with age.  The initial symptoms usually appear at the age of 60, though younger individuals as young as 30 may also get Alzheimer’s, though this is usually rare.

Diagnosis

Early diagnosis is always best, but in cases of Alzheimer’s, this may not always be possible.  The difficulty is that it seems likely that internal damage to the brain may have already begun for about 10 years or more before the symptoms begin to manifest themselves.  The earlier the diagnosis can be made, however, will at least allow the patient to gain an understanding of his condition, to gain support and understanding from the people around him, and to make preparations.  The patient might also be able to modify personal behavior of lifestyle choices that contribute to the onset of Alzheimer’s, such as alcohol or smoking, high cholesterol levels and high blood pressure.  Any previous head injury or trauma might also be addressed and, where feasible, might be given appropriate treatment.

In any case, at present, there is no definitive test to diagnose for Alzheimer’s.  Many doctors will need to consult their patient’s medical history, ask questions, assess the symptoms, administer tests such as the Mini Mental State Examination (MMSE), and if possible, rule out other causes of the symptoms being experienced.  A CT scan and MRI may be given that would also rule out other possible causes such as tumors or fluid buildup inside the brain.  In early cases of Alzheimer’s, a brain scan may show a slight shrinking of the hippocampus and the surrounding brain tissues.

Treatment Options

There is, as yet, no cure for Alzheimer’s, and no proven method for prevention, although certain methods for prevention are currently being looked into.  Most of it involves reducing or modifying some of the external factors that have been shown to contribute to the onset of Alzheimer’s, such as medication and diet and lifestyle changes.  While it may seem clear that identified external factors do increase the risk for a person getting Alzheimer’s, eliminating or modifying these factors after the onset of Alzheimer’s has yet to be proven to slow the progress of this disease.

The current state of treatment options for Alzheimer’s fall mostly under the category of symptom management.  Medication offered for Alzheimer’s patients usually fall into two categories or types: Cholinesterase inhibitors that help with feelings of agitation and depression, and also support cell to cell communication inside the brain.  These drugs may also help with memory problems, concentration, and the ability to cope with some aspects of daily living such as shopping or cooking.

Cholinesterase inhibitors may sometimes be used together wtih Memantine (Namenda), for moderate to severe cases of of Alzheimer’s.  Memantine also helps in cell to cell communication in the brain, and it also helps to slow the progress of some of the symptoms of Alzheimer’s such as agitation, mental abilities and delusions.  It is to be noted that the relief that these drugs offer are only temporary, and while they may help in managing some of the symptoms, even delaying the progress of the disease for a short while, sometimes they may not have useful effect on the symptoms at all.

These prescribed drugs will not have the same effect on everyone, whether in its effectivity or in the resulting side effects.  Though for some, common side effects include nausea, vomiting, and diarrhea.  In some instances, there might also be insomnia, dizziness, muscle cramps, and fatigue.

The use of drugs or medication are sometimes supported by psychosocial intervention such as different types of therapy.  Such therapies might include having the person do activities that they enjoy, mentally stimulating activities, or supportive therapies to help the patient accept and adjust to their illness.  Other possible therapeutic treatments include reality orientation, or grounding the patient in time and place information to help them adjust to their surroundings.  Emotional support may also be given with discussions of past experiences and tangible exposure to familiar items from the past.  The effectivity of these varied forms of available therapy do vary from individual to individual, though there does seem to be some evidence that such therapies help in reducing some of the more challenging behaviors of patients with Alzheimer’s.

Finally, caregiving services must be looked into early on for people diagnosed with Alzheimer’s.  Gradually, a person becomes almost completely incapable of living independently, and caregiving becomes essential.  If someone in your family is diagnosed with Alzheimer’s, you should be able to look into the aspect of caregiving early on.  Will you be hiring a professional caregiver, or will you be tending to your loved one’s needs yourself?  Caregiving is challenging, frustrating, and many caregivers often do suffer from physical and emotion burnout.   If you do decide to take on the caregiving role yourself, prepare yourself by reading up on news and possible treatments for Alzheimer’s, take care of yourself physically and emotionally to help you cope with the caregiving responsibilities, and most of all – don’t hesitate to ask for help whenever you need it.

Prognosis

The outlook for those diagnosed with Alzheimer’s is, unfortunately, quite poor.  There is no cure for Alzheimer’s disease, and one can only expect the symptoms and the brain condition to get worse with time. Treatments such as drugs and therapies cannot halt the progression of the disease, and it is yet unclear whether or not they can add more time to a person’s life.  Treatment, on the whole, is directed more to helping a person cope with and manage the symptoms they are experiencing.

The length of time that they have depends largely on different variables such as the age at which the symptoms started and their severity.  If the symptoms began when a person is around 60-70, they can expect to live for an average of about 7-10 years, while those whose symptoms began in their 90s can usually expect to live for another about three years.  But these numbers are highly variable and depend on each individual case, and some can still expect to live a long time, ranging from an average of around 3-20 years.