This is a disease characterized by irreversible, progressive and gradual loss of memory and thinking skills due to destruction of brain cells, eventually the victim can not perform the known daily activities and  depends on others. This mostly occurs after 60 years, though early onset Alzheimer can occur at 30, 40 or 50 years. Alzheimer’s disease is named after Dr. Alois Alzheimer, a German psychiatrist. In 1906, Dr. Alzheimer noticed changes in the brain tissue of a woman who had died of an unusual mental illness. Her symptoms included memory loss, language problems, and unpredictable behaviour. After she died, he examined her brain and found many abnormal clumps (now called amyloidal plaques) and tangled bundles of fibres (now called neurofibrillary tangles). Plaques and tangles in the brain are two of the main features of Alzheimer’s disease.  

Causes:

 It is not known exactly what causes this process to begin, but people with Alzheimer's disease have been found to have abnormal amounts of protein (amyloid plaques) and fibres (tau tangles) in the brain.

These reduce the effectiveness of healthy neurons (nerve cells that carry messages to and from the brain), gradually destroying them.

Over time, this damage spreads to other areas of the brain, such as the grey matter (responsible for processing thoughts) and the hippocampus (responsible for memory).

Risk factors:

Age

Age is the greatest factor in the development of Alzheimer's disease. The likelihood of developing the condition doubles every five years after you reach 65 years of age. However, it is not just older people who are at risk of developing Alzheimer's disease.

Family history

Genetic factors contribute to the risk of developing Alzheimer’s disease. Though in most cases, if you have a close family member with the condition, your risk of developing it is only slightly increased.

Down's syndrome

People with Down’s syndrome are at a higher risk of developing Alzheimer's disease. This is because people with Down's syndrome have an extra copy of chromosome 21, which codes for a protein involved in the cause of Alzheimer's disease. Therefore, people with Down's syndrome produce more abnormal protein, which could contribute to developing Alzheimer's disease.

Head injuries

People who have had a severe head injury have been found to be at a higher risk of developing Alzheimer's disease.

Heart diseases

There are some heart diseases where blood supply to the brain is impaired. Brain does not get oxygen and nutrient and become a risk factor for Alzheimer’s disease.

Other risk factors

High blood pressure, Diabetes, High/Abnormal cholesterol, smoking, alcoholism, drug addiction, depression etc.

Clinical features

The usual first symptom noticed is short term memory loss which progresses from seemingly simple and often fluctuating forgetfulness (with which the disease should not be confused) to a more pervasive loss of short-term memory, then of familiar and well-known skills or objects or persons. Since family members are often the first to notice changes that might indicate the onset of the disease they should learn the early warning signs. Aphasia, disorientation and disinhibition often accompany the loss of memory.

Alzheimer’s disease may also include behavioral changes, such as outbursts of violence or excessive passivity in people who have no previous history of such behavior. In the later stages, deterioration of musculature and mobility, leading to bedfastness, inability to feed oneself, and incontinence, will be seen if death from some external cause (e.g. heart attack or pneumonia) does not intervene. Average duration of the disease is approximately 7–10 years, although cases are known where reaching the final stage occurs within 4–5 years, or in some reported cases up to 21 years.

Stages and symptoms

Mild — At the early stage of the disease, patients have a tendency to become less energetic or spontaneous, though changes in their behavior often go unnoticed even by the patients’ immediate family. This stage of the disease has also been termed Mild Cognitive Impairment (MCI) although this term remains somewhat controversial.

Moderate — As the disease progresses to the middle stage, the patient might still be able to perform tasks independently, but may need assistance with more complicated activities.

Severe — As the disease progresses from the middle to late stage, the patient will undoubtedly not be able to perform even the simplest of tasks on their own and will need constant supervision. They become incontinent of bladder and then incontinent of bowel. They will eventually lose the ability to walk and eat without assistance.

Language becomes severely disorganized, and then is lost altogether. They may eventually lose the ability to swallow food and fluid and this can ultimately lead to death.

Diagnosis

There is no single test that can show whether a person has Alzheimer's. While physicians can almost always determine if a person has dementia, it may be difficult to determine the exact cause. Diagnosing Alzheimer's requires careful medical evaluation, including:

A thorough medical history, mental status testing, a physical and neurological exam

Tests (such as blood tests and brain imaging) to rule out other causes of dementia-like symptoms.    

Treatment

There is no cure for AD. The goals of treatment are:

Slow the progression of the disease (although this is difficult to do)

Manage symptoms, such as behaviour problems, confusion, and sleep problems

Change your home environment so you can better perform daily activities

Support family members and other caregivers

Drug treatment

Medicines are used to help slow down the rate at which symptoms become worse. The benefit from these drugs is usually small.

Medicines for AD include:

Donepezil (Aricept), rivastigmine (Exelon), and galantamine (Razadyne),  Memantine (Namenda). Side effects include stomach upset, diarrhea, vomiting, muscle cramps, and fatigue, agitation or anxiety.

Other medicines may be needed to control aggressive, agitated, or dangerous behaviors. Examples include haloperidol, risperidone, and quetiapine. These are usually given in very low doses due to the risk of side effects including an increased risk of death.

Prevention

Regular exercise

Participating in regular exercise has many benefits, and warding off dementia appears to be one of them.  Aerobic activity three times a week for 40 minutes is strongly supported by research. It's important to not only walk leisurely, but to try to break a sweat and get the heart rate up.

Control high blood pressure, diabetes, high cholesterol

Quit smoking, Quit drink alcohol  or drink in moderation

Keep stress to a minimum

Too much is not good for the brain. There is increasing evidence that activities like mindfulness meditation and yoga are good for the brain, Arnold noted.

Sleep

Adults should get anywhere between 7-9 hours of good quality sleep. Doctors recommend not watching T.V. or using the phone or tablet for at least 20 minutes before winding down to sleep as it keeps the brain active for longer.

Keep the mind active

Regular cognitive activities such as reading, writing, socializing, learning new skills or doing puzzles help keep the mind active.

Alzheimer’s Disease International (ADI) stated September 2013 is the second global World Alzheimer’s Month, an international campaign to raise awareness and challenge stigma. The theme for World Alzheimer's Month 2017 is  'Remember me'.

The month is being observed by Sir William Beveridge Foundation-Bangladesh by writing articles, talking on dementia in TV channels with a view to disseminating information on early symptoms, early diagnosis and care of the dementia sufferers.

Courtesy: Alzheimer’s Disease International(ADI)

LT COL (RETD) DR AN M SHAHIDUL ALAM

Medical Director

Sir William Beveridge Foundation-Bangladesh