Alzheimer’s disease is the most common form of dementia, a disorder that impairs mental functioning.Alzheimer's disease (AD) is a progressive neurological disorder in which the death of brain cells causes memory loss and cognitive decline. The disease starts mild and gets progressively worse over a period of few years.
Causes of Alzheimer's disease:
During the course of the disease, proteins build up in the brain to form structures called ‘plaques’ and ‘tangles’. This leads to the loss of connections between nerve cells, and eventually to the death
Of nerve cells and loss of brain tissue leading to brain shrinkage. People with Alzheimer’s also have a shortage of some important chemicals in their brain. These chemical messengers help to transmit signals around the brain. When there is a shortage of them, the signals are not transmitted as effectively and leading to improper functioning of nerves.
Alzheimer’s is a progressive disease. This means that gradually, over time, more parts of the brain are damaged. As this happens, more symptoms develop. They also become more severe.
Symptoms of Alzheimer's disease:
For most people with Alzheimer’s, the earliest symptoms are memory lapses. In particular, they may have difficulty recalling recent events and learning new information. These symptoms occur because the early damage in Alzheimer’s is usually to a part of the brain called the hippocampus, which has a central role in day-to-day memory function. Memory for life events that happened a long time ago is often unaffected in the early stages of the disease.
Memory loss due to Alzheimer’s disease increasingly interferes with daily life as the condition progresses. The person may experience-
- Lose items (like keys, glasses) around the house
- Struggle to find the right word in a conversation orforget someone’s name
- Forget about recent conversations or events
- Get lost in a familiar place or on a familiar journey
- Forget appointments or anniversaries.
They will also have, or go on to develop problems with other aspects of thinking, reasoning, perception or communication like.
- Language – struggling to follow a conversation or repeating themselves.
- Visuo-spatial skills – problems judging distance or seeing objects in three dimensions; navigating stairs or parking the car become much harder
- Concentrating, planning or organizing – difficulties making decisions, solving problems or carrying out a sequence of tasks (like cooking a meal repeatedly)
- Orientation – becoming confused or losing track of the day or date.
Later stages: As Alzheimer’s progresses, problems with memory loss, communication, reasoning and orientation become more severe. The person will need more day-to-day support from those who care for them.
Some people start to believe things that are untrue (delusions) or – less often – see or hear things which are not really there (hallucinations).
Many people with Alzheimer’s also develop behaviors that seem unusual or out of character. These include agitation (like restlessness or pacing), calling out, repeating the same question, disturbed sleep patterns or reacting aggressively.
In the later stages of Alzheimer’s disease someone may become much less aware of what is happening around them. They may have difficulties eating or walking without help, and become increasingly frail. Eventually, the person will need help with all their daily activities and become bed bound.
What can you expect from your doctor:
A detailed history regarding the symptoms will be obtained from main care giver. You can expect to get a detailed neurological examination and cognitive asessement.
We usually order blood test to look for any reversibel causes of Dementia. Brain imaging in the form of CT scan or MRI brain. EEG which is brain wave test in some cases. Very rarely Genetic test can be ordered.
It is quite important to remenber that none of the above test confirm Alzheimers Dementia but they are supportive and may confirm other reversibel causes. Some times it might require a re-assessment after a gap of few months to confirm the diagnosis of Alzheimers Dementia.
Treatment and prevention of Alzheimer's disease:
There is no known cure for Alzheimer's disease - the death of brain cells in the dementia cannot be halted or reversed.
The following are important elements of dementia care:
- Effective management of any conditions occurring alongside the Alzheimer's.
- Activities and/or programs of adult day care to keep them mentally active.
- Support groups and services both for patients and care givers.
There are two types of medication used to treat Alzheimer’s disease as discussed below. But on some occasions other drugs can be used to control behavior problems.
1.Cholinesterase inhibitors (donepezil, rivastigmine and galantamine):
They prevent an enzyme called acetylcholinesterase from breaking down acetylcholine in the brain. As a result, an increased concentration of acetylcholine leads to increased communication between nerve cells. This may temporarily alleviate or stabilise some symptoms of Alzheimer’s disease.
2.NMDA receptor antagonist (Memantine): used in moderate to severe cases.
The action of memantine is different from that of donepezil, rivastigmine and galantamine. Glutamate is another chemical that helps to send messages between nerve cells. Glutamate is released in excessive amounts when brain cells are damaged. This causes the brain cells to be damaged further. Memantine protects brain cells by blocking the effects of excess glutamate.
Medical conditions such as diabetes, stroke, heart problems, high blood pressure, high cholesterol and obesity in mid-life are all known to increase the risk of Alzheimer’s disease and vascular dementia. We can reduce their risk by keeping these under control.
Depression is a probable risk factor for dementia; getting it treated early is important.
People, who adopt a healthy lifestyle, especially from mid-life onwards, are less likely to develop Alzheimer’s disease. This means taking regular physical exercise and keeping to a healthy weight, not smoking, eating a healthy balanced diet and drinking only in moderation.
Leading an active lifestyle that combines regular physical, social and mental activity will help to lower risk.