What is Alzheimer's disease?
Alzheimer's disease is a progressive neurodegenerative condition which affects the brain cells, nerves and neurotransmitters. Alzheimer's is the most common type of dementia and is an umbrella term for conditions which cause the degeneration of brain function and subsequently affect behaviour and memory.
Alzheimer's disease is characterised by abnormal collections known as amyloid plaques and tangled webs of fibres known as neurofibrillary tangles, which are made up of misplaced strains of protein.
Causes and risk factors
The precise reason for the development of Alzheimer's disease is not fully understood. It results from a deterioration of the brain cells but it is not known what causes the cells to waste away. However, a number of risk factors have been identified; risk factors augment the threat of developing a condition but do not necessarily cause the condition. The most significant risk factor for Alzheimer's disease is age: the risk of Alzheimer's increases with age and doubles every five years once you reach the age of 65.
There are three genes that have been identified with reference to early-onset Alzheimer's disease, which affects people before the time they reach the age of 30. Other genetic mutations that result in an abnormal collection of amyloid proteins, which are associated with sporadic Alzheimer's disease (age-related), have also been identified. Alzheimer's disease can run in families, but the risk is only slightly higher for a person who has a family history of the condition.
Alzheimer's disease affects people in different ways and this means that individuals can display varied symptoms. The condition generally affects people in different stages and symptoms include:
- Speech problems
- Forgetting things and problems with memory
- Mood swings
- Changes in behaviour, including obsessive and repetitive behaviour
- Disturbed patterns of sleep
- Struggling to distinguish between what has really happened and what you have imagined
- Speech problems
- Appearing disorientated
- Difficulty swallowing
- Problems changing position
- Loss of appetite
- Increased susceptibility to infection
- Loss of memory (both short-term and long-term)
Diagnosing Alzheimer's disease
It can be difficult to make a diagnosis of Alzheimer's disease because many of the early symptoms, including forgetfulness, are confused with the natural signs of ageing. The symptoms are also similar to a range of other conditions, including vitamin deficiency, anxiety, problems with the thyroid gland and a brain tumour. Doctors recommend arranging an appointment if you experience any of the following symptoms:
- Forgetting things on a regular basis
- Speech problems
- Changes in your behaviour
- Experiencing difficulty with daily tasks
There is no single examination to diagnose or rule out Alzheimer's disease, but tests which may be used during the diagnostic process include:
- CT (computed tomography) scan
- MRI (magnetic resonance imaging) scan
- Blood test; used to rule out other conditions
- Physical examination
There is currently no known cure for Alzheimer's disease and the aim of treatment is to ease symptoms and promote independent living for as long as possible. However, a number of medications are used to ease symptoms, including:
The type of medication employed will depend on the severity of the disease. In a few cases a combination of medicines will be more effective than a single drug. Possible side-effects of medications prescribed for Alzheimer's disease include:
What is the prognosis for Alzheimer's disease?
There is no known cure for the condition and symptoms will gradually become worse over time. People with the condition often require round-the-clock care, especially in the advanced stages of the disease. The most common causes of death for Alzheimer's patients are other illnesses and infections, such as pneumonia.
The life expectancy for people with Alzheimer's disease varies: on average people die around 5 years after diagnosis but some people can live for much longer.