Alzheimer's disease is most common in people over the age of 65, and affects slightly more women than men.
The risk of Alzheimer's disease and other types of dementia increases with age, affecting an estimated 1 in 14 people over the age of 65 and 1 in every 6 people over the age of 80.
However, around 1 in every 20 cases of Alzheimer's disease affects people aged 40 to 65.
Receiving a diagnosis
As the symptoms of Alzheimer's disease progress slowly, it can be difficult to recognise that there's a problem. Many people feel that memory problems are simply a part of getting older.
However, a timely diagnosis of Alzheimer's disease can give you the best chance to prepare and plan for the future, as well as receive any treatment or support that may help.
If you're worried about your memory or think you may have dementia, it's a good idea to see your GP. If you're worried about someone else, you should encourage them to make an appointment and perhaps suggest that you go along with them.
There's no single test that can be used to diagnose Alzheimer's disease. Your GP will ask questions about any problems you are experiencing and may do some tests to rule out other conditions.
If Alzheimer's disease is suspected, you may be referred to a specialist memory service to:
There's no cure for Alzheimer's disease, but medication is available that can help relieve some of the symptoms and slow down the progression of the condition in some people.
Various other types of support are also available to help people with Alzheimer's live as independently as possible, such as making changes to your home environment so it's easier to move around and remember daily tasks.
Psychological treatments such as cognitive stimulation therapy may also be offered to help support your memory, problem solving skills and language ability.
On average, people with Alzheimer's disease live for around 8 to 10 years after they start to develop symptoms. However, this can vary considerably from person to person. Some people with the condition will live longer than this, but others will not.
Alzheimer's disease is a life-limiting illness, although many people diagnosed with the condition will die from another cause.
As Alzheimer’s disease is a progressive neurological condition, it can cause problems with swallowing. This can lead to aspiration (food being inhaled into the lungs) which can cause frequent chest infections. It's also common for people with Alzheimer’s disease to eventually have difficulty eating and to have a reduced appetite.
There's increasing awareness that people with Alzheimer’s disease need palliative care. This includes support for families, as well as the person with Alzheimer's.
Can Alzheimer's disease be prevented?
As the exact cause of Alzheimer's disease isn't clear, there's no known way to prevent the condition. However, there are things you can do that may reduce your risk or delay the onset of dementia, such as:
The symptoms of Alzheimer's disease progress slowly over several years. Sometimes these symptoms are confused with other conditions and may initially be put down to old age.
The rate at which the symptoms progress is different for each individual and it's not possible to predict exactly how quickly it will get worse.
In some cases, infections, medications, strokes or delirium can be responsible for symptoms getting worse. Anyone with Alzheimer's disease whose symptoms are rapidly getting worse should be seen by a doctor, so these can be managed.
Stages of Alzheimer's disease
Generally, the symptoms of Alzheimer's disease are divided into three main stages.
In the early stages, the main symptom of Alzheimer's disease is memory lapses. For example, someone with early Alzheimer's disease may:
forget about recent conversations or events, or misplace items
forget the names of places and objects, or have trouble thinking of the right word
repeat themselves regularly, such as asking the same question several times
show poor judgement or find it harder to make decisions
become less flexible and more hesitant to try new things
There are often signs of mood changes, such as increasing anxiety or agitation, or periods of confusion.
As Alzheimer's disease develops, memory problems will get worse. Someone with the condition may find it increasingly difficult to remember the names of people they know and may struggle to recognise their family and friends.
Other symptoms may also develop, such as:
increasing confusion and disorientation – for example, getting lost, or wandering and not knowing what time of day it is
obsessive, repetitive or impulsive behaviour
delusions (believing things that are untrue) or feeling paranoid and suspicious about carers or family members
Alzheimer's disease is caused by parts of the brain shrinking (atrophy), which affects the structure and function of particular brain areas.
It's not known exactly what causes this process to begin. However, in the brains of people with Alzheimer's disease, scientists have found amyloid plaques (abnormal deposits of protein), neurofibrillary tangles (containing tau) and imbalances in a chemical called acetylcholine.
It's also common to have a degree of vascular damage 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 several areas of the brain. The first areas affected are responsible for memories.
Although it's still unknown what triggers Alzheimer's disease, several factors are known to increase your risk of developing the condition.
Age is the single most significant 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's not just older people who are at risk of developing Alzheimer's disease. Around 1 in 20 people with the condition are under 65. This is called early onset Alzheimer's disease and it can affect people from around the age of 40.
The genes you inherit from your parents can contribute to your risk of developing Alzheimer's disease, although the actual increase in risk is small if you have a close family member with the condition.
However, in a few families, Alzheimer's disease is caused by the inheritance of a single gene, and the risks of the condition being passed on are much higher.
There's currently no cure for Alzheimer's disease, although medication is available that can temporarily reduce some symptoms or slow down the progression of the condition in some people.
Support is also available to help someone with the condition cope with everyday life.
If you're diagnosed with Alzheimer's disease, it's helpful if your health and social care needs are assessed and plans made for the future.
A care plan is a way of ensuring you receive the right treatment for your needs. It involves identifying areas where you may need some assistance, such as:
what support you or your carer need for you to remain as independent as possible
whether there are any changes that need to be made to your home to make it easier to live in
whether you need any financial assistance
Healthcare professionals (such as your GP or psychiatrist) and social care services (which is normally your local council working with the NHS), will usually both be involved in helping draw up and carry out care plans.
A number of medications may be prescribed for Alzheimer's disease to help temporarily improve some symptoms and slow down the progression of the condition.
Donepezil, galantamine and rivastigmine (known as AChE inhibitors) can be prescribed for people with early to mid-stage Alzheimer's disease. Memantine may be prescribed for people with mid-stage disease who cannot take AChE inhibitors, or for those with late-stage disease.
There's no difference in how well each of the three different AChE inhibitors work, although some people respond better to certain types or have fewer side effects.
All of these medications can only be prescribed by specialists such as psychiatrists, neurologists and geriatricians. They may be prescribed by your GP on the advice of a specialist.
If you're caring for someone with Alzheimer's disease, your views should be taken into account when prescribing medication, as well as at regular assessments. These assessments take place to ensure the medication is having a worthwhile effect and to identify and monitor side effects.
more rarely, slowing of the heartbeat – which can cause issues if you already have problems with your heart rhythm.
These side effects are more likely to occur at the beginning of therapy or when the dose is increased. Your doctor should review your medical history and your other medications to check the suitability and risk of interactions.
If you have Alzheimer's disease, you may find it useful to:
keep a diary and write down things you want to remember
pin a weekly timetable to the wall
put your keys in an obvious place, such as in a large bowl in your living room
have a daily newspaper delivered to remind you of the day and date
put labels on cupboards and drawers
keep useful telephone numbers by the phone
write yourself reminders – for example, put a note on the front door to remind you to take your keys with you if you go out
programme people's names and numbers into your telephone
set the alarm on your watch to act as a reminder
install safety devices such as gas detectors and smoke alarms throughout your home
It may also be helpful to get in touch with a local or national Alzheimer's or dementia support group, such as the Alzheimer's Society, for more information and advice about living with Alzheimer's disease.
People with dementia often live for many years after their diagnosis. However, as it's a progressive condition, it can be helpful and reassuring for both you and your family if you make plans for the future.
Advance care planning means considering, discussing and possibly recording your wishes and decisions for future care. It's about planning for a time when you may not be able to make some decisions for yourself.
In the earlier stages of the disease, you should have the opportunity to discuss with health professionals and your family about the future. This may involve the use of:
Although the outlook is variable, dementia is a life-limiting illness and can begin to affect multiple body systems in the later stages.
End of life care, or palliative care, provides support for people with an incurable illness, so they're able to live as well and as comfortably as possible until their death. It also involves support for family members. Care may be provided at home, a hospice, a care home or hospital.
For people nearing the end of life, their care team should assess their needs, make them feel comfortable and allow them to die with dignity in a place of their choosing.
Stan Lintern has had Alzheimer's disease for 10 years. He is cared for by his wife Denise, who helped to set up the Maidstone branch of the Alzheimer's Society and runs the helpline. She has been awarded an MBE for services to her local community. They have three children.
"I was 49 when Stan was diagnosed. He'd been having problems with his memory for a bit and, after taking early retirement, he was lacking in motivation. We thought it was due to him missing his work. His behaviour began to be a bit odd at times, so when I was seeing our GP, I mentioned it. The GP suggested that Stan go for an appointment. After about six months of extensive tests, Stan was diagnosed with Alzheimer's.
"It was a devastating shock, but also good, because at least we knew what we were dealing with. It had been horrible not knowing what was causing his weird behaviour.
"For the first few years, we carried on with normal life. Stan was a Premier League table tennis player and he still enjoyed doing that. He continued to drive and we went on lots of holidays. He was a very meticulous man and liked everything to be 'just so'. But, as the Alzheimer's took over, he just decided he wasn't going to do things any more. I think he thought that if he couldn't do it the way he liked to do it, he wasn't going to bother anymore.
"Every time there has been a big change with Stan, I have to stop and take stock. Stan needs full-time care now. He's in a wheelchair and needs to be fed. He doesn't speak anymore and I'm not sure that he understands what I'm saying. I have some outside help during the week, but mostly it's down to me.
"We still go away. I have a hoist for getting him around indoors and a transporter 'truck' with a hydraulic tail lift to go out in. We still like going to Holland to see my cousins and their families, and visiting various places in the UK. The only thing we don't do is fly anywhere. I don't feel a prisoner because I've made sure that I can be independent and that we can get away. Stan is always more awake and aware when we're doing something different."