The three stages of Alzheimer's disease

The symptoms of Alzheimer's disease progress gradually over several years. Symptoms can vary for each individual, and the rate at which they progress is also different, making it difficult to predict how long each stage will last. Knowing what to expect can help you plan ahead and get the support you need.

See also: Eight hidden signs of dementia

See also: People 'frequently misdiagnosed with common types of dementia'

The symptoms of Alzheimer's disease are divided into three main stages: early, middle, and late stage.

Early-stage symptoms
Early stage symptoms are characterised by memory problems. Someone with early Alzheimer's disease may:

In the early stages, these memory lapses are unlikely to interfere with a person's ability to work or do things independently. Because symptoms are mild, they can sometimes be confused with other conditions, or simply put down to old age.

As the conditions progresses, a person with Alzheimer's disease may:• show poor judgement, or find it harder to make decisions• withdraw from social situations and be less willing to go to new places or try new things• display changes in personality and mood, increasing anxiety or agitation, or inappropriate
Middle-stage symptoms
As the disease progresses further, memory problems become more pronounced. Someone with Alzheimer's disease in the middle stages may forget the names of people they know well and no longer recognise family and friends.

You may notice other symptoms develop, such as:

• confusion and disorientation – for example, getting lost in a familiar place
• not knowing what month, season, or time of day it is
• obsessive, repetitive or impulsive behaviour
• delusions – eg, think they need to go to work though they no longer have a job
• feeling paranoid and suspicious about carers or family
• increased problems with speech or language
• difficulty sleeping
• frequent mood swings, depression and anxiety
• problems performing spatial tasks, such as judging distances
• hallucinations

By the middle stages of the condition, they will need support to help them with everyday living. For example, they may need help with cooking, eating, washing, getting dressed and using the toilet.

Later-stage symptoms
In the later stages of the disease, symptoms become increasingly severe. This can be distressing both for the person with Alzheimer's and for their carers, friends and family.

Hallucinations and delusions are more likely and the person may be become increasingly agitated, violent, and suspicious of those around them.

A number of other symptoms may also develop as Alzheimer's disease progresses, such as:

• problems eating and swallowing
• difficulty changing position or moving around without assistance
• weight loss – though some people over eat and put on weight
• incontinence (bladder and bowel)
• gradual loss of speech
• short- and long-term memory loss

In the final stages of Alzheimer's disease, the person will need full-time care and assistance with things like eating and drinking, sitting up and using the toilet.

Other things that can affect symptoms
It's worth keeping in mind that certain things - such as an infection, medication, delirium, or a stroke – can affect symptoms. If a friend or relative with Alzheimer's disease seems to get worse suddenly, it's important to see your GP.

Help and support
Alzheimer's Society encourages anyone who is worried about their memory or health to seek the support of their GP. Alzheimer's Society National Dementia Helpline provides a range of advice and support for people who are concerned, whether about themselves or someone else. To speak to an advisor call 0300 222 11 22 or visit alzheimers.org.uk. You can also download a Worried About Your Memory Booklet.