The progression
and stages of
dementia
Factsheet 458LP
October 2020
Dementia affects everyone differently. This makes it hard to know exactly
how and when it will change over time. However, for some people with
dementia the symptoms will progress in a broadly similar way. It can be
helpful to think of this progression in three ‘stages’.
This factsheet is for anyone who is interested in the stages of dementia,
and how and why dementia progresses.
Dementia is a life-limiting condition and there is information about life
expectancy in this factsheet. Some people may nd this upsetting and
difcult to think about. For more general information about dementia see
factsheet 400, What is dementia?
The progression and stages of dementia2
Contents
n What does progression in ‘stages’ mean?
— How important are the stages?
n Why is dementia progressive?
n What affects the speed of progression?
— What if the person has a sudden change in symptoms?
n Early stage
— Symptoms of early-stage dementia
n Middle stage
— Symptoms of middle-stage dementia
n Later stage
— Symptoms of late-stage dementia
— How long will a person with dementia live for?
n Other useful organisations
The progression and stages of dementia3
The progression and stages
of dementia
What does progression in ‘stages’ mean?
There are many different types of dementia and all of them are
progressive. This means symptoms may be relatively mild at rst but they
get worse with time, usually over several years. These include problems
with memory, thinking, problem-solving or language, and often changes in
emotions, perception or behaviour.
As dementia progresses, a person will need more help and, at some point,
will need a lot of support with daily living. However, dementia is different
for everyone, so it will vary how soon this happens and the type of
support needed.
It can be helpful to think of dementia progressing in three stages – early,
middle and late. These are sometimes called mild, moderate and severe,
because this describes how much the symptoms affect a person.
These stages can be used to understand how dementia is likely to change
over time, and to help people prepare for the future. The stages also act
as a guide to when certain treatments, such as medicines for Alzheimer’s
disease, are likely to work best.
The progression and stages of dementia4
How important are the stages?
The stages of dementia are just a guide and there is nothing signicant
about the number three. Equally, dementia doesn’t follow an exact or
certain set of steps that happen in the same way for every person with
dementia.
It can be difcult to tell when a person’s dementia has progressed from
one stage to another because:
n some symptoms may appear in a different order to the stages described
in this factsheet, or not at all
n the stages may overlap – the person may need help with some aspects
of everyday life but manage other tasks and activities on their own
n some symptoms, particularly those linked to behaviours, may develop at
one stage and then reduce or even disappear later on. Other symptoms,
such as memory loss and problems with language and thinking, tend to
stay and get worse with time.
It is natural to ask which stage a person is at or what might happen
next. But it is more important to focus on the person in the present
moment. This includes their needs and how they can live well, and how
to help them with this.
For more support on living well with dementia see booklet 872, The
dementia guide (for people living with dementia) or booklet 600, Caring for
a person with dementia: a practical guide (for carers).
And for more information about treatment and support for the different
types of dementia see factsheets 401, What is Alzheimer’s disease?, 402,
What is vascular dementia?, 403, What is dementia with Lewy bodies
(DLB)? and 404, What is frontotemporal dementia (FTD)?
The progression and stages of dementia5
Why is dementia progressive?
Dementia is not a single condition. It is caused by different physical
diseases of the brain, for example Alzheimer’s disease, vascular dementia,
DLB and FTD.
In the early stage of all types of dementia only a small part of the brain is
damaged. In this stage, a person has fewer symptoms as only the abilities
that depend on the damaged part of the brain are affected. These early
symptoms are usually relatively minor. This is why ‘mild’ dementia is used
as an alternative term for the early stage.
Each type of dementia affects a different area of the brain in the early
stages. This is why symptoms vary between the different types. For
example, memory loss is common in early-stage Alzheimer’s but is very
uncommon in early-stage FTD. As dementia progresses into the middle
and later stages, the symptoms of the different dementia types tend to
become more similar. This is because more of the brain is affected as
dementia progresses.
Over time, the disease causing the dementia spreads to other parts of the
brain. This leads to more symptoms because more of the brain is unable
to work properly. At the same time, already-damaged areas of the brain
become even more affected, causing symptoms the person already has
to get worse. Eventually most parts of the brain are badly damaged by the
disease. This causes major changes in all aspects of memory, thinking,
language, emotions and behaviour, as well as physical problems.
For more information about how damage to the brain affects certain skills
and abilities, see factsheet 456, Dementia and the brain.
The progression and stages of dementia6
What affects the speed of progression?
The speed at which dementia progresses varies a lot from person to
person because of factors such as:
n the type of dementia – for example, Alzheimer’s disease tends to
progress more slowly than the other types
n a person’s age – for example, Alzheimer’s disease generally progresses
more slowly in older people (over 65) than in younger people (under 65)
n other long-term health problems – dementia tends to progress more
quickly if the person is living with other conditions, such as heart
disease, diabetes or high blood pressure, particularly if these are not
well managed
n delirium – a medical condition that starts suddenly (see ‘What if the
person has a sudden change in symptoms?’ on page 7).
There is no way to be sure how quickly a person’s dementia will progress.
Some people with dementia will need support very soon after their
diagnosis. In contrast, others will stay independent for several years.
Evidence shows that there are things a person with dementia can do to
keep their abilities for longer. For example, it can be helpful to:
n maintain a positive outlook
n accept support from other people – including friends, family and
professionals
n eat and sleep well
n not smoke or drink too much alcohol
n take part in physical, mental and social activity (see factsheet 529,
Physical activity and exercise for more information).
The progression and stages of dementia7
It is also important for a person with dementia to try to keep healthy by:
n managing any existing health conditions as well as possible
n having regular health check-ups, particularly for their eyes and ears
n asking their GP about jabs – for seasonal u and pneumococcal
infection (that can lead to bronchitis or pneumonia).
This is to prevent new or existing health problems developing or getting
worse. This can make a person’s dementia progress more quickly.
For information see factsheet 425, How the GP can support a person
with dementia.
What if the person has a sudden change in symptoms?
Not every change in a person’s condition is a symptom of dementia. If the
person’s mental abilities or behaviour changes suddenly over a day or two,
they may have developed a separate health problem.
For example, a sudden deterioration or change may be a sign that an
infection has led to delirium. Or it may suggest that someone has had a
stroke. A stroke is particularly common in some kinds of vascular dementia
and may cause the condition to get worse in a series of ‘steps’. When a
stroke happens, it causes more damage to the brain which can result in a
noticeable decline in the person’s abilities.
In any situation where a person with dementia changes suddenly, or just
does not seem themselves, speak to a doctor or nurse as soon as you can.
The progression and stages of dementia8
Early stage
Dementia affects everyone differently and early symptoms are often
relatively mild and not always easy to notice. Many people at this stage
stay largely independent and only need a bit of assistance with daily living.
It is important to focus on what the person can do and not to take over
and do things for them. Instead, try doing things with them, for example
helping the person develop a routine, reminder lists and prompts, and
use technology.
For more information see factsheet 526, Supporting a person with
memory loss and booklet 1506, Keeping active and involved (for people
living with dementia).
The early stage of dementia is when many people choose to make plans
for the future, while they still have the ability (‘mental capacity’) to do so.
For more information see factsheets 472, Lasting power of attorney and
463, Advance decisions and advance statements.
Symptoms of early-stage dementia
As a very rough guide, the early stage of dementia lasts on average about
two years. This stage is when the following common symptoms start to
affect the person’s daily life:
n The most well-known early symptoms are memory problems. For
example, a person may not recall recent events or may keep losing
items (such as keys and glasses) around the house. Memory loss is often
the rst and main symptom in early Alzheimer’s disease. It is also seen,
although less often, in early vascular dementia and DLB. Memory loss is
not common in early FTD.
n Difculties in thinking things through and planning are also common at
this stage. A person may get confused more easily and nd it harder to
plan, make complex decisions (for example, about nances) or solve
problems.
The progression and stages of dementia9
n Language and communication are often affected early on. A person
may struggle to nd the right word in a conversation, or they might not
follow what is being said. Speech can also be affected when someone
with vascular dementia has had a stroke. Specic types of FTD
cause particular early problems with language – see factsheets 500,
Communicating and 404, What is frontotemporal dementia (FTD)? for
more information.
n Poor orientation is another feature of early stage dementia. A person
may no longer recognise where they are and so get lost, even in a place
that is familiar to them.
n People may also struggle with visual-perceptual difculties. This can
cause problems judging distances, for example when using stairs. They
are more common in early-stage Alzheimer’s disease and DLB than in
vascular dementia or FTD. Visual-perceptual difculties are different
from the visual hallucinations (often of animals or people) that are a
feature of early-stage DLB.
n Changes in mood or emotion are common at this stage. The person
may be more anxious, frightened or sad, and so at risk of depression.
It is also common to become more irritable – perhaps in frustration at
lost abilities – or easily upset. A person can often be more withdrawn,
lack self-condence and lose interest in hobbies or people. For more
information see factsheet 444, Supporting a person with dementia who
has depression, anxiety or apathy.
Changes in behaviour are not common in early-stage dementia, other than
in FTD. A person with behavioural variant FTD may lose their inhibitions and
behave in socially inappropriate ways. They may also act impulsively and
lose empathy for others.
Signicant physical changes at this stage tend to be limited to DLB, where
problems with movement are similar to Parkinson’s disease. If someone
with vascular or mixed dementia has a stroke, this can lead to weak limbs
on one side.
The progression and stages of dementia10
Middle stage
In the middle stage of dementia, symptoms become more noticeable
and the person will need more support in managing daily life. The person
may now need frequent reminders and some help to wash and dress (for
example, having their clothes laid out for them).
Some people with dementia will benet from a paid carer coming into their
home. Or some may move into housing with dementia support on site
(known as extra-care housing or assisted living).
Symptoms of middle-stage dementia
For many people with dementia, the middle stage is when symptoms will
get worse. This is also when changes in behaviour generally start. This
stage of dementia is often the longest. On average it lasts about two
to four years, during which time symptoms are likely to develop in the
following ways:
n Existing problems with memory and thinking will worsen in the middle
stage. Many people nd it harder to recognise family or close friends.
They may confuse them with strangers. Remembering new information
will also get harder. This may cause the person to repeat the same
question over and over.
n The way a person speaks or uses language is likely to get worse at this
stage too. They may have problems nding the right word and they may
forget what they are saying mid-sentence. It may get harder for them to
follow what someone else is saying.
n Problems with orientation also become more severe. Someone may
get confused about the time of day – for example, they may get up and
dressed in the middle of the night. Or they might get confused about
where they are, even at home.
n Symptoms of apathy, depression and anxiety tend to continue into the
middle stage of dementia.
n In this stage many people start to strongly believe things that aren’t true
(delusions). They often feel that other people are going to harm them or
cannot be trusted (paranoia). It is very common for a person to believe
that someone is stealing from them or that a partner is being unfaithful.
The progression and stages of dementia11
n A person at this stage may also start to see and hear things that aren’t
there (hallucinations). This is more common in the middle stage of
Alzheimer’s disease than in vascular dementia. (Visual hallucinations in
DLB are a symptom in the early stage.)
Changes like these partly explain why the person can struggle to control
their emotions. Someone may get very easily upset, fearful, or angry – and
switch between these quite quickly. They might be reacting to a loss of
independence, misinterpreting things around them or frustrated that they
can’t communicate their needs.
For more information see factsheet 524, Understanding and supporting a
person with dementia.
Physical and behavioural changes in middle stage dementia
Changes in behaviour tend to start from the middle stage of dementia.
These changes are common and individual symptoms may come and go.
Changes in behaviour are some of the most challenging symptoms for
people with dementia and for those who support them.
Common changes that are seen in all types of dementia at this stage
can include:
n agitation and restlessness – for example, dgeting or walking up
and down
n screaming or shouting
n repetitive behaviour – for example, repeatedly pulling at clothes or
asking the same question over and over
n following a carer around (trailing) or constantly checking that they
are near
n disturbed sleep patterns – sleep is particularly disrupted, and in a
different way, in a person with DLB
n losing inhibitions – for example, saying things that aren’t appropriate or
undressing in public (not just in FTD).
The progression and stages of dementia12
People may become more agitated, aggressive or confused in the late
afternoon or early evening, a pattern known as ‘sundowning’.
These behaviours are often because the person has a specic physical or
emotional need (for example, hunger or boredom) that is not being met.
For more information about these changes and how to deal with them, see
factsheets 525, Changes in behaviour, 509, Aggressive behaviour and 501,
Walking about.
In all types of dementia, difculties with using the toilet can start at this
stage. In DLB, problems with movement are likely to get worse. A person’s
walking gets slower and less steady, leading to a higher risk of falls.
Later stage
By this stage dementia will have a severe impact on most aspects of a
person’s life. The person will eventually need full-time care and support
with daily living and personal care, such as eating, washing and dressing.
This support can be provided by care at home but is more often given in a
care home setting.
Symptoms of late-stage dementia
Symptoms of all kinds are likely to cause the person considerable
difculties by this stage, but altered perception and physical problems are
often the most noticeable. By the late stage of dementia, the symptoms
of all types of dementia become very similar. This stage tends to be the
shortest. On average it lasts about one to two years.
For more information see factsheet 417, The later stages of dementia.
The progression and stages of dementia13
Memory and language difculties in the later stages of dementia
Many people will struggle with memory of recent events and they may
often think they are at an earlier period of their life (‘time shifting’). This can
cause challenging situations, for example if they ask to see someone who
is no longer alive.
People in the later stages may also stop recognising familiar places,
objects and people. A person may not recognise themselves in a mirror, nor
a close friend or family member. This is because they only remember how
the person looked when they were much younger.
If a person speaks more than one language, they may lose the one they
learned later in life. Eventually, they may only understand the language of
their childhood.
A person’s spoken language in late-stage dementia may eventually be
reduced to a few words or lost altogether. They may also understand
fewer words. But a person may still be able to understand gestures,
facial expressions and body language. They may also use non-verbal
communication to express their feelings or needs.
Mood, emotions and perceptions in the later stages of dementia
Changes in mood remain in the later stages of dementia. Depression and
apathy are particularly common.
Delusions and hallucinations (especially of sight and hearing) are most
common in the late stage of dementia. They are not always distressing
but they can explain some changes in behaviour, because the person’s
perception of reality is altered.
People with late-stage dementia often respond more to senses than to
words. For example, they may like listening to songs or enjoy textures (for
example, the feel of different types of material).
The progression and stages of dementia14
Changes in behaviour in the later stages of dementia
The changes in behaviour that can happen in the middle stage of dementia
can also all happen in the late stage.
Aggression at this stage is often a reaction to personal care. Someone may
hit or push away those trying to help them, or shout out to be left alone.
The person with dementia may have felt scared, threatened or confused.
Restlessness is also very common. Sometimes the person may seem to
be searching for someone or something.
As in other stages, it is also important to consider whether the person has
other needs that aren’t being met. Someone with late-stage dementia
will often be unable to tell others how they are feeling. A sudden change in
behaviour can point to a medical problem (for example, pain, infection or
delirium).
Physical difculties in the later stages of dementia
The physical changes of late-stage dementia are partly why the person is
likely to need much more support with daily living. At this stage they may:
n walk more slowly, with a shufe and less steadily – eventually they may
spend more time in a chair or in bed
n be at increased risk of falls
n need a lot of help with eating – and so lose weight
n have difculty swallowing
n be incontinent – losing control of their bladder and bowels.
The person’s reduced mobility in particular raises their chances of blood
clots and infections. These can be very serious or even fatal so it is vital
that the person is supported to be as mobile as they can.
The progression and stages of dementia15
How long will a person with dementia live for?
Whatever kind of dementia a person has, their life expectancy is on
average lower. This is why dementia is called a life-limiting condition.
This can be very upsetting to think about. However, it’s important to
remember that, no matter how a person’s dementia changes over time,
there are ways to live well with the condition. Good support can make a
huge difference to the person’s quality of life at all stages.
Dementia reduces life expectancy in two ways. First, some of the diseases
that are closely linked to Alzheimer’s disease and vascular dementia,
such as diabetes and cardiovascular disease, lower life expectancy. For
example, vascular dementia is closely linked to heart disease and stroke. A
person with vascular dementia is at risk of dying, at any stage of dementia,
from one of these.
The other way that dementia reduces life expectancy is through the
effects of severe disease. By the late stage a person is often very frail with
a weakened immune response, likely to be spending a lot of time in bed
and possibly having problems swallowing. These all make them much more
likely to develop other medical problems that can lead to death, such as
infections (like pneumonia) or cardiovascular problems (like a blood clot
in the brain or lungs). This is why the late stage of dementia is often the
shortest.
A person with dementia can also die at any stage from another condition
not closely related to their dementia. Cancer and lung disease are
common examples.
How long a person lives with dementia varies greatly from person to
person. It depends on many factors, such as the ones listed on page 6.
Other factors include:
n how far the dementia had progressed when the person was diagnosed
n what other serious health conditions the person has – such as diabetes,
cancer or heart problems (and how long they have had these)
The progression and stages of dementia16
n how old the person was when their symptoms started – older people
(over 65) are more likely than younger people (under 65) to have other
health conditions that may lower their life expectancy. A person in their
90s who is diagnosed with dementia is more likely to die from other
health problems before they reach the later stages than is a person
diagnosed in their 70s.
Does the type of dementia affect life expectancy?
The type of dementia a person has can also affect how long they live
with dementia. These gures for the number of years a person may live
after a diagnosis are just averages and some people live longer than this.
This information may be upsetting to read and think about but it is very
important to remember that, with the right support, people with dementia
can live well at all stages.
The average life expectancy gures for the most common types of
dementia are as follows:
n Alzheimer’s disease – around eight to 10 years. This is less if the person
is diagnosed in their 80s or 90s. A few people with Alzheimer’s live for
longer, sometimes for 15 or even 20 years.
n Vascular dementia – around ve years. This is lower than the average for
Alzheimer’s mostly because someone with vascular dementia is more
likely to die from a stroke or heart attack than from the dementia itself.
n DLB – about six years. This is slightly less than the average for
Alzheimer’s disease. The physical symptoms of DLB increase a person’s
risk of falls and infections.
n FTD – about six to eight years. If a person has FTD mixed with motor
neurone disease – a movement disorder, their dementia tends to
progress much quicker. Life expectancy for people who have both
conditions is on average about two to three years after diagnosis.
To nd out about the support available to someone at the end of their life,
and to their carers, family and friends, see factsheet 531, End of life care.
You can also call Alzheimer’s Society on 0333 150 3456 for personalised
advice and support on living well with dementia, at any stage.
The progression and stages of dementia17
Other useful organisations
Carers UK
0808 808 7777 (9am–6pm Monday–Friday)
advice@carersuk.org
www.carersuk.org
www.carersuk.org/forum (online discussion forum)
Carers UK gives carers advice, information and support.
The Lewy Body Society
01942 914000
info@lewybody.org
www.lewybody.org
The Lewy Body Society raises awareness of DLB among the general public,
medical professionals and decision maker. It also provides information
resources for people with DLB and carers.
Rare Dementia Support
020 3325 0828
contact@raredementiasupport.org
www.raredementiasupport.org
Rare Dementia Support works to support people affected by ve rare
dementia conditions: familial alzheimer’s disease (FAD), frontotemporal
dementia (FTD), familial frontotemporal dementia (fFTD), posterior cortical
atrophy (PCA) and primary progressive aphasia (PPA).
Stroke Association
0303 3033 100 (Stroke Helpline, 9am–5pm Monday, Thursday and Friday,
8am–6pm Tuesday and Wednesday, 10am–1pm Saturday)
helpline@stroke.org.uk
www.stroke.org.uk
Stroke Association is the UK’s leading stroke charity. They provide
information and practical support to people concerned about or affected
by stroke.
This publication contains information and general advice. It should not be
used as a substitute for personalised advice from a qualied professional.
Alzheimer’s Society does not accept any liability arising from its use. We
strive to ensure that the content is accurate and up to date, but information
can change over time. Please refer to our website for the latest version and
for full terms and conditions.
© Alzheimer’s Society, 2021. All rights reserved. Except for personal use, no
part of this work may be distributed, reproduced, downloaded, transmitted
or stored in any form without the written permission of Alzheimer’s Society.
Alzheimer’s Society
is the UK’s leading
dementia charity. We
provide information and
support, improve care,
fund research, and create
lasting change for people
affected by dementia.
For support and advice,
call us on 0333 150 3456
or visit alzheimers.org.uk
Alzheimer’s Society operates in England, Wales and Northern Ireland.
Registered charity number 296645.
People affected by dementia need our
support more than ever. With your help we
can continue to provide the vital services,
information and advice they need.
To make a single or monthly donation,
please call us on 0330 333 0804 or go to
alzheimers.org.uk/donate
Factsheet 458LP
Last reviewed: October 2020
Next review due: October 2023
Our information is based on evidence and need, and is regularly updated
using quality-controlled processes. It is reviewed by experts in health and
social care and people affected by dementia.
Reviewed by: Prof Rob Howard, Professor of Old Age Psychiatry, Faculty of
Brain Sciences, University College London
This factsheet has also been reviewed by people affected by dementia.
To give feedback on this factsheet, or for a list of sources, please email
publications@alzheimers.org.uk
