What is the difference between dementia and Alzheimer’s disease?

Dementia is a condition where problems with memory or other types of thinking make it hard for a person to do everyday activities by themselves. It can be caused by several different diseases that affect the brain. Alzheimer’s disease is the most common cause of dementia.

Alzheimer’s disease starts in the brain many years before symptoms start to show. Early symptoms are mild and so don’t stop someone doing their normal everyday activities. It’s only later that symptoms become severe enough to be called ‘dementia’. 

Other common causes of dementia include vascular disease, which prevents blood from getting to the brain properly, and Lewy body disease.

Just as with Alzheimer’s, these diseases develop in the brain over many years. Eventually they lead to vascular dementia and Lewy body dementia.

What is dementia?

Dementia is a group of symptoms. It’s caused by different diseases that damage the brain. The symptoms get worse over time and include: 

  • memory loss 
  • confusion and needing help with daily tasks 
  • problems with language and understanding  
  • changes in behaviour. 

Dementia is progressive, which means symptoms may be relatively mild at first, but they get worse over time.  

What is Alzheimer’s disease?

Alzheimer’s disease is the most common cause of dementia. About two out of three people living with dementia in the UK have Alzheimer’s disease, which is sometimes called “Alzheimer’s”.
 
Alzheimer’s disease is a physical illness which damages a person’s brain. It starts many years before symptoms start to show.
 
Early symptoms of Alzheimer’s are mild and don’t prevent someone from doing everyday activities by themselves. This is called mild cognitive impairment (MCI).

It’s often not possible at this stage to say for sure that the person’s symptoms are being caused by Alzheimer’s disease, as there could be many other causes.
 
Eventually Alzheimer’s disease causes so much damage to the brain that the person develops dementia. Technically this type of dementia is called ‘Alzheimer’s disease dementia’. However, most people – including healthcare professionals – just call it ‘Alzheimer’s disease’.
 
For most people, Alzheimer’s disease starts in and around the part of the brain involved in memory. However, in some rarer types of dementia the disease starts in a different part of the brain and so causes a different set of symptoms. This is called ‘atypical Alzheimer’s’. For example, posterior cortical atrophy is caused by Alzheimer’s in the back of the brain and mostly causes problems with vision.  

What causes Alzheimer's disease

The causes of Alzheimer’s disease are very complex, but one key part is the build-up of two substances inside the brain called amyloid and tau. When conditions in the brain aren’t right, these clump up and form tiny structures called plaques and tangles. These make it harder for the brain to work properly. 

Over time the disease causes certain parts to become smaller. It also reduces the amount of important chemicals needed to send messages around the brain. 

There is currently no cure for Alzheimer’s disease. However, treatments may temporarily ease some symptoms or slow down their progression in some people. 

What are the main other types of dementia – and what causes them? 

Vascular dementia: this the second most common type of dementia. It is caused by problems with the blood supply to parts of the brain.

Lewy body dementia: Lewy bodies are tiny clumps of protein that build up in the brain. When this happens, it leads to Lewy body disease. There are two main types: 

  • Dementia with Lewy bodies:  When the first signs of Lewy body disease are symptoms of dementia, this is known as ‘dementia with Lewy bodies (DLB)’. 
  • Parkinson’s disease dementia: Lewy body disease can also cause Parkinson’s disease, which mostly involves problems with movement but can also lead to dementia several years later. If it does, this is known as Parkinson’s disease dementia. 

Frontotemporal dementia: this is a less common type of dementia. It can be caused by several different types of disease but they all mostly affect the front or the sides of the brain, known as the frontal and temporal lobes.
 
Mixed dementia: A diagnosis of mixed dementia is generally used when someone has a mixture of clinical symptoms from two or more different types of dementia – for example, if they have symptoms of both Alzheimer’s disease and dementia with Lewy bodies.  

How do I know what type of dementia I have? 

A diagnosis of dementia needs to be made by a healthcare professional who specialises in dementia, usually following a detailed assessment at a local memory service.  

When someone gets a diagnosis of dementia they should ideally be told by the doctor what type they have. This doesn’t always happen though. Sometimes it’s hard to tell what the cause of a person’s dementia is – particularly during the earlier stages.

It’s not always essential to know straight away what the cause of dementia is, but it can help to make better sense of the person’s symptoms and to get the right treatment.  

Does Alzheimer’s Society support people with dementia, as well as Alzheimer’s disease? 

We support anyone who has dementia. We can help guide people with mild cognitive impairment or who are worried about their memory. Find out how Alzheimer's Society can support you. 

We’re a vital source of support, giving help to everyone who needs it today, and hope for everyone in the future. 

This post was first published in July 2018 and most recently updated in February 2023.

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141 comments

My mother is nearly 90 and has vascular dementia and alzeimers. Her condition has deteriorated rapidly over the last 12 months. As a family we do as much for her as possible. I have a care agency looking after her twice a day. We take her out often trying to stimulate her mind and keep her as active as possible. However I'm starting to wonder if my mum would get more stimulation in a care home. I very much want to keep her at home but I am concerned in doing what is best for her.

So, still don't really know the difference??

Thank you, My. dear husband passed away March 2018,he was in a hospice for the second time when his distressing symtons came to light in nov 18, he had pulmonary fibrosis of the lungs for a long time and broncyectisis. The change in the brain was drastic he had a brain scan done at hospital.. The consultant phyciatrist, came and told me his brain for his age of 63 was not what he expected and said there had been some damage to FT. After the long long time he had suffered with add ons Type I I diab, He said there was nothing could be done, and he wasn’t able to stay and I brought him home rather than be sent to another place to die.i have only just discovered from this site what this FTD is , no one explained it to me at the time . Now my self and family have our 90 yr old father , memory failing and been wandering, he is waiting for an appointment for a confirmed diagnosis, I find it all very worrying, I am 66. If you can advise. Please do. Dad has been allocated a social worker.

Hi,
My dad has got mixed dementia.
He becomes very aggressive. The most worrying for me is that his sleeping hours are getting shorter and shorter. Is there any medication for dementia that can ease him to sleep.

Last year my husband was diagnosed with mixed etiology dementia ... I cant find much info on it and he doesnt like it when I question our doctor ? Can you help me understand what this means. The doctor who diagnosed him told us about the three stages and that there would be 2 years to each stage and on the 3rd stage his body would start shutting down . He has started galantamine

Thank you for this informative article. My mum has been diagnosed with vesicular dementia and Alzheimer’s at a reasonably young age, only 65yo! It’s devastating and although not as bad as it could be right now she’s deteriorating quickly! I live abroad and am visiting right now but I know I need to come home, and I’m considering caring for my and dad who is also very poorly and cant cope with my
Mum. my question is, has anyone got any advise on how I can make that a full/part time job for me???

Hi Emily.

I am sorry to read of your mum’s diagnoses and I do recognise how devastated you must be feeling, 65 is a very young age.

I can understand your moving back home as it sounds as if you are also worried about your dad as he is poorly and hasn’t got the resources to cope with your mum’s vascular dementia.

I can also understand your question regarding how to make your caring role a full time job.

I’m afraid to say that it is not easy to be paid as a carer when you are a relative of the person you are caring for. Citizen Advice have some information on direct payments, which allow the person with dementia to receive cash payments from their local authority to buy in their own care services. I’m supplying you with the link to this information from their website for you.

https://www.citizensadvice.org.uk/wales/family/looking-after-people/dir…

However you will see from reading this information that the local authority has guidelines when it comes to paying relatives who live with the relative they are caring for.

You would be entitled to certain benefits however and I am supplying you with the link to the money advice services as they have quite a comprehensive guide to the benefit entitlements for carers.

https://www.moneyadviceservice.org.uk/en/articles/benefits-and-tax-cred…

We also have a great deal of information on our website that I think will be helpful.

I’m supplying you with the link to our information on benefits. Also the local authority has a duty of care towards your mum and they will need to allocate a social worker to carry out a needs assessment. They must also include a needs assessment for the carer too and I have supplied our information on this for you as well.

https://www.alzheimers.org.uk/get-support/legal-financial/benefits-deme…

https://www.alzheimers.org.uk/get-support/legal-financial/personal-budg…

https://www.alzheimers.org.uk/get-support/legal-financial/needs-assessm…

I do hope this is helpful, please feel free to contact us again or call our Helpline if you need any further information or support.

Our Helpline is open Monday to Wednesday (9am-8pm), Thursday to Friday (9am–5pm) and Saturday to Sunday (10am-4pm), and can be reached on 0300 222 11 22.

Live Online Advice
Monday to Friday (9am–12pm)
Monday evening (6pm-8pm)
https://www.alzheimers.org.uk/get-support/national-dementia-helpline/li…

Best regards, and please do get in touch again anytime you need to.

Elaine
Helpline Adviser

My mum was diagnosed with vascular dementia about 5 years ago.My brother has always lived with her and they were really close. Sadly he died 25th September this year. I have been with her since until I will be taking her back home with me.I was advised not to tell her of his death just to keep saying he is out.When it starts to get dark she is constantly asks to go home to see him (even though she is at her home)and also asking where is he until she goes to bed.She gets very anxious Will this ease as time goes by and will things be worse for her
when I take her to my home?

My mum has been diagnosed with Alzheimer's very recently. She has short term memory loss and repeats herself over and over again but otherwise seems in good health. She's 82 and does not want to accept the diagnosis. She does daily crossword puzzles and says that shes's not 'stupid'.
We have explained that it doesn't mean she's stupid but she won't listen. She sits with the family and sometimes looks a bit left out because she can't always follow the conversation.
However despite all of this she still loves to play cards and is the life and soul of the game, laughing, teasing others etc. She also plays games with the youngest family members such as cowboys and other gun firing games (not always what we would want but she comes alive).
Do you think it best to continue doing these activities and not worry too much about the diagnosis until more symptoms develop?

Dear Clare,

Thank you for contacting the Alzheimers Society.

It sounds as if your mum is still enjoying her life and continues to do all the things which she enjoys, which is great.

Maybe when you are having family gatherings, perhaps try to focus on your mum and maybe talk about things which she can remember.

Other ways of supporting your mum would be to encourage her to take part in activities she enjoys or find useful. Spending time with her– having a cup of tea and a chat with her, or doing something together helping her to have a daily routine, reminiscence therapy, adapting the environment if this is affecting the person (for example if it’s too hot, cold, loud or bright).
I am enclosing some links to information which you might find helpful, and remember, we are here if you feel it would help to talk to one of our advisers. We may have a local office in your area and here is the link with information on how to search for the nearest Dementia support worker. If you prefer you could contact us and we could search for you:

https://www.alzheimers.org.uk/find-support-near-you

https://bit.ly/2vv7wK0 (What is Alzheimers disease?)
https://bit.ly/2RTrxm3 (Staying healthy)
https://bit.ly/2Tc6AEB (Exercise and physical activity)
https://bit.ly/2CNT6K1 ( Understanding and supporting a person with dementia)
https://bit.ly/2OXGExZ (Council tax)
https://bit.ly/2RuiIzg (Carers looking after yourself)
https://bit.ly/2C5BckH (the dementia guide)
https://bit.ly/2QwnvQ1 (Publications the full list)

You might also want to register on our forum, where there is a section for carers where you can find information and support, and here is the link.
https://www.alzheimers.org.uk/get-support/talking-point-our-online-comm…

In answer to your question regarding your mums refusal to accept her diagnosis, it is very common for people with dementia to have limited or no awareness of their cognitive problems. In some cases this might be because they are in denial, but in most cases it is caused by a lack of insight – the person cannot understand that they have dementia. It is often difficult to know whether a lack of awareness is caused by denial or loss of insight. Problems can also be worsened by loss of short-term memory, where the person is unable to recall the problems they've had or misjudge the frequency of these problems.

Loss of insight is viewed as a physical process that is a part of the disease itself. It is related to loss of activity in specific areas of the frontal cortex.

Denial is a psychological reaction. It is thought of as a ‘defence mechanism’ that helps a person to cope with the situation. Denial is not the person's 'fault' – it operates at an unconscious level.

Denial may resolve over time as the person is gradually able to accept what is happening to them, whereas lack of insight may worsen as dementia progresses.

• Approach the person in a supportive way and be kind, gentle and calm – anger may well make the problem worse. Remember, the person's lack of acceptance is most likely not deliberate.
• Don’t argue with the person, or try force them to face reality – if they lack insight, then getting them to admit they are unwell will be unhelpful because they are not capable of really understanding what this means.
• It may help carers to know that a lack of awareness can be selective – a person may be aware of some symptoms yet completely oblivious to others. This can make it seem like the person is doing it on purpose, but this is not the case.

I hope you find this information helpful, but do come back to us if we can help in any way.

Kind Regards,

Mary

Helpline Adviser (Alzheimer's Society)

My mom is 76 yrs old & has dementia. We have never been told what kind. I started seeing signs a year or so ago and it progressed rapidly. She was living in a very bad situation without proper food, her meds & dr care. She was literally cut off from any of her family & friends being able to visit or have any say in her care. Five weeks ago I finally got control of her and after 2 weeks in the hospital with extremely high blood pressure & a brain bleed I had to put her in a nursing home. She talks to pictures, thinks people that have been dead many years comes to see her. She can’t remember anything you tell her for more than a minute. She has to wear diapers which she takes off constantly. She can’t dress herself properly nor has any idea of personal hygiene. She cries to go home daily and when I visit which I do every other day she begs the whole time for me to take her home. It is heartbreaking and I leave in tears. The anxiety raises her blood pressure, gives her very bad headaches & causes her to hardly be able to get her breath. She is on Paxil plus gets Ativan 3 times a day. Is it normal that she deteriorated so rapidly and is she likely to remain begging to go home and crying so much? Should she be adjusting to the nursing home by now if she’s ever going to? She’s been there a month. Could she need to be on different meds since these aren’t helping? My heart is broken for her & I feel so helpless.

Hi Paula

I am so sorry to hear about your mom and the sad results of her dementia. The behaviour you describe is unfortunately a common consequence of changes in her brain, but hard for the family to bear Many people with dementia ask to go home, but it is often an indefinable place that they remember from a long time ago when they felt happy and safe, and some people no longer even recognise their home if they do visit. She hasn’t been in the nursing home long, so it all must feel confusing and strange, but hopefully she will eventually get into a routine and make some connection with others there and feel less anxious. As you see her often, it may be less stressful for her if you wait until she is occupied and slip away rather than any parting that may remind her of home? And some drugs take a while before they are effective.

Admiral Nurses can advise on medication: 0800 888 6678.

Do call our helpline if you would like to talk things through: 0300 222 1122.

My Mum suffered Meningococcal meningitus.
This left her brain damaged.
We were told she would have early onset Dementia.
It's 12years on now and she is deteriorating rapidly.
Her stubborn proud husband won't discuss her future and won't relinquish power of attorney. He's in his 80s and in poor health.
I hover around just waiting for something awful to happen.
I have managed to implement day care for 2 days and carers going in just recently.
He tries to keep her in bed on the days she isn't going to day care or when my sister or myself are not able to take her for the day.
We both work and have families.
So difficult as her husband isn't my father.

My father is being diagnosed with vascular dementia I am so so sad about it this 3 years ago just when he was 68 I am just worried that it could be genetic and I could have it one day I can see you s an horrible disease... is that the case? His mum ( my grandma) had in the eighties arteriosclerosis which she died at the age of 84 .. is that connected to him etc .. many thanks in advance.! Kind regards

Hi Lorella, I’m so sorry to hear about your father’s diagnosis. I hope he is doing well.

When a close relative develops dementia many people worry that their condition may be heritable – that is, passed down from parent to child in the form of a ‘disease’ gene. Most forms of dementia do not work like this. Only a very small proportion of people with vascular dementia will have inherited such a gene from their parents. In most cases, vascular dementia is caused by the same kinds of factors that cause heart disease and strokes, such as smoking and high blood pressure. You can read more about the condition in our factsheet, 'What is vascular dementia?';

https://www.alzheimers.org.uk/about-dementia/types-dementia/vascular-de…

Or you can call the National Dementia Helpline on 0300 222 11 22 if you would like to talk about your father’s condition and how best to support him.

Hi. Having read all the various comments which I have found most helpful. Where do I go to express my concerns regarding myself in the first instance to even find out if this is affecting me? I am 70 active healthy and full of the desire for life. Thank you hopefully for your comments/advice. Don

Hi Don, thanks for your comment.

This page on our website is good starting place for anyone who is worried about their memory: https://www.alzheimers.org.uk/about-dementia/symptoms-and-diagnosis/wor…

If you are worried about your memory or experiencing other dementia symptoms, we always recommend speaking to your GP straight away. You can also call our helpline for more advice or with any questions you might have. Details of the helpline can be found at this link: https://www.alzheimers.org.uk/get-support/national-dementia-helpline

If you're just interested in learning more about things that can increase/reduce a person's risk of getting dementia, this is a good page to explore: https://www.alzheimers.org.uk/about-dementia/risk-factors-and-prevention

Hope this helps for now. If you have any other questions please don't hesitate to get in touch.

Kind regards,

Kyle (Alzheimer's Society)

Hi my 82 ye old mum has just been diagnosed with Alzheimer's and she is totally unaware that anything is wrong. She also blames things in being tired. What's your view on whether I try to tell her that she has now been officially diagnosed? I've had a discussion with her doctor and he says he's not a fan of telling people, he thinks it's better than she continues to be happy ' in her own little world'
I don't know if she's aware that she is forgetting things, she doesn't appear to, but surely it's better that she knows why she's having medication?

Hi Tracie, thanks for your comment. I am so sorry to learn that your mum is living with dementia, hopefully I’ll be able to give you some information to help with your query.

Lack of insight and awareness is a common symptom of dementia, therefore it may be possible that your mum is not aware of what is going on for her. Everyone will experience dementia differently, so what works for your mum may not work for others.

My advice therefore is to take your lead from your mum. If she is expressing confusion around taking medication or asking questions, and you feel that she will be able to understand and tolerate the answer, then it may be advisable to answer her questions.
Please be aware, however, that your mum’s cognitions and understanding will have been affected by dementia so her ability to reason and rationalise may be different from you or I. Her memory may also be affected, therefore she may not remember your explanations and it can be unhelpful to constantly remind someone of what they have forgotten.

Any stress or anxiety can negatively affect the symptoms of dementia, so this may have been what the GP was referring to when advising to keep her happy in her own little world.
Pointing out a person’s failures, such as memory loss or reinforcing negatives, such as a dementia diagnosis, can affect a person’s self-esteem, which again will be unhelpful.

If your mum is understanding that her symptoms are due to tiredness then this is her absolute reality of the situation, some family members and carers find it helpful to respect their loved one’s reality rather than dispute it.

I do hope that this has been helpful. Here are some factsheets you might find useful also:

Communicating: http://bit.ly/2oTxBR0
Understanding and supporting a person with dementia: http://bit.ly/2rwdOY0

Please don’t hesitate to contact our Helpline on 0300 222 1122 if you require any further information, advice or support.

You may also find it helpful to visit our online forum 'Talking Point', as other people may have discussed similar issues. You don't have to sign up to search through the forum, so you could just read other peoples' posts and find out about their experiences. The forum can be found at: http://forum.alzheimers.org.uk/forum.php

We also have a Live Online Advice service which is available Monday to Wednesday (9am–12pm, and 6pm-8pm) and Thursday to Friday (9am-12pm), which can be found at http://www.alzheimers.org.uk/site/scripts/home_info.php?homepageID=428

Kind regards,

Helpline advisor

My 85 year old father in law has been diagnosed with Alzheimer's and dementia plus vascular dementia. Mother in law is the same age but seems in denial and keeps saying he can dress and shower himself plus eats what I give him. Father in law struggles with conversation and explaining what he wants. Would not go to any club or support group. How can the family help?

Hi Jan, I’m so sorry to hear about your father in law.

It’s quite common for older couples to stick together and refuse to accept that things have changed. And it can be difficult for people with dementia to understand that they might enjoy the stimulation of meeting new people and getting involved in activities. It often feels safer to keep to a familiar routine. In the same way, your mother-in-law may not appreciate that she may need support to understand dementia better and benefit from help and support to care for her husband as the disease progresses.

In these circumstances, other family members can act in their best interests by helping to get the support that they may need, rather that hoping that they will make these contacts themselves:

Assessment for care and support in England
http://bit.ly/2nqhDKE

There may be local Alzheimer’s Society services nearby that can offer face-to-face help, advice and support to both of them. Details can be found at:
https://www.alzheimers.org.uk/about-us/contact-us/alzheimers-society-regional-offices

And for details of other dementia support and activities in the area you can follow this link:
https://www.alzheimers.org.uk/find-support-near-you

You may also find it helpful to visit our online forum 'Talking Point', as other people may have discussed similar issues. You don't have to sign up to search through the forum, so you could just read other peoples' posts and find out about their experiences. The forum can be found at:
http://forum.alzheimers.org.uk

Anyone from the family can call our Helpline too: 0300 222 1122.

Thank you and i have done lists on Spotify and also have our own Karaoke system in our house and often have a sing song. Hes only early stages so far and im taking so many photos as he has no short term memory and forgets nights out and what happened. So far hes still working even though 80 but i have semi retired 60 to help him work as long as he can because apart from this you would not know hes 80. He is a piano tuner..music again haha.

Hello again Ann,

It sounds like you have a lovely musical home with the Karaoke system, and also the Spotify playlists.

With those - and your husband’s piano playing - it sounds very positive and stimulating. Even better to hear that he is still working. I wish you both well and I hope your days continue to be filled with music, singing and laughter. Do come back to us should you need to.

-
Helpline Advisor

my name is cam my mother was diagnose with dementia at88 l think shehad high blood pressure I failed to watch it more closer and I blame myself she got worse and she went to a home she passed away in 2014 at 92 I feel if I acted faster with her blood pressure she would not got dementia.