Getting a dementia diagnosis

It can be difficult to diagnose dementia, particularly in the early stages. A number of tests and assessments may be necessary to achieve a definitive diagnosis – and to eliminate other potential illnesses with dementia-like symptoms. Most people will initially see their GP to discuss concerns, perhaps over memory and communication problems or changes in behaviour.

A doctor may offer a preliminary diagnosis before referring the person to a memory clinic, neurologist or psychiatrist. Confirmation of a diagnosis is likely to be achieved through reviews of medical and personal histories, an assessment of the person’s mental abilities, a series of blood, glucose and urine tests and brain scans.

An early diagnosis of dementia is so, so important. Once diagnosed, I knew what I was up against.

Norman McNamara (known as Norrms) talking about his diagnosis in a YouTube video

You may also be interested to read the feature on ‘Supporting carers’ in the section on ‘Carers of people with dementia’.

Diagnosis – the facts

There has been an increase in the number of people diagnosed with dementia in England and Wales – but it is a sad fact that fewer than half the people living with dementia have a diagnosis. More than 400,000 people living with dementia are not receiving any of the benefits, support and drug treatments that can come from receiving a diagnosis, according to the Alzheimer’s Society. Figures published by the charity in February 2012 show that about 283,000 people in England and Wales have been diagnosed, a rise of about 18,000 in a year. Some areas of England and Wales have had a decrease in diagnosis rates (Alzheimer’s Society 2012).

Recent research from the University of Leicester demonstrates that many GPs are struggling to correctly identify people in the early stages of dementia (Mitchell et al 2011). GPs’ variable knowledge of – and attitude to – dementia play a key role in dementia recognition and ultimately in the number of people diagnosed. Dr Alex Mitchell, a consultant psychiatrist with the Leicestershire Partnership NHS Trust and a researcher at the University of Leicester, says:

GPs working in busy settings struggle to identify early dementia... based on their initial clinical judgment. This is particularly the case for patients living alone where no informant is available and when patients have relatively preserved daily function.

(University of Leicester press release, 2011)

The reality is that many people miss out on a diagnosis because their symptoms are mistaken by family and friends as signs of ageing. Elizabeth Ashton’s mother, Pamela, was diagnosed with vascular dementia in 2008 but had shown signs of the disease for at least 10 years before her death in 2011. Elizabeth told the Alzheimer’s Society:

I thought her forgetfulness was just a sign of ageing and pursuing a diagnosis at the time just didn’t occur to me or my GP. I can see now that we should have been more aware, and an early diagnosis would have been a great help. She might have responded to medication had she been diagnosed earlier, and we would have had a greater understanding of the difficulties she faced.

(Alzheimer’s Society press release, 22 February 2012)

The time it takes to a make a diagnosis can vary enormously. The Alzheimer’s Society says that, if scans and other investigations are required, it could take 4 to 12 weeks, depending on waiting lists (see Factsheet 426, Diagnosis and assessment). If the person is in the early stages of dementia, a 6- to 12-month period of monitoring may be needed before a diagnosis can be made. This, of course, can cause stress and uncertainty for all involved – particularly the person awaiting the diagnosis and close family and friends.

Seeing a GP

This is the usually the first – and frequently the hardest – step for people on the road to diagnosis. In having the opportunity to discuss concerns over their health and mental wellbeing, it is important that they are accompanied by a partner, close family member or friend to provide moral support and help them come to terms with a potential diagnosis of dementia.

Some people may choose not to see a doctor because they do not realise – or do not accept – there is anything wrong with them. Others may be afraid of having their suspicions confirmed. They may have to be encouraged to visit a GP for a physical reason (such as poor eyesight), for a blood pressure check or for a review of any medication they take.

A carer describes the difficulties of getting his wife’s dementia diagnosed in a healthtalk website video:

The GP suggested she almost certainly was starting to develop Alzheimer's disease which was a fear she’d had. The GP didn’t leave it at that fortunately but referred us to a local hospital. The doctor there, who took great interest in these kinds of situations, said something wasn’t quite right as far as the diagnosis...went. She (my wife) had scans... and they both showed no brain shrinkage, no problems, which puzzled him a bit.

So we were then referred to a consultant who went into more detail and admitted to being rather baffled and asked us if we were prepared to see a professor at the medical research council, which we duly did. We had a full day’s appointment. They wrote and asked if my wife would be prepared to go into hospital for a week for full tests to further try to establish exactly what was wrong. It eventually turned out to be Pick’s disease.

What a doctor may check and ask

Most people with suspected dementia will go to a doctors’ surgery to see their GP. Some doctors, however, will prefer to make a home visit to observe and assess someone’s behaviour in their own environment. A GP will check a person’s blood pressure, temperature and pulse, listen to their heart and lungs and collect blood and urine samples for further tests to be carried out. The doctor will ask what potential signs of dementia have been noticed and when they began, how often they occur and whether they are getting worse.

The GP may ask a series of questions designed to test the person’s memory and reasoning skills. The doctor is also likely to carry out a detailed review of any medication taken and ask about personal and family medical history, diet, smoking, intake of alcohol and exercise. The doctor will welcome notes – perhaps kept by the patient, a partner, close family member or a care worker – that outline when any symptoms or changes first happened. The GP may feel able to make a diagnosis at the conclusion of the assessment or may refer the person to a memory clinic or specialist.

Cultural diversity is an important consideration in the assessment process. Dementia assessments need to be culturally appropriate and recognise the impact of culture on individual behaviour. An interpreter may be vital for a proper assessment.

Referral to a specialist

A GP is the most likely person to arrange for someone with suspected dementia to see a specialist. The doctor may suggest that one or more of the following consultants be seen: a neurologist (who specialises in brain disorders and usually has experience in diagnosing dementia); a psychiatrist (who specialises in diagnosing and treating mental health problems, including dementia; a geriatrician (who specialises in physical illnesses and disabilities linked to old age).

Memory assessment tests

The most commonly used memory test for people with suspected dementia is the MMSE (Mini Mental State Examination). NICE (the National Institute for Health and Care Excellence) recommends the test when deciding whether drug treatment for Alzheimer’s disease should be prescribed and is used by many health professionals. The test – with questions testing memory, reasoning and verbal abilities – is helpful in establishing problems a person may be experiencing. But the MMSE is not a test for Alzheimer’s disease or any other form of dementia. It is considered to be just one part of the process of deciding whether someone has dementia and the severity of the condition.

Memory clinics

For people who are experiencing problems with their memory, a memory clinic can carry out baseline memory assessments as well as offering advice, information and support about managing memory problems. If medication is prescribed, the clinic can provide regular reviews and answer questions. A range of professionals may work together in a memory clinic, as part of a multidisciplinary team.

Brain scans

Doctors may suggest that a person with suspected dementia have a brain scan to help confirm a diagnosis. A scan can detect a number of conditions, including tumours and strokes, and may show brain shrinkage and indicate a loss of function in certain areas of the brain. One or more checks can be suggested through: CAT (computerised axial tomography) scans, which use X-rays to take pictures of the brain; MRI (magnetic resonance imaging) scans, which use radio signals to create an image of the brain; SPECT (single photon emission computerised tomography) scans, which look at how blood flows through the brain; and EEGs (electroencephalograms), which detect and record electrical activity patterns and check for abnormalities.

Who gives the diagnosis?

The GP will, in most cases, tell a patient about a diagnosis of dementia. If the person has been referred to a specialist for further tests or brain scans, reports of those will be sent to the GP. In some cases, a doctor may decide a diagnosis is too much for the person to cope with and may initially inform a partner or close relative.

Who else may a person with dementia see?

A person with suspected dementia may come into contact with a range of health and social care professionals. Consultants usually operate within specialist teams, including nurses, psychologists, occupational therapists and social workers. Nurses who work with people with dementia, and those caring for them, include: community mental health nurses (or community psychiatric nurses, known as CPNs), who work in the community, providing treatment, care and support for people with mental health problems and dementia; district or community nurses, who provide care and advice for people living at home; and practice nurses, who work with doctors in GP practices.

Clinical psychologists, who often work with consultants in memory clinics, assess memory and learning abilities. Occupational therapists can advise people on ways of maintaining their independence including carrying out adaptations and using special equipment. Social workers may be involved in assessing someone’s need for care services and home care workers may be brought in to help with personal and other care. Physiotherapists may be asked to advise on exercise for people, particularly in the early stages of dementia. Dieticians may be asked to provide guidance on nutrition, poor appetite, weight loss or weight gain.

Dementia advisers, available in many areas of the UK, fulfil the key role of supporting people with dementia, as well as their supporters and carers. They provide a quality information and signposting service tailored to meet individual needs, empower people to access information and to live well with dementia, and work closely with other health and care professionals to improve outcomes.


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  • What the research says: Early signs and diagnosis