How is dementia diagnosed?

Information on dementia diagnosis

Recognising the symptoms

Symptoms of dementia can be difficult to diagnose as they can vary from person to person and can depend on the level of progression and severity. Visit our Recognising the signs of dementia page for more information on symptoms.

Often it is a person's relative, carer or friend, rather than the person themselves, who notices changes in their behaviour or problems with their memory.

If you are concerned that you have dementia, it's important that you talk to your GP. If you have concerns about a friend or a relative, encourage them to speak to their own GP.


Visiting your GP

Visiting a GP is the first step in getting a diagnosis. When assessing dementia, patients will be asked about their symptoms, their physical and mental health and any medication they are taking.

The GP will look at the patient's medical history and carry out a physical examination to rule out other conditions which have similar symptoms to dementia. If a GP feels that dementia is a possibility, then they will refer the patient to see a specialist.


Referral to a dementia specialist

It's a good idea for the patient to write down any questions they may have before a visit, and they should make a note of any medical terms that are mentioned during the referral.

The specialist who carries out the examination may be an elderly-care physician or a psychiatrist. They may run some tests to help with the diagnosis.


Assessing mental abilities to diagnose dementia

The mini mental state examination (MMSE) is a commonly used test. It does not diagnose dementia; however, it is a useful tool in assessing mental abilities.

The MMSE comprises a series of short exercises. Examples include memorising a short list of objects and then repeating them, and writing a short, grammatically correct sentence.

The test allows a doctor to assess the person's short and long-term memory, as well as their attention span, language and communication skills. However, it's important to note that test scores may be influenced by a person's level of education and so cannot be relied upon alone.


Blood tests for dementia

A blood test to check overall health can rule out other conditions that may be responsible for symptoms.


Dementia brain scans

CT scans are needed to check for evidence of other possible problems that could explain a person's symptoms, such as a stroke or brain tumour.

MRI scans can provide detailed information about blood vessel damage that occurs in vascular dementia, plus any shrinking of the brain (atrophy). If the results of a patient's scan are uncertain then other scans and procedures may be recommended.


Receiving a formal diagnosis

If a patient receives a diagnosis for dementia, the type will determine the next steps.

Although it's never easy being diagnosed with dementia, it can help the patient and their family and friends to better understand the condition so they can manage their symptoms and maintain a good quality of life for as long as possible.

For links to useful information, advice and support, visit our Resources for dementia page.