Dr Lucio D’Anna is a Consultant Neurologist at the Department of Stroke & Neurosciences at Imperial College London NHS Trust. He is also Honorary Senior Lecturer at the Division of Brain Sciences, Imperial College London.
There are many reasons why people experience memory problems. Commonly it is simply due to age but sometimes it can be caused by other conditions. These can include stress or the early stages of a dementia, such as Alzheimer’s disease.
The aim of our Memory Clinic is to discover the cause of your memory problem and to provide you with the appropriate information, support and treatment that you need to help you to live well and independently.
What is ‘normal’?
It is perfectly normal to have occasional memory lapses and to lose things. It is normal to forget why we have gone upstairs, or to come back from a shopping trip without the very thing we went for. It is normal to have to search our brain for a name, sometimes. Our normal memory may suffer from impaired function through inattention, information overload or mild depression from time to time. Unless there is something wrong, we retain a huge store of general (semantic) knowledge, an ability to plan and manage our affairs and, under normal circumstances anyway, we retain our orientation in time and place.
What is dementia?
Dementia is a syndrome affecting higher functions of the brain. There are a number of different causes. Cognitive decline, specifically memory loss alone, is not sufficient to diagnose dementia. There needs to be an impact on daily functioning.
The specialist (ICD-10) classification of dementia is as follows:
- Memory decline. This is most evident in learning new information
- Decline in at least one other domain of cognition such as judging and thinking, planning and organising etc., to a degree that interferes with daily functioning
- Some change in one or more aspects of social behaviour e.g. emotional lability, irritability, apathy or coarsening of social behaviour
- There should be corroborative evidence that the decline has been present for at least 6 months
How to prevent dementia?
There is some emerging evidence to suggest that a proportion of new cases of dementia could be prevented by paying attention to vascular risk factors, this is summed up in the saying, ‘What is good for your heart is good for your head’. Keeping vascular risk factors under control is always going to be worthwhile, as is keeping weight down and exercising. Keeping mentally active and retaining social networks is also good.
How to diagnose dementia?
There’s no single test for dementia. A diagnosis is based on a combination of assessments and tests. These can be done in our Memory Clinic in a single day.
Taking a history
The specialist will
- ask how and when symptoms started and whether they’re affecting daily life
- check whether any existing conditions, such as heart disease, diabetes, depression or stroke, are being properly managed
- review any medication you’re taking, including prescribed medicines, those bought over the counter from pharmacies, and any alternative products, such as vitamin supplements
Mental ability tests to diagnose dementia
People with symptoms of dementia are given several different tests to check their mental abilities, such as memory or thinking. Most tests involve a series of pen-and-paper tests and questions, each of which carries a score.
These tests assess a number of mental abilities, including:
- short- and long-term memory
- concentration and attention span
- language and communication skills
- awareness of time and place (orientation)
It’s important to remember that test scores may be influenced by a person’s level of education.
For example, someone who can’t read or write very well may have a lower score, but they may not have dementia. Similarly, someone with a higher level of education may achieve a higher score, but still have dementia.
Blood tests to check for other conditions
In our Memory Clinic we will arrange for blood tests to help exclude other causes of symptoms that can be confused with dementia.
In most cases, these blood tests will check:
- liver function
- kidney function
- thyroid function
- haemoglobin A1c (to check for diabetes)
- vitamin B12 and folate levels
- urine test
Dementia brain scans
Brain scans are often used for diagnosing dementia once the simpler tests have ruled out other problems. Memory tests on their own brain scans can’t diagnose dementia, but are used as part of the wider assessment.
An MRI scan is recommended to:
- help confirm a diagnosis of dementia and the type of disease causing the dementia
- provide detailed information about the blood vessel damage that occurs in vascular dementia
- show shrinkage in specific areas of the brain – for example, the frontal and temporal lobes are mainly affected by shrinkage in frontotemporal dementia, while usually just the temporal lobes are affected in the early stages of Alzheimer’s
A CT scan can be used to check for signs of stroke or a brain tumour. But it can’t provide detailed information about the structure of the brain.
Even if a brain scan doesn’t show any obvious changes, this doesn’t mean someone doesn’t have dementia.
Other scans to diagnose dementia
Other types of scan, such as a PET scan, may be recommended if the result of your MRI or CT scan is uncertain.
Drug Treatments for Alzheimer’s disease
Acetylcholinesterase Inhibitors and Memantine are licensed for mild-to-moderate dementia but can be also be used to treat severe dementia if they are deemed helpful.