DLB shares some of the mental symptoms of Alzheimer’s disease and the
motor symptoms of Parkinson’s. But,
despite these similarities, the exact symptoms and damage caused to the brain
differ slightly in DLB. This overlap in
symptoms sometimes leads to misdiagnosis, so it is crucial to get an accurate
diagnosis to ensure effective treatment.
This is particularly important as those with DLB can be sensitive to
certain medications that may be used for other similar conditions.
One of the main symptoms of DLB is hallucinations, which occur in
approximately 80% of people with this type of dementia. These may be vivid and can cause irrational
behaviour. But, whilst they may be
distressing to carers, the person hallucinating is often not distressed, in
which case medical intervention may not be necessary.
The other symptoms of DLB are varied.
Some of the most common are:
- poor memory
- language problems
- poor concentration
- confusion
- visual hallucinations,
often involving children and/or animals
- difficulty recognising familiar faces and objects
- difficulty in carrying out simple everyday tasks
- difficulty with spatial awareness
- falls
- depression
- behavioural disturbances
- disrupted sleep pattern and possibly nightmares
- slowness of movement, stiffness, tremor and facial
masking.
DLB is a progressive illness so symptoms tend to gradually worsen until
they can affect daily activities and quality of life. There can be quite marked fluctuations in
attentiveness and alertness from hour-to-hour, day-to-day or even from month-to-month,
which can make it more difficult to diagnose and can be frustrating for family
and carers.
There are no specific tests for DLB.
Instead diagnosis is based on a detailed medical history and a full
examination by an experienced doctor. He
or she will ask about when symptoms occur and how long they last, and they will
also carry out some cognitive tests to assess the degree of difficulty with
thinking and cognitive processes.
As symptoms can fluctuate, several appointments may be needed and
periods of observation in order to reach a diagnosis. Key features that might lead to a confirmed
diagnosis are the presence of visual hallucinations, extreme and rapid
fluctuations in alertness and attention span, and the presence of motor
symptoms such as tremor, stiffness and slowness.
It is important that any other causes of dementia are ruled out, so
other tests, such as a brain scan to investigate stroke and blood tests may
also be conducted. Unfortunately a brain
scan may show degeneration of the brain but will not show the presence of Lewy bodies as these can only be detected during a post-mortem examination.
