What are the main types of dementia? As new technique could ‘revolutionise’ how disease is diagnosed

Excitement is building as a new test involving lasers used to detect different types of dementia in mere seconds could “revolutionise” the way the disease is diagnosed.

Researchers at the University Hospital Southampton and the University of Southampton are leading a study that analyses bodily fluids such as blood, spinal fluid or mucus using lasers to identify people with dementia early in the disease.

Dementia can take up to two years to diagnose, but researchers say that this new laser-based technique is much quicker and cheaper.

But what are the most common types of dementia, and how do they differ?

Alzheimer’s disease

“It is caused by a build-up of proteins in the brain which affect how the brain cells transmit messages,” explains Fay Valentine, admiral nurse at Dementia UK. “As time passes, more and more brain cells are damaged, leading to worsening symptoms.”

Symptoms of Alzheimer’s are usually mild at the beginning and gradually worsen over time.

“People can experience issues with memory, concentration and speech; this can all culminate in the person withdrawing from social and family circles,” says Valentine.

Age is the biggest risk factor for developing Alzheimer’s disease.

“It affects one in 14 people over the age of 65, and one in six people over the age of 80,” says Valentine. “Other risk factors include smoking, obesity and diabetes.”

Furthermore, there isn’t a single definitive test for Alzheimer’s.

“The diagnosis is based on a combination of tests and assessments which can take time,” explains Valentine. “The GP will first rule out any other medical condition that might be causing the person’s symptoms.”

There’s currently no cure, but medicine, such as acetylcholinesterase inhibitors and memantine, can temporarily reduce the symptoms.

Vascular dementia

Vascular dementia is the second most common type of dementia.

“It is a form of dementia that occurs when the brain does not receive enough blood supply, meaning it cannot carry out its normal functions,” explains Valentine. “It can cause problems with concentration, thinking and carrying out daily activities.

“The early symptoms of vascular dementia also differ from some other types – for example, changes in mood, behaviour and personality are initially more common than memory problems.”

Vascular dementia progresses at different rates for different people.

“The onset is often gradual, although in some cases – for example, if the person has a stroke – it may be sudden,” highlights Valentine.

The diagnosis of vascular dementia is based on a combination of tests and assessments, referred by your GP to memory services after they have ruled out other medical conditions.

“There are no specific treatments for vascular dementia, however medications may be prescribed to reduce the risk of further stokes occurring, or to treat underlying physical health conditions,” adds Valentine.

Lewy body dementia

“Lewy body dementia is a progressive, complex and challenging condition which is thought to account for 10-15% of all those with dementia,” says Valentine. “It includes two subtypes; dementia with Lewy bodies and Parkinson’s.

“It particularly affects the person’s ability to think and move and can cause hallucinations, fluctuations in alertness and sleep disturbances which can be extremely distressing for the person and their family.”She explained that this less-common type of dementia is caused by abnormal clumps of protein (called Lewy bodies) gathering inside brain cells.

“These Lewy bodies can build up in many parts of the brain but particularly in the areas responsible for thought, movement, visual perception and regulating sleep and alertness,” highlights Valentine.

The nurse also stressed the importance of an accurate diagnosis, as she noted that it is often mistaken for Alzheimer’s in its early stages.

“Diagnosis should include gathering information on the person’s symptoms and a SPECT scan,” says Valentine.

Treatments to ease the symptoms include speech, physio, occupational and psychological therapies and medicines to reduce hallucinations, confusion, drowsiness, movement problems and disturbed sleep.

Frontotemporal dementia

“Frontotemporal dementia (FTD) is an umbrella term for a group of dementias that mainly affect the frontal and temporal lobes of the brain, which are responsible for personality, behaviour, language and speech,” explains Valentine. ”Unlike other types of dementia, memory loss and concentration problems are less common in the early stages.

“Symptoms can include reduced motivation, lack of interest in things the person used to enjoy, and inappropriate behaviour.”

An abnormal build-up of proteins within the brain which damages the cells causes FTD, explains the nurse.

“It is not known why this occurs, but it is thought to have a genetic link in about one third of people with the diagnosis,” adds Valentine.

It is important to contact a GP as soon as any concerns arise.

“If they need further investigations, the GP should refer them to a specialist for a comprehensive assessment of attention, memory, fluency, language, visuospatial abilities and behaviour changes,” says Valentine.

Treatments for symptoms include therapies, dementia activities and medicines.