Vascular dementia is the second most common type of dementia after Alzheimer’s disease, and affects around 150,000 people in the UK.

But very few people know exactly what it is or how it differs from other forms of dementia – and this ignorance can perpetuate a sense of fear, especially for an ageing population.

However, a storyline in Emmerdale has brought it to the nation's attention. Vicar Ashley Thomas suffer from vascular dementia, and playing the character, actor John Middleton has said filming his dementia scenes has been like “watching someone diminish”.

And as the storyline comes to a head, John recently told The Radtio Times: “My hope is that Emmerdale has at least been able to embed the issue of dementia into the public’s consciousness.

“We’re all guilty of looking the other way, but we ignore this at our cost. It could well happen to each and every one of us.

“It’s possible that we could find a cure, but we need more money going into research to turn that possibility into a probability.

“The good news is that we’re all living longer, but because of that, we’re more likely to die of this disease. And there’s no point in living longer if we can’t live well.”

To try and alleviate the anxiety, we get back to the basics.

What is vascular dementia?

The word dementia describes a set of symptoms that can include memory loss and difficulties with thinking, problem-solving or language. In vascular dementia, these symptoms occur “when there is a reduced blood supply to the brain due to diseased blood vessels,” explains Kathryn Smith, director of operations at Alzheimer’s Society.

[Read more: Emmerdale's John Middleton opens up about dementia storyline]

To be healthy and function properly, brain cells need a constant supply of blood, which is delivered through a network of vessels called the vascular system. If the blood vessels leak or become blocked, then blood can’t reach the brain cells and they’ll eventually die. It’s the death of brain cells which causes problems with memory, thinking or reasoning (collectively known as cognition). When these cognitive problems are bad enough to have a significant impact on daily life, it’s known as vascular dementia.

Who gets vascular dementia?

There are a number of factors that put someone at risk of developing vascular dementia, including:

Age

The risk of developing the condition doubles approximately every five years over the age of 65.

History of cardiovascular disease 

A person who’s had a stroke, or has diabetes or heart disease, is approximately twice as likely to develop vascular dementia.

Sleep apnoea

A condition where breathing stops for a few seconds or minutes during sleep is a possible risk factor.

Depression

According to the Alzheimer’s Society, there is some evidence that a history of depression also increases the risk of vascular dementia.

Genetic factors

Someone with a family history of stroke, heart disease or diabetes has an increased risk of developing these conditions, although the role of genes in the common types of vascular dementia is small.

Can I reduce the risk?

Cardiovascular disease, and therefore vascular dementia, is linked to high blood pressure, high cholesterol and being overweight in mid-life, so someone can reduce their risk by having regular check-ups, not smoking, and keeping physically active. It also helps to eat a healthy balanced diet and drink alcohol in moderation.

Aside from these cardiovascular risk factors, there is evidence that keeping mentally and socially active throughout life reduces dementia risk, too.

What are the symptoms of vascular dementia?

“The most common symptoms in the early stages of vascular dementia are problems with planning or organising, problems making decisions or solving problems, slower speed of thought and having problems concentrating – including short periods of sudden confusion,” Smith explains.

As well as these cognitive symptoms, it is common for someone with early vascular dementia to experience mood changes, such as apathy, depression or anxiety. But symptoms will be dependent on the underlying causes. For instance, symptoms may develop suddenly after a stroke, or more gradually, such as with small vessel disease.

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Will someone deteriorate quickly?

Over time, a person with vascular dementia is likely to develop more severe confusion or disorientation, and further problems with reasoning and communication. Memory loss – for example, around names or recent events – will also become worse. Over time, the person is likely to need more support with day-to-day activities such as cooking or cleaning as they become increasingly frail. The speed and pattern of this decline varies, but on average someone lives for about five years after the symptoms start, and is most likely to die from a stroke or heart attack.

Is there a cure?

In a word, no. “There is currently no cure for vascular dementia,” says Smith. “The brain damage that causes it cannot be reversed.

“However, there is a lot that can be done to enable someone to live well with the condition. This will involve drug and non-drug treatment, support and activities.”

The person should have a chance to talk to a health or social care professional about their dementia diagnosis. This could be a psychiatrist or mental health nurse, a clinical psychologist, occupational therapist or GP.

Anyone who is concerned that they may have vascular dementia (or any other type of dementia) should seek help from their GP.

For more information visit www.alzheimers.org.uk.