Bruce Willis diagnosed with dementia: 5 types of the illness to know

SINGAPORE Dementia, a generic term for the impaired ability to remember, think, or make decisions about everyday activities, has been in the spotlight since Thursday, after the family of US actor Bruce Willis announced that he was diagnosed with frontotemporal dementia.

Around one in 10 people aged 60 and above in Singapore suffers from dementia, according to the Ministry of Health. There are over 100 forms of dementia, according to the Alzheimers Disease International, each with different causes and symptoms.

Here are five common types of dementia. 1. Alzheimers disease

According to the World Health Organisation (WHO), this disease contributes to 60 to 70 per cent of dementia cases worldwide.

The condition is caused by a build-up of certain kinds of proteins in and around brain cells. Such a build-up causes a decrease in chemical messengers that send messages, or signals, between brain cells.

Over time, various areas of the brain start to shrink and the first area usually affected is ones memories.

A progressive disease, Alzheimers leads gradually to worsening symptoms over the years, causing memory loss and affecting thinking skills that lead to the loss of ones ability to respond to people and surroundings, and to perform simple tasks such as eating and bathing.

On average, those who suffer from this disease have a life expectancy of between eight and 10 years after diagnosis. 2. Vascular dementia

According to John Hopkins Medicine, this is second-most common form of dementia worldwide, after Alzheimers disease.

It is caused by poor blood flow or injury to blood vessels in the brain, mostly because of strokes. Depending on the size and location of the area affected, one may either become forgetful, or, in serious cases, have trouble thinking clearly and significant memory problems that disallow one to function normally.

Heart diseases and atherosclerosis (hardening of the arteries) also raise the risk of one contracting vascular dementia. More On This Topic US action star Bruce Willis diagnosed with dementia Meet the people banding together to build dementia-friendly communities in Singapore According to Singapores DementiaHub website, treating and controlling the risk factors, such as high blood pressure, diabetes, high cholesterol and smoking, may help slow its progression and reduce stroke recurrence.

The lifespan for someone with this form of dementia is around five years after diagnosis as one is more likely to die from a stroke or a heart attack than from the disease itself, reported the Alzheimers Society. 3. Lewy body dementia (LBD)

This type of dementia occurs when there is an unusual build-up of structures called Lewy bodies inside ones brain cells, said DementiaHub.

Lewy bodies affect specific areas of the brain, resulting in memory, thinking, movement and behavioural issues.

Diagnosing this form of dementia can be challenging due to its similar symptoms with other diseases such as Alzheimers, Parkinsons disease and schizophrenia, said the Lewy Body Dementia Resource Center.

Symptoms can include slowness, tremors, rigid muscles and vivid visual hallucinations. Those diagnosed with Lewy Body dementia could fall more often due to their increased rigidity, instability and slow gait.

Their life expectancy is about six years after diagnosis as the disease increases a persons risk of falls and infections. 4. Frontotemporal dementia

This is the type of dementia that Willis was diagnosed with.

According to John Hopkins Medicine, this form of dementia occurs when ones nerve cells in the frontal and temporal lobes of the brain are lost, causing the lobes to shrink.

After the lobes have shrunk, a person with this disease may experience significant changes in personality, behaviour and emotion, as well as language difficulties.

The life expectancy for someone diagnosed with this form of dementia is about six to eight years. More On This Topic Interactive: How a loving son created a dementia-friendly home for his dad Dementia Singapore taps OneService app to help families find loved ones who go missing 5. Mixed dementia

According to Alzheimers Society, mixed dementia is a condition where a person has more than one type of dementia. The most common mix is the Alzheimers disease and vascular dementia. In some cases, a person may get all three conditions Alzheimers disease, vascular dementia and LBD.

Depending on which part of ones brain is affected, the symptoms vary. In some, they are often similar or identical to Alzheimers or other types of dementia. In others, ones many symptoms may indicate that there are more than one type of dementia present.

The life expectancy of this type of dementia is unclear. Other diseases that lead to dementia

Besides the five common types of dementia mentioned, other illnesses, such as Parkinsons disease, Huntingtons disease, and Creutzfeldt-Jakob disease, also cause one to develop dementia as part of their symptoms.

Rarer forms of dementia include the Wernicke-Korsakoff syndrome and posterior cortical atrophy.

The former is a condition caused by drinking excessive alcohol over a prolonged period of time, while the latter is due to the degeneration of the cells at the back of the brain that first causes eyesight problems.

Although dementia itself is not inherently life-threatening, it can lead to an increased risk in other serious illnesses such as pneumonia, infections and fall-related injuries. More On This Topic People with dementia, caregivers get more support in action plan for successful ageing When grandpa cant find his way home: How to help those with dementia