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Can you die from dementia?

Some people may find the content of this page upsetting and difficult to think about. For more general information about how dementia progresses, see the progression and stages of dementia.

How do people die from dementia?

Dementia isn’t a direct cause of death in the same way that a fatal stroke or heart attack is. It doesn’t happen suddenly. But it does rob people of years of life that they would have been able to enjoy if they didn’t have dementia.  

If you’re 80 when you get diagnosed, research suggests that dementia tends to shorten your life by around 3 to 4 years, on average. At 65, it could take up to 13 years.

Dementia is progressive, which means that its symptoms get worse over time. A person with advanced dementia needs constant care to help with basic tasks like washing, dressing, eating, drinking and going to the toilet.

Over time a person with dementia becomes increasingly frail, which makes them less able to recover from injuries and illnesses.  

In the very advanced stages of dementia, a person may spend much of the time sleeping in bed, moving, eating and drinking very little. This makes them susceptible to infections like pneumonia, urinary tract infections and pressure ulcers. When someone is very frail, these can be difficult to treat or recover from fully.

Eventually, something happens that they can’t recover from, such as an infection, stroke or heart attack. These are often the direct causes of death, but advanced dementia is what brought them to such a state of extreme vulnerability.

What do people with dementia most often die from?

There is no single pattern that applies to everyone who has dementia. The cause of a person’s death depends on the type and stage of dementia, their overall health, and whether they live at home, in a care home, or spend a long time in hospital.

The most common direct causes of death in people with dementia include:

• Pneumonia and other chest infections
• Other infections, such as urinary tract infections or sepsis
• Cardiovascular events, including heart attack and stroke
• Complications of frailty, such as dehydration, malnutrition, falls and pressure sores.

Frailty

Frailty is when the body has a reduced capacity to cope when things go wrong, such as an injury or infection. When a person who isn’t frail gets an infection, they tend to feel unwell for a few days or weeks and then recover fully – sometimes with the help of medicines or other treatment. For someone with frailty, the same infection may be life-threatening because their immune system is much weaker, their organs cannot handle the extra demands of fighting the infection, and treatments may not be as effective.  

Dementia causes this kind of frailty – not so much at first, but generally after several years or more of living with the condition. It can happen sooner though if someone is already very old or unwell before they get dementia, which is why people who get dementia in their mid-80s tend to die from it sooner than someone in their 60s or 70s.  

Younger people who are otherwise quite fit and healthy when they get dementia tend to take a lot longer to become so frail. 

Eating and swallowing problems

One of the main causes of frailty in dementia is people eating and drinking less as their condition progresses. Dementia can make eating and drinking difficult in several ways. Part of it is because of a severe loss of memory and thinking skills – for example, a person may not recognise food, they may forget how to use cutlery, or have trouble bringing food to their mouth. They may forget or lack the motivation to eat or drink unless they’re prompted, encouraged and helped to do so by a carer.  

Then there is the more physical side of advanced dementia. This is where the diseases that cause dementia damage the parts of the brain needed to coordinate chewing, swallowing and producing saliva. When these don’t work properly it can cause choking, which is both distressing and dangerous.  

Once choking becomes a problem, a person with advanced dementia may need to eat food that has a modified texture to reduce the risk of choking, such as blended or pureed foods. These are much less enjoyable than real food, which then makes it more difficult to encourage the person to eat enough. Drinks also need to be modified with thickeners to prevent choking, which makes drinking much less enjoyable too. It can then become very challenging to prevent weight loss and dehydration, which leads to more severe frailty and greater susceptibility to infections.

Swallowing problems also matter because food, drink or saliva can end up getting into the airway and lungs, instead of the stomach. This can happen without any obvious signs of choking. If germs on the food or saliva are carried into the lungs, this can cause ‘aspiration pneumonia’, which is a common cause of death for people with dementia. 

Infections and pneumonia

Pneumonia is one of the most common final illnesses in people with dementia. It may happen when people accidentally inhale their food, drink or saliva (known as aspiration) but it can also happen because the person is frail, less mobile and less able to cough effectively or clear their secretions.  

In advanced dementia, pneumonia is often the illness that directly leads to death.

Other infections are also common, including urinary tract infections and infected pressure sores. These can become serious because people with advanced dementia are often dehydrated, undernourished, incontinent or unable to move by themselves. In some cases, infection can lead to sepsis, which is a life-threatening response to infection.

Heart attacks, strokes and other cardiovascular events

Not every death in a person with dementia is caused by infection. People with dementia often have poor health and circulation problems, which means that they’re more likely to have a heart attack or fatal stroke. 

It can be hard to say how much dementia is contributing to a person’s death when this happens. However, we do know that people with dementia are less likely to seek help when they have a medical emergency or have their symptoms recognised. As a result, treatment may arrive too late or not at all.  

Frailty caused by advanced dementia can also make these events much more fatal than they would have been if the person didn’t have dementia. Treatments may also be less effective – for example, having heart surgery to clear a blocked artery may not be possible for someone with dementia because of the risks of severe complications and greater difficulty recovering from it. 

Why do some people die ‘from’ dementia and others ‘with’ dementia?

A person may die ‘from’ dementia when the condition begins a chain of events that leads to them dying earlier than they would have done otherwise. They may die ‘with’ dementia if another condition, such as cancer, is the main cause.  

However, in practice this boundary is often blurred because dementia makes other illnesses, such as cancer, much harder to treat and survive. A person with dementia will be more frail and may not be able to cope with aggressive cancer treatments, such as chemotherapy, radiotherapy or surgery. They will therefore have more conservative treatments that provide comfort rather than prolong life. 

Planning ahead with dementia

Because dementia is progressive, planning ahead can make a real difference. It allows the person to say what matters to them while they still can. It allows them to say what treatments they would or would not want, and where they would prefer to be cared for. This could include making an advance decision or advance statement.

Advance care planning is about making sure that any healthcare in the future is guided by the person’s values and preferences once they no longer have the mental capacity to make these decisions for themselves. It can also make a big difference in reducing distress for families and carers.