Delirium and dementia | Signs and symptoms

Delirium is an abrupt change in the brain’s ability to function. It can cause someone to become extremely confused, emotional or even to lose control of some of their muscles. Delirium is a temporary condition but can be severe while the person is experiencing it, particularly if they already live with dementia.

What are the signs and symptoms of delirium?

Symptoms of delirium come on suddenly, usually over a few hours or days. They can include:

• Disorientation and confusion
• Speech problems, such as slurring or the words coming out in the wrong order. The person may start talking nonsense, similar to how people do when they are not fully awake
• Being unaware or unengaged with what is going on around them. It may seem like they cannot properly hear or see you
• Mood swings and extreme moods, such as euphoria, depression or feeling terrified but you don’t know what of
• Becoming physically slow in movement and speech, seeming exhausted
• Hallucinations or extremely vivid dreams
• Paranoia

In somebody living with dementia, it may be more difficult to spot the signs of delirium because they are similar to the symptoms of dementia.

Types of delirium

The two main types of delirium are hyperactive and hypoactive. While the behaviours for these are often opposites, it is possible to experience both. Somebody with what is known as ‘mixed delirium’ can switch between experiencing hyperactive and hypoactive deliriums regularly.

Hyperactive delirium

Hyperactive delirium causes people to become very rushed and energised. They may become restless, talk rapidly and behave erratically. They may struggle to sleep.

Hypoactive delirium

In contrast, hypoactive delirium can cause people to become very slow and sluggish. They may move and speak very slowly and very little, and appear to find speaking or moving laborious. They may sleep much more than usual.

Delirium tremens

Delirium tremens happens to people suffering alcohol withdrawal. It can happen when somebody who is dependent on alcohol has no access to it or chooses to abstain. Delirium tremens (or DTs) can include becoming extremely confused, physically shaking, sweating, fainting and having heart palpitations. They might even have visual or auditory hallucinations.

How soon after the last drink the DTs set in, if at all, depends on the individual and how much alcohol they usually consume. Severe cases of the DTs can be fatal, so people going through alcohol withdrawal at this level often have to take medication to wean their body off the substance.

What causes delirium in somebody living with dementia?

Delirium can be caused by a number of factors that affect the chemical balance in the brain. These can include:

• Dehydration
• Nutritional deficiencies
• Sudden withdrawal from drugs, alcohol or medication, or a toxic amount of these substances
• Various infections
• Kidney or liver damage
• A brain injury or brain infection, such as encephalitis

If a person lives with dementia, they can be more prone to delirium through difficulties with staying hydrated and nourished, or infections going unnoticed due to communication difficulties.

How to spot delirium in somebody living with dementia

Delirium and dementia have similar symptoms, which is why you should always seek medical assessment if you suspect that you or a loved one has either of these conditions. The main differentiator is that symptoms of dementia come on gradually and progressively worsen, while symptoms of delirium begin quickly and can come and go. Delirium also primarily affects attention and concentration, while dementia, depending on the type, causes symptoms more related to memory.

Delirium and dementia can go hand in hand. Both are more common in older people. A person may have both conditions which impact on each other. For example, they may forget to drink because of their dementia, then suffer delirium as a result of dehydration, which in turn makes them more confused and forgetful.

Is there a cure for delirium?

Delirium is almost always a temporary problem. Usually it can be fixed by addressing the cause, such as rehydration, supplementation or treating an infection.

Sometimes people are prescribed antipsychotics, such as Haloperidol, to deal with their delirium.

How do I support a loved one who is suffering delirium?

The NHS recommends that you seek medical attention for anybody you may suspect is suffering with delirium. This could be a GP or, if you fear for their safety or they have a dangerously high heart rate, an ambulance.

When somebody is delirious, you should be careful not to confuse or agitate them more. Communicate by speaking clearly, asking simple questions, such as ‘Do you know where you are?’ and remaining calm. Focus on reassuring them that they are safe.