Dementia and Delirium: 5 Key Differences

dementia and deliriumYou visit Dad in the hospital, and he asks you why he’s in a flower garden. You’re trying to talk
to Mom, but she can’t follow the flow of conversation. If your parent is over sixty-five, you may wonder if you’re seeing the onset of Alzheimer’s or some other form of dementia.

However, that’s unlikely. Dementia progresse will s slowly. If you see a sudden change in an older person’s mental or emotional state, it’s more likely to be delirium.

It’s important to know the difference: dementia is a chronic condition.

Delirium, however, is a medical emergency.

What’s the difference between dementia and delirium? Here are 5 ways to tell:

1. Onset

Dementia begins slowly, usually with memory loss. It generally takes time to recognize a pattern to the loss of function.

Delirium has a sudden onset. Someone with delirium might be functioning properly one moment, and then suddenly start hallucinating.

2. Duration

Dementia is a chronic disease. Other than in the unusual cases in which it is brought on by other conditions, it is incurable. It is also progressive, meaning that cognitive function will continue to degrade.

Delirium is an acute state, meaning not only that its onset is abrupt, but that its duration is short — assuming proper treatment is administered. Without prompt, proper treatment, it can have severe repercussions.

3. Causation

Dementia is usually caused by a neurodegenerative disease: a disease that causes the death of brain cells.
It can also be caused by other insults to the brain, such as a stroke, a tumor, or a head injury.

Delirium is usually triggered by some other acute cause.
This cause may be an infection, such as a urinary tract infection or pneumonia.
Particularly in the elderly, the cause may be a relatively minor medical issue, such as constipation, dehydration, or sleep deprivation.
A change in environment, particularly a move into an environment that is completely unfamiliar, such as a hospital, is such a common cause of delirium in older people that it even has its own name: hospital- or ICU-psychosis.
Medication interactions, as well as illicit drug use or withdrawal from alcohol or illicit drugs can also cause delirium.

4. Symptoms

Dementia is marked by loss of memory, and memory loss is usually the first symptom to appear.
Finding the right words becomes increasingly difficult, and the person may start to have difficulty completing normal, every day tasks, such as cooking.
A person with dementia may become easily lost, even in familiar environments; and may start misplacing everyday items, such as their keys.
As the disease progresses, the symptoms worsen; communication and abstract thinking become difficult or impossible, and the person may develop changes in personality and mood.

Delirium, on the other hand, does not generally involve any memory issues.
Rather, the personality and mood changes common in late-stage dementia appear abruptly.
The person may be unable to speak coherently; they may hallucinate; and they may become
either hyperactive or unresponsive.

5. Treatment

Dementia has no cure, but there are many treatments to slow the progression of symptoms.

Delirium, if caused by an infection or other illness, will resolve when that illness is addressed.
The most important issue with delirium is that it be identified as soon as possible, so that
it can be treated.
Untreated, it not only causes significant distress to the person (and their loved ones),
but it can also lead to other complications, including dementia, or even death.

At Hamilton Grove Healthcare and Rehabilitation, our caregivers are specially trained to note changes in resident’s behavior. Our staff, from our physicians to our dietitians, create every resident’s personalized plan with an eye toward maintaining optimal physical and mental health.

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