Dementia vs Delirium: Drawing the Fine Line

With very similar characteristics, many people tend to confuse dementia and delirium. Especially when it comes to diagnosing a person who is showing signs of these two mental conditions, you must pay attention to their differences in order to get the correct diagnosis and avoid risk factors.

As someone caring for an aging family member, it’s best that you know how to help them meet the needed care at the onset using correct information according to his state of health. 

What is the main difference between dementia and delirium?

What is the main difference between dementia and delirium Dementia Vs Delirium | My Delta Care

The evident difference between delirium and dementia are manifested in their effects: delirium’s effects fluctuate while dementia’s progress.

Acute confusional state or delirium is a disturbance in the mental state or status (or an altered consciousness) that results in confused thinking and reduced awareness of the environment. As such, it mostly affects attention. Delirium often starts rapidly — within hours or a few days. The risk is that it has a fluctuating effect on its victims, meaning that they will feel worse at a certain point and be better in a few minutes or hours.

Dementia is a general term that describes a long term loss in thinking ability, memory, and other mental abilities. It mostly affects memory. It’s a progressive disease that only worsens. It will also last for months, even years, which means that their conditions will only worsen as victims grow older. 

Causes of Dementia and Delirium

Dementia is not a disease itself. Instead, it is a group of effects of anatomic changes from different health conditions. The most well-known and perhaps the primary cause of dementia is Alzheimer s disease

A significant number of cases of dementia also root from Parkinson s diseaseHuntington’s disease, and multiple sclerosis. Another type of dementia is Lewy body dementia. This type involves progressive dementia that causes visual hallucinations and a change in alertness.

On the other hand, delirium occurs when the regular sending and receiving of signals in the brain worsen. 

The impairment is highly-likely caused by a combination of factors that make the brain vulnerable and trigger a malfunction in brain activity. 

Delirium may have a single cause or more than one cause, such as a combination of a medical condition and drug toxicity. Sometimes no cause can be identified. 

Delirium and Dementia: Comparing the Symptoms

A person can often get confused between delirium and dementia because of their symptoms. The mentioned conditions have very similar effects.

Symptoms of delirium may typically begin within a few hours or a few days. Delirium will tend to worsen during the night or when it’s dark and things look less familiar.

Some signs of delirium include:

Delirium and Dementia: Comparing the Symptoms Dementia Vs Delirium | My Delta Care

Delirium is not chronic, though. It is usually temporary.

Signs of dementia are similar to delirium, but they do not fluctuate. Instead, they progress and get worse over time, hence chronic.

The symptoms of a dementia patient may include: 

All these may start out mild, but eventually could worsen, especially if not addressed properly.

In the event that a person has dementia, they are at increased risk of delirium and may experience signs from both. A link can be found between both events through their common symptoms and causes. Women, however, have more of a risk than men with both health issues. 


Dementia, delirium, and sometimes even depression, may be very similar, but knowing the differences between delirium and dementia at the onset help healthcare professionals (doctor, nurse, and other care staff) to support a person with these health issues and provide the best care service. As such, a person or patient, especially older people, who change because of a diagnosis of delirium instead of dementia are given drugs and complementary therapies accordingly.

If you are caring for a senior who shows signs of the two, seeking medical help early on and addressing needs right away always matter.

Browse through helpful reads here. This site features blog content for senior living and caring for the aged. 

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