Jul 3, 2017

Dementia or Delirium - Which one is it?

Families should not automatically think that their loved one has taken a huge nosedive in memory. Sometimes it’s delirium, instead of dementia.

How do you tell the difference between Dementia and Delirium?
By Carole Larkin
Alzheimer's Reading Room

Not long ago I attended a wonderful lecture on delirium by Dr. Vivyenne Roche of the University of Texas Southwestern Medical School.

I am going to give you some facts and statistics from her lecture and then try to help caregivers use that information in their own lives and the lives of their loved ones.

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What is the difference between Delirium and Dementia?

  • Delirium mainly affects attention.
  • Dementia mainly affects memory.

What is Delirium?

Delirium is defined as the change of a person’s mental status from what it was before. It is temporary, meaning that there is an end to it, not like a dementia which has no end to it (except death).

Delirium can go on for hours, days, weeks, even months, but eventually the person returns to their former cognitive state.
  • 25 percent of persons with delirium still have it one month after leaving the hospital and 18 percent still had delirium 6 months after leaving the hospital! Delirium can fluctuate (be stronger or weaker or change subtype) even during a single day.
There are two subtypes of delirium.

The first is the hyperactive type we think of when hearing the word delirium.
  • Symptoms are agitation, hallucinations, inappropriate words or behavior, among other symptoms. Between 22 and 30 percent of people have this type of delirium.
Another sub type is the hypo-active type, which looks very much like depression or even dementia of the Alzheimer’s type.
  • The symptoms are lethargy and hyper somnolence (excessive sleeping). Between 24 and 26 percent have this type of delirium. Some people actually show both types within a day’s time and it is called mixed delirium. Between 42 and 46 percent have the mixed type.
Delirium usually shows up at the time of hospitalization, although 40 percent of elderly patients come into the hospital already delirious.

Of those not already delirious upon admission, another 5 to 35 percent go on to develop it while in the hospital.

There is a high occurrence of delirium in patients who have had operations, especially orthopedic operations like spine operations and knee replacements (65 percent!).
  • Nursing home patients over the age of 75 who are brought to the hospital for any reason have delirium at the rate of about 60 percent. 
What is termed “terminal delirium”, that is, delirium which is followed by death, happens in 25 to 85 percent of patients.

How is Delirium Diagnosed?

Here is the really scary part.

  • Physicians directly involved in the patient’s care miss diagnosing the delirium between 33 and 67 percent of the time.

Common ways of diagnosing delirium are: administering the Mini Mental State Examination (MMSE), doing a Digit Span Test, and asking the person to name the days of the week in backward order.

Individuals present the condition differently.

Sometimes the delirium is the only presentation of severe illness in older patients.
  • Sometimes the delirium means that the person has had a silent heart attack (up to 40% of patients with delirium). 
  • 25% of persons who have delirium associated with pneumonia, TB, endocarditis (inflammation of the sac that holds the heart) or sepsis (whole body infection) have no fever. 
  • 13% of older patients who have a bacterial infection have no fever.

Delirium is truly hard to diagnose


It would help if doctors always suspected it on admission into the hospital (in the emergency room) but many doctors don’t think about it.

What can be done to diagnose it is to do an immediate cognitive screening in the ER as a baseline to compare with later in the hospitalization, a medication review, run blood tests like CBC, Bun, Creatinine, glucose, calcium, phosphate, liver enzymes, blood alcohol, and ammonia levels.

Also an EKG (for abnormal heart rhythms) and/or an EEG (for abnormal brain activity).

Some risk factors influencing a higher rate of delirium in the elderly are:

  • Electrolyte abnormalities
  • Gastric disorders
  • Trauma (falls, fractures, pain)
  • Cognitive impairment (MMSE below 24)
  • Use of physical restraints in the hospital
  • Malnutrition
  • Use of a bladder catheter in the hospital
  • 3 medications added within a 24 hour period
The 3 most common reasons delirium happens are infection, metabolic disturbance and medications. 62% of people with a hip fracture had multiple reasons for having delirium.

How do doctors treat Delirium?

Basically there are two approaches to treatment and many times doctors turn to the pharmacological treatment before they consider the environmental types of treatment.

The pharmacologic treatment of choice is the drug Haldol. Haldol inhibits dopamine in the brain. Haldol is the drug that has been studied the most.

It sedates, treats hallucinations, paranoia and delusions and it is less detrimental to the dementia (in patients who have a form of dementia as well as delirium) and causes blood pressure to go up less than other drugs used for the same purposes. It works quickly and has a reasonable safety profile.

Its antipsychotic effects can last 3 to 6 days and it can be administered in a number of different ways.

Generally the starting dose is 0.5 mg. It can be repeated every half hour until the desired effect appears. The maximum dose should not be more than 5 mg within 24 hours. Some doctors add Lorazepam (Ativan), but adding it sometimes makes the delirium worse instead of better.

The second way is non pharmacological.

The hospital environment can be modified by :
  • using clocks and calendars to improve orientation to time and day,
  • opening the curtains to let natural light into their room,
  • making sure that they have their hearing aids and glasses and that they use them,
  • having family members there as much as possible,
  • asking the doctors and nurses to let them walk the hallways with an escort,
  • taking off any physical restraints on them,
  • removing catheters if not needed for urinary function, and
  • finally, having the person moved to a room next to the nurses’ station where they can keep an eye on him/her easily.
What lessons can families take away from this information on delirium?

Delirium before, during and after hospitalization is common.

In time it usually resolves on its own, but it may take weeks or months to do so.

Families should not automatically think that their loved one has taken a huge nosedive in memory right after leaving the hospital. Sometimes it’s the delirium, instead of dementia.

Give it time to see if your loved one comes back up a little. Maybe as much as several weeks to 6 months is the amount of time to wait. Don’t go trotting off to the doctor for more antipsychotics right away.

Haldol is NOT the answer to regular agitation!

Changing the environment around the person is the best answer.

That means changing your attitude to a positive one, changing your communication to emphasize the things they can do as opposed to the things they can’t do, adapting the physical environment to lower agitation like letting in natural light as much as possible, not using the TV as a babysitter all day (having them engaged with a person at times during the day), and simplifying what they see all around them (decluttering the area where they spend most of their time.

Articles Related to Delirium

Delirium and Urinary Tract Infection

Methods of Relieving Delirium In Dementia Patients

Delirium is a Strong Risk Factor for Dementia

Hospitals Stays Can Cause Delirium Worsen Alzheimer's

27 Ways to Take Care of a Dementia Patient in the Hospital


What to do when dementia patient gets agitated

How to talk to a parent with dementia

Alzheimer's Symptoms Stages

Care of Dementia Patients


Carole Larkin MA, CMC, CAEd, DCP, QDCS, EICS is an expert in Alzheimer’s and related dementia care. She is a Certified Geriatric Care Manager who specializes in helping families with Alzheimer’s and related issues. Carole can consults with families via telephone nationwide on problems related to the dementia. Her company, ThirdAge Services LLC, is located in Dallas, TX.

Dementia is a syndrome in which there is deterioration in memory, thinking, behavior and the ability to perform everyday activities.

Delirium (sometimes called acute confusional state) and dementia are the most common causes of cognitive impairment, although affective disorders (eg, depression) can also disrupt cognition. Delirium and dementia are separate disorders but are sometimes difficult to distinguish. In both, cognition is disordered; however, the following helps distinguish them:

Delirium affects mainly attention.
Dementia affects mainly memory.

~Mayo Clinic

Originally published in the Alzheimer's Reading Room August,2013