Dementia and Delirium

Dementia Aware: what you need to know about delirium in the person with dementia


Delirium is a serious illness and can be experienced by anyone, at any age. However, the senior population are more susceptible to delirium and it is estimated that approximately 30-40% of most people with dementia will experience an episode of delirium. Delirium is a sudden and noticeable change in the person with dementia’s mental state. For example, the person with dementia may appear more confused than usual, or may display unusual or new behaviours, or may suddenly experience hallucinations and/or delusions. The challenge is that many caregivers can miss the onset of delirium. They will notice the person with dementia is different, but may think it is because he/she did not sleep well, or is just having a bad day. This may be true, no one knows the person with dementia better than the caregiver; unfortunately, delirium is a medical emergency, and if left untreated, can lead to permanent problems, and in some cases, it can lead to death. Delirium also increases the chance that a person with dementia, especially in the middle to late stage of dementia, will require a higher level of care.


The most common causes of delirium include:

  • Infection e.g. bladder infection (UTI), pneumonia
  • Constipation, fecal impaction
  • Urine retention
  • Traumatic event e.g. fall, fracture
  • Hyperglycemia (very high blood sugar)
  • Hyperthermia (high body temperature)
  • Alcohol withdrawal
  • Severe pain
  • Reaction to medications
  • Anaesthesia
  • Hypoxia (decreased oxygen to the brain) caused by a stroke or a seizure


It is important to remember that delirium is a change from the person with dementia’s ‘usual’ state. It also develops over a short period (usually hours to days), often fluctuates throughout the day and is often worse at night. To help determine if the person with dementia has a possible delirium, the caregiver should consider the following questions.


Is the person with dementia:

  • More sleepy and quiet than usual OR more restless and agitated?
  • More confused?
  • Seeing things or hearing voices (hallucinations)?
  • Pacing or have sudden difficulty walking?
  • Having outbursts of anger OR is sad and tearful, OR fearful and anxious OR appears euphoric?
  • Suddenly paranoid?
  • Switching back and forth from hyperactive to hypoactive behaviour?
  • Having difficulty reading or writing and/or paying attention?
  • Believes things that are not true (delusions)?
  • Talking gibberish, calling out or ranting?

If you answered YES to any of the signs above, the person with dementia may have delirium and you should contact your family doctor immediately, or call 911.


How to avoid possible delirium:

  • Drink fluids esp. water, throughout the day. In warm weather, fluid intake should increase (dementia can cause a decreased thirst mechanism)
  • Eat regular meals
  • Manage diabetes
  • See your Doctor regularly for a medication review e.g. in the middle stage of dementia, BP can fall due to dementia related weight loss and changes in cardiac output
  • Monitor urine output for any changes: no urine output, bleeding, discharge or unusual odour
  • Wear clothing appropriate for the weather: hat on sunny days, coat and hat on cold days. (As we age, we lose the ability to perspire and regulate our body temperature and we become more vulnerable to cold and heat. Dementia can inhibit a person’s sensory ability to feel hot and cold)
  • Prevent constipation (diet, fluids, exercise). Talk to your doctor if you need laxatives
  • Make the home environment safe to reduce risk of falls and injury: non slip bath mat, lighting


If medical attention is sought quickly, delirium can be treated and most people with dementia usually get better over a few days to a few weeks. For others, it may take up to 1 year for the delirium to clear. Unfortunately, in the person with dementia, delirium can result in a worsening of the person’s cognitive function. For example, the person may no longer be able to do tasks he/she could do before the onset of delirium, such as dressing or bathing or walking independently. However, on a positive note, studies indicate that the risk of delirium in people with dementia can be significantly reduced if they and their caregivers implement strategies to reduce the risk of delirium and know when to seek medical attention.


Tracey Maxfield is a dementia consultant and advocate with over 35 yrs. experience working with dementia populations in the U.K. and Canada. She is presently lobbying the Federal and Provincial Governments and local municipalities to respond to the dementia crisis in B.C., especially in the Okanagan. She can be reached @

Related Articles

Is it Really Dementia?

Dementia Aware: what you need to know about conditions mistaken for dementia You misplace items, you forget to take your medications, you feel tired and weak, you cannot remember what you did five days ago. You are scared and anxious, but will not see your Physician because you are worried

Read More »

Interview with Carleen Johnson, KOMO 4 News Radio Show Anchor

RADIO SCRIPT:   Tracey, My pleasure to interview you. What a beautifully real message you are sharing with the world. I pray you’ll be blessed by your willingness to open up in this public way! Carleen Escaping the Rabbit Hole is the name of Tracey Maxfield’s book…a compilation of the

Read More »

Exploring Awesome with Jim Keller and Tracey Maxfield Part 2

Read More »