Support for Caregivers of Older Adults
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Delirium (Acute Confusion)

 Overview    ↓ next top ↑
  • Delirium is common in older people.
  • Delirium has the following characteristics:
    • sudden onset and fluctuating course of confusion
    • inattention
    • disorganized thinking
    • altered level of consciousness
  • Delirium and dementia are similar, but different.
  • There are many causes of delirium.
  • Delirium is a medical emergency.
 Introduction    ↓ next top ↑
  • Delirium is quite common in older adults, affecting nearly one-third of those admitted to hospital.
  • Sometimes delirium accompanies a physical illness like pneumonia or a stroke. Other times, it is the first warning of a developing health problem.
  • Regardless of its cause, delirium is a serious medical condition – early recognition and treatment is essential.
 What You Should Know    ↓ next top ↑
 Characteristics of Delirium 

Delirium has the following features:
  • Acute onset and fluctuations – Confusion usually develops suddenly and progresses over the next few hours or days. The confusion fluctuates with periods of agitation and restlessness followed by periods of tiredness and indifference.
  • Impaired attention – The person has difficulty concentrating on familiar tasks, is not able to follow simple commands, or becomes more and more forgetful. They may not know what day it is, where they are, or even who they are. Thinking is confused. Speech may be slurred or jumbled.
  • Disorganized thinking – Unusual suspicions, paranoia, or hallucinations may occur.
  • Changes in level of consciousness
  • In hyperactive delirium, the person is agitated, with mood swings, at times angry, belligerent, and aggressive towards caregivers. For example, after surgery, they may try to climb out of bed, yell at caregivers, or pull out catheters and IV lines.
  • In hypoactive delirium, there is extreme drowsiness, fatigue, and indifference. As delirium fluctuates, the episodes of lethargy are followed by periods of agitation and hallucinations as in hyperactive state.
Delirium duration may range from a short episode to a few days (and even a few weeks or months), depending on the cause.
 Risk Factors    ↓ next top ↑

Individuals with the following characteristics are the most likely to have delirium:
  • advanced age
  • cognitive impairment or dementia (older people with dementia are especially susceptible to delirium)
  • history of previous episodes of delirium
  • multiple medical conditions
  • multiple medications
  • severe stress (from events like a move to a new environment, recent surgery or recent injury)
 Dementia and Delirium    ↓ next top ↑

Dementia and delirium share some common features and it is important to tell them apart. Dementia is a constant, slowly progressing loss of memory and function. On the other hand, delirium develops quickly. It is a warning of a serious underlying medical condition.
Differences Between Dementia and Delirium

Dementia Delirium
Onset and course slow onset over months or years sudden onset over hours or days
Speech normal slurred
Attention normal inattentive, easily distracted
Memory gradual memory loss more forgetful than usual
Hallucinations possible common
Mood normal or depressed anxious, fearful, suspicious, indifferent
General health usual sign of illness or drug side effect

 Causes of Delirium     ↓ next top ↑

Many medical conditions and other problems can lead to delirium. Remember this helpful hint – the letters in the word "DELIRIUM" stand for the common reasons for this condition.

Drugs many medications, recently started or stopped, changes in dosages, over-the-counter medications, herbals, alcohol
Electrolyte imbalance especially from dehydration
Lack of drugs stopping certain medications, alcohol withdrawal
Infection such as urinary or respiratory tract infections; blood or wound infection after an injury or surgery
Reduced sensory input such as poor or uncorrected vision and hearing
Intracranial such as from a stroke
Urinary or fecal problems such as inability to empty bladder or bowel
Myocardial (heart) and lungs heart attack, pneumonia, or other condition causing lack of oxygen in the blood and the brain

 When Medical Attention Is Needed    ↓ next top ↑

Early detection and treatment is essential because delirium is a sign of a serious underlying medical condition. In addition, older people with delirium are susceptible to injuries, falls, dehydration, pressure sores, and malnutrition.

Delirium is a medical emergency. Accompany your family member to the emergency department, and be ready to provide information on:
  • past medical problems
  • current medication list
  • details of everyday functioning and thinking before the confusion
 See Also    ↓ next top ↑

While the content of each Caregiver College Topic may be linked to a variety of other Topic areas, the following has been identified as a Key Linkage which you may be interested in also reviewing:
 Resources  top ↑

Capital Health
  • Information for Patients and Families – Delirium: This PDF document from Capital Health's Regional Specilized Geriatrics Program provides information about the causes and treatment of delirium. It also describes how family members can help with treatment and communicate with both a confused older person and a health care provider.
Merck Source
  • Merck Manuals: Merck Manuals provides information about delirium, including its causes, symptoms, treatment and diagnosis. It also contains tables to assist you in comparing delirium with dementia and psychosis.
  • Active HealthMap – Delirium: This flowchart facilitates easy access to detailed information on diseases, condition progression, therapeutic options and outcomes. The information is organized by topic and is contained in the Merck Manual Home Edition.
Selfhelp Magazine
  • A brief article on dementia versus delirium.
Canadian Mental Health Association
  • Canadian Mental Health Association website page titled Seniors and Delirium. Information specific to seniors and delirium is presented.
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