Delirium is a serious disturbance in a person's mental abilities that results in a decreased awareness of one's environment and confused thinking. The onset of delirium is usually sudden, often within hours or a few days.
Delirium can usually be traced to one or more contributing factors, such as a severe or chronic medical illness, medication, surgery, or drug or alcohol abuse.
The symptoms of delirium and dementia are similar, and input from a family member or caregiver may be important for a doctor to make a diagnosis.
Signs and symptoms of delirium usually appear in a short period of time, from a few hours to a few days. The symptoms often fluctuate throughout the day. Therefore, a person may have periods of no symptoms. The primary signs and symptoms of delirium include the following factors.
Reduced awareness of the environment
Cognitive impairment, or poor thinking skills
Other common symptoms
Delirium and dementia
Dementia is the progressive decline of memory and other thinking skills due to the gradual dysfunction and loss of brain cells. The most common cause of dementia is Alzheimer's disease.
Some common distinguishing differences between the symptoms of delirium and dementia include the following:
One type of dementia called Lewy body dementia is more difficult to distinguish from delirium because hallucinations and fluctuations in symptoms are common to both disorders.
When to see a doctor
Older people recovering in the hospital or living in a long term care facility are particularly vulnerable to delirium. Because symptoms can fluctuate and because some symptoms are "quiet" — such as depression or poor responsiveness — delirium may be missed. If you notice signs and symptoms of delirium in a person in a hospital or nursing home, report your concerns to the nursing staff or doctor rather than assuming that those problems have been observed.
Delirium occurs when the normal sending and receiving of signals in the brain becomes impaired. This impairment is most likely caused by a combination of factors that make the brain vulnerable and factors that trigger a malfunction in brain activity.
Factors that may make people more vulnerable to the development of delirium include:
Factors that are common triggers for delirium in vulnerable people include:
A number of medications can act as triggers of delirium, particularly:
Delirium may last only a few hours or as long as several weeks or months. If factors contributing to delirium are addressed, the recovery time is often shorter.
The degree of recovery depends to some extent on the health and mental status of a person before the onset of delirium. People with dementia, for example, may experience a significant overall decline in memory and thinking skills or a more rapid decline in skills. People in better health are more likely to recover fully.
People with other serious, chronic or terminal illnesses may not regain their pre-delirium levels of thinking skills or functional abilities. Delirium in seriously ill people is also more likely to lead to:
Preparing for your appointment
If you're the relative or primary caregiver of a person with delirium, you'll likely play a role in making an appointment or providing information for the doctor.
What you can do
What to expect from the doctor
Tests and diagnosis
A doctor will diagnose delirium based on the answers to questions about a person's medical history, tests to assess mental status and the identification of possible contributing factors. An examination may include the following:
Treatments and drugs
The first goal of treatment for delirium is to address any underlying causes or triggering factors — by stopping use of a particular medication, for example, or treating an infection. Treatment then focuses on creating an optimal environment for healing the body and calming the brain.
A number of simple, nondrug approaches have been found to help:
The usual drug of choice is an antipsychotic medication, which may lessen the disorganized thinking that accompanies delirium.
The most successful approach to preventing delirium is to target risk factors that might trigger an episode. Hospital environments present a special challenge — frequent room changes, use of restraints, invasive procedures, loud noises, poor lighting and lack of natural light can worsen confusion.
Strategies that have been proved to help prevent delirium in hospitalized people include:
Coping and support
A person with delirium may require a long period of recovery either in a care facility or at home. People with dementia or a terminal illness or those approaching the end of life are at particularly high risk of delirium.
If you are a relative or caregiver of a person recovering from delirium or at risk of delirium, you can take steps to improve the person's health, prevent a recurrence and help you manage your responsibilities.
Staying calm and well oriented
Preventing complicating problems
Caring for the caregiver
Organizations that may benefit you include the National Family Caregivers Association, the Alzheimer's Association and the National Institute on Aging.
Last Updated: 2010-04-24
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