Delirium is a sudden and severe brain function change that causes a person to appear confused or disoriented or to have difficulty maintaining focus, thinking clearly, and remembering recent events. A serious medical illness (i.e., an infection) usually triggers delirium. It can also be brought on by particular medications, drug withdrawal, or intoxication. Older patients over 65 years are at the highest risk for developing delirium. While some patients become agitated, others may be quietly confused.
Delirium is prevalent in hospitals and nursing homes and can appear in private homes, especially in high-risk patients. A high-risk designation includes advanced age, with underlying brain diseases such as dementia, stroke, or Parkinson’s disease (mainly when there are current memory problems). Additional high-risk indicators:
- using numerous medications
- multiple medical problems
- sudden withdrawal of regular medication
- cessation of chronic alcohol use
- undertreated pain
- poor eyesight or hearing
- sleep deprivation.
Delirium is different from dementia because it comes on suddenly, in hours to days, rather than months to years. Unlike dementia, delirium is usually temporary and is resolved when the underlying cause is addressed.
The treatment goal is to address the cause of delirium when possible and keep the person safe.
It is unclear why or how delirium develops. The most common potential causes include infections, medications, and organ failure (such as severe lung or liver disease). The underlying illness or condition is not necessarily a brain problem.
How common is delirium? About 30 percent of older patients experience delirium during hospitalization, the incidence being higher in intensive care units. Following surgery, from 10-50 percent of older patients risk developing delirium.
Delirium is not a disease but a group of symptoms. The key features include abnormal changes in the person’s consciousness level and thinking. The changes may be subtle initially. The person often has difficulty maintaining focus and may frequently change the subject in a conversation, mention strange ideas, have difficulty retaining new information, or be disoriented (in place or in time). Some patients experience visual hallucinations.
These symptoms develop over a short period (hours to days) and tend to become intermittently worse, especially in the afternoon and evening. This sudden change helps differentiate delirium from dementia.
Delirium may be challenging to perceive because changes in behavior could be attributed to a person’s age, a history of dementia, or other mental disorders. Also, the symptoms can come and go, such that a person has no or few symptoms early in the day but progressively worsens later or in the evening.
When a caregiver or family member suspects that their relative has delirium, the person must be medically evaluated promptly to diagnose the underlying cause and start treatment. Some life-threatening conditions can induce delirium, so it is crucial to be assessed quickly. The clinician evaluating a person with suspected delirium must know the patient’s full medical history and all current medications, both prescribed and over-the-counter.
Tests include Laboratory testing — Blood, urine tests, and a chest x-ray is often required to exclude pneumonia. Brain imaging tests (CT) scan or (MRI) scan of the head may be recommended. A Lumbar puncture -where several tests are done on the fluid to determine if an infection could be causing delirium and EEG testing – which measures the brain’s electrical activity.
There is no specific treatment for delirium. Instead, treatment focuses on several fundamental principles:
- Avoiding factors that trigger or aggravate delirium, such as a medication.
- Identifying and treating the underlying illness.
- Providing supportive and restorative care.
- Controlling dangerous and disruptive behaviors to avoid harm to the patient or others.
With the first delirium episode, the initial treatment is often provided in a hospital setting. This hospital stay allows the health care provider to monitor the patient, begin treatment of the underlying problem, and develop a long-term supportive care plan with the patient and their family.
The goal of supportive care is to preserve the patient’s health, prevent complications, and avoid factors that aggravate delirium.
Delirium has an enormous impact on the health of older people. Patients with delirium can experience extended hospitalizations and a diminished ability to function independently. They are at a higher risk for requiring a long-term care facility. Delirium can be disturbing for the patient, as well as for the caregiver and family. Delirium can sometimes clear up within hours or days. In other cases, it can take weeks or months.