Overview

Delirium is a state of mental disorientation and confusion. Individuals with this symptom may act confused and unsure of where they are or appear extremely sleepy and lethargic. Symptoms develop quickly, often within a matter of hours or days. Along with disorientation and tiredness, common delirium symptoms include hallucinations,1 irritability, impaired memory, and delusions.2  

Certain groups are at a higher risk of developing delirium, including adults over 70 and individuals in the hospital, especially those in the intensive care unit (ICU). While delirium has been linked to worse outcomes for these groups, it is preventable and treatable. Healthcare providers may try to remedy the situation or environment causing the delirium before treating direct symptoms. 

If someone you know develops delirium, the experience may be unnerving. Maintaining a soothing presence and reassuring them of the situation may help both of you remain calm. For individuals in a nursing home or the hospital, healthcare providers can provide guidance on reorienting the person. They may also prescribe antipsychotic drugs to manage aggression or agitation associated with delirium.

Symptoms

Symptoms of delirium may depend on the type a person is experiencing. There are three types, including hypoactive, hyperactive, and mixed delirium, as follows. 

Hypoactive delirium

The hypoactive type of delirium is the most common but least recognized presentation of delirium. It is often confused with sleepiness, as individuals may appear subdued, disoriented, tired, or depressed. In this state, the individual may be confused, unable to talk properly, and unsure about their surroundings. Hypoactive delirium is the most common form of delirium in older adults. 

Hyperactive delirium

Hyperactive delirium presents as restlessness and agitation. The individual may experience hallucinations or delusions. Disorientation may cause them to be aggressive or combative. Hyperactive delirium can sometimes be confused with schizophrenia3 or dementia. 

Mixed delirium

People with mixed delirium fluctuate between symptoms of hypoactive and hyperactive delirium. They may be sleepy in the morning and pacing or “on edge” by the afternoon. 

Symptoms of delirium often develop quickly in a matter of hours. Some symptoms may present in any type of delirium a person develops, including the following: 

  • Attention impairment: The individual may struggle to remember questions or instructions directed toward them, asking them to be repeated several times. They may also be easily distracted and have trouble focusing on topics.
  • Neurological symptoms: The individual may display an unsteady gait, difficulty reading and writing, involuntary movements, tremors, and difficulty finding the word they want to use. 
  • Sleep disturbances: Someone with delirium may have unorthodox sleep patterns, staying awake for hours during the night and falling asleep during the day. 
  • Memory problems: Short-term memory is often impacted by delirium. The person may not remember where they are, why they are there, or the current date.
  • Behavioral and emotional changes: Appearing as extreme mood swings, the individual may fluctuate from one emotion to another, including anger, irritability, excitement, and depression. Sluggishness and slow movements or making moaning sounds are behavioral changes associated with delirium.

Early diagnosis of delirium can help increase the likelihood of positive short- and long-term treatment outcomes. Along with a discussion of an individual’s symptoms and medical history, a healthcare professional will typically conduct neurological and physical exams prior to providing a diagnosis. These assessments are often accompanied by a mental status exam, which is used to evaluate cognitive function, mood, and behavior. 

Causes

Increased age is one of the most common causes of delirium. People over 80 have a higher chance of developing the condition. In a nursing home, up to 60% of residents over the age of 75 may be experiencing delirium at any given time. A person who has dementia is also at a higher risk of experiencing delirium, and it can sometimes be difficult to discern if an older adult has dementia or temporary delirium. 

Hospitalization is also commonly connected to delirium, with the above study finding that 10% to 30% of medically ill hospitalized patients develop delirium during their stay. The severity of a person’s condition increases their chance of developing delirium. In addition, risk factors like organ failure, being in the ICU, and undergoing complex surgery with anesthesia make delirium more likely. 25% of patients with cancer may experience delirium, as well as 30% to 40% of hospital patients with HIV infection. Other hospital-related causes of delirium include sepsis, dehydration, oxygen deprivation, and low blood sugar. Strokes are also associated with an increased risk of delirium

Up to 39% of delirium cases may be caused by medication side effects, especially if a person is taking psychoactive medications or anticholinergic drugs. An individual may experience delirium when stopping a medicine as they go through withdrawal. Additionally, symptoms of delirium can occur during severe alcohol withdrawal.4  

Additional causes of delirium may include: 

  • Sleep deprivation
  • Malnutrition
  • Difficulty seeing or hearing
  • Parkinson’s disease
  • Dialysis
  • Terminal illness

Treatments

To treat delirium, medical professionals can first identify and correct the medical condition causing the delirium. Medication and other treatment options may also be utilized to correct delirium and prevent it from recurring. 

Therapy 

While delirium is often treated by correcting the condition causing it, therapy may be beneficial in some cases. For example, some individuals who experience delirium later show symptoms of post-traumatic stress disorder (PTSD).5 Therapy, such as cognitive-behavioral therapy, may improve symptoms of PTSD and help an individual move past the traumatic event. 

Because delirium is often associated with advanced age, it may be helpful for family members and caregivers of older people to participate in therapy, especially in instances of prolonged delirium. Doing so may prevent caregiver burnout and equip family members to process the changes in their loved ones appropriately. 

Medication

It’s important to note that the first step in managing delirium is to identify and correct any underlying conditions that may be causing it. Treating a medical condition may involve stabilizing fluid and electrolyte imbalances, addressing infections, regulating glucose levels, and managing any organ system dysfunction. 

Currently, there are no medications approved by the US Food and Drug Administration (FDA) specifically for delirium management. Therefore, any use for this purpose is considered off-label. The use of antipsychotic medications for delirium is based on limited evidence. They may be used to treat severe agitation and reduce the duration of delirium. Current studies have shown that haloperidol, risperidone, and olanzapine may help to manage the symptoms associated with delirium. If a patient responds to a medication regimen, it can be helpful for doctors to monitor their improvement and slowly taper the antipsychotics over time to prevent symptoms from rebounding. However, antipsychotic medications should be prescribed for short-term management only, as they have been associated with negative side effects, including an increased risk of mortality and potential stroke in dementia patients.

Consult a medical doctor before starting, changing, or stopping a medication for any condition. This information is not intended to provide medical, professional, or licensed advice and is not a substitute for consultation with a healthcare professional. 

The BetterHelp platform is not intended for any information regarding which drugs, medication, or medical treatment may be appropriate for you. The content is providing generalized information, not specific for one individual. You should not take any action without consulting with a qualified medical professional.

Other treatment options

Because delirium can be so confusing, the presence of a loved one is often helpful in supporting an individual in reorienting themselves. This support provides comfort, and the friend or family member can remind the individual of the date, time of day, and reason they are in the hospital. 

It may be helpful to find ways to avoid under-stimulation and overstimulation. Cues about an individual’s current situation can be reassuring, such as allowing light to enter during the day and having a hospital sign in the room. However, overstimulation, such as frequent vital checks at night, can be avoided as much as possible. 

Self-care

Studies have revealed that sleep deprivation and delirium are connected. One way to prevent the onset of delirium is to ensure you get enough sleep at night. For patients undergoing long-term care in a hospital, this tip may mean advocating for minimal interruptions during the night. During a study at The Johns Hopkins Hospital, researchers improved the odds of a patient avoiding delirium by 54% by:

  • Creating a calm nighttime environment with low lighting and minimal pages
  • Consolidating staff visits during the night
  • Offering ear plugs, sleep masks, and tranquil music
  • Discouraging sleep medicines that are often linked to delirium

Avoiding substance use may also prevent delirium, as both intoxication and withdrawal can lead to the condition.

Resources

Knowing where to turn when you or someone you love experiences delirium can make the condition seem less alarming and help you be better equipped if it does occur. Below are a few resources to turn to. 

Therapy

If you or someone you know has developed delirium, you may be affected by the stress of the condition. If you have an older parent or grandparent with dementia who experiences delirium, it may be challenging to know the appropriate way to respond to delusions or hallucinations. Mental health care can help both older adults and their caregivers prepare to address the emotional and cognitive challenges of delirium.

One way to be better equipped is to participate in talk therapy. By working with a licensed mental health provider, you may better understand the condition and respond appropriately. A quick way to find therapy is through online therapy platforms like BetterHelp, where you can be matched with a therapist and begin treatment, often within 48 hours of signing up. 

Alzheimer's organizations

Since delirium is often associated with advanced age or mistaken for dementia, several Alzheimer’s organizations offer helpful resources, including the following: 

Additional resources where you can learn more about delirium include the following.

For help with substance use, contact SAMHSA’s National Helpline at 1-800-662-HELP (4357).

Research

Delirium can sometimes be mistaken for dementia due to similar symptoms. Researchers in the United Kingdom recently completed a study to determine the link between the two conditions. They followed 12,949 patients who experienced an episode of delirium for an average of 741 days. They estimated that within five years, 31% of the patients had developed dementia, confirming that the conditions are connected. The researchers also emphasized that this statistic reinforces the importance of recognizing and treating delirium as quickly as possible. 

While more than 30 tools are currently available to identify delirium, almost none can determine the severity of the condition. However, this information can be critical to optimal care for delirium patients. Researchers from Harvard Medical School, Hebrew SeniorLife, and Beth Israel Deaconess Medical Center created an assessment to measure the severity of a patient’s delirium. After testing it, they found that the tool was able to provide measurements of severity that were significantly associated with patient outcomes.  

Ideally, scientists want to eliminate as many cases of delirium as possible. Researchers have been able to confirm a few strategies effective in preventing delirium. Two strategies are the Hospital Elder Life Program, which has been able to decrease cases of delirium by 40%, and the ABCDEF Bundle, which has been proven to decrease delirium cases and increase patient survival rates. These strategies include interventions such as:

  • Allowing for uninterrupted sleep
  • Avoiding medication that increases the risk of delirium
  • Having someone present when a patient wakes up to help them become oriented
  • Ensuring that a patient has access to glasses or hearing aids

Statistics

A new tool can identify delirium in 94% to 100% of cases

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Previously, only 60% of cases of delirium were easily identifiable by medical professionals. However, 2022 research shows that a new tool called the Confusion Assessment Method can identify this symptom with 94% to 100% accuracy. 1

Below are more statistics on delirium:

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