December 2022

There’s no test that shows if you have delirium. Or they can be serious and even life-threatening, especially for people who are already sick. Delirium happens when your body or brain is under too much stress. Symptoms can vary from person to person. Delirium is new or worsened confusion and changes to your mental abilities. Cleveland Clinic is a non-profit academic medical center.

• Yet, it is not clear whether the DMN is the primary network that is dysregulated in delirium, or if it is one of the various networks that become dysfunctional.
• The symptoms tend to fluctuate, meaning they are more severe at some times, and less severe at others.
• Signs of delirium may sometimes be confused with symptoms of dementia, depression, or fatigue.
• (A, B) Representative examples of lateral ventricle size in two intensive care unit (ICU) survivors with no preexisting cognitive impairment (by patient and surrogate reports and review of records).

How is delirium diagnosed?

Delirium is common in hospitalized or seriously ill older adults but can also result from infections, surgery, medications, or substance withdrawal. For instance, the English medical writer Philip Barrow noted in 1583 that if delirium (or “frensy”) resolves, it may be followed by a loss of memory and reasoning power. About 5–10% of older adults who are admitted to hospital develop a new episode of delirium while in hospital. The most recent area of the hospital in which delirium is just beginning to be monitored routinely in many centers is the Emergency Department, where the prevalence of delirium among older adults is about 10%. The causes of delirium depend on the underlying illnesses, new problems like sepsis and low oxygen levels, and the sedative and pain medicines that are nearly universally given to all people in the ICU p. The implications of such an “acquired dementia-like illness” can profoundly debilitate a person’s livelihood level, often dismantling his/her life in practical ways like impairing one’s ability to find a car in a parking lot, complete shopping lists, or perform job-related tasks done previously for years.

Clinical Trials

• People who may have delirium are given a mental status test.
• When people stop using such substances, they may have withdrawal symptoms, including delirium.
• We thus conclude the article with a discussion of challenges for delirium pathophysiology research, including heterogeneity of sample populations, precipitating etiologies and methodological approaches, and an exposition of ways that neuroimaging, neurophysiology, and animal models can be leveraged in future research of delirium.
• Yet the sum of the current evidence suggests that there are a few, distinct but overlapping “pathways to delirium” that lead to system-wide failure of multiple cerebral networks, and likely explain the majority of delirium cases.

The use of S100B as a potential biomarker for delirium has the benefit that it represents a direct measure of central, brain changes that are detectable in serum. CRP is induced by IL-6 action on the gene that transcribes CRP during the acute phase of an inflammatory response.45 The relationship of CRP to delirium has been explored in many studies, measured both pre- and postoperatively. In addition, EEG can be recorded at the bedside in acutely ill or postsurgical patients, making it a more pragmatic modality in the study of delirium compared to MRI, fMRI, or PET. Additional insights into delirium pathophysiology may be gleaned from studies of electroencephalography (EEG). Multivariable analysis identified lower preoperative regional cerebral oxygen saturation (rScO2), averaged across hemispheres and corrected for hypoxemia, as a risk factor for POD, independent of age, cognitive status, and operative risk.15 (C) Correlation between posterior cingulate cortex regional cerebral metabolic rate and WAIS-IV digit span score, a measure of attention, during delirium.

Although complex cognitive testing may be precluded by the experimental method of inducing critical illness and delirium including sickness behaviors, pain, analgesics and motivational changes are some of many approaches that have been able to assess some aspects of delirium-related changes. Functional markers include behavior (cognitive deficits, activity, anxiety- and depressive-like behavior), imaging modalities (fMRI, MRI, PET, NIRS), and EEG patterns (increase in delta and theta activity, decrease in alpha and beta, increase in episodic bursts of spikes). Environmental factors to induce a delirium-like state in animal models include sleep deprivation through light, sound, and physical disturbance. The screening and diagnosis of delirium, even in intubated patients, are based on bedside examination and primarily depend on language-based tools such as the Diagnostic and Statistical Manual, version V (DSM-5),64 Confusion Assessment Method (CAM), and CAM-ICU.65-67 Thus, many animal models have focused on recreating the clinical states that typically cause delirium. Despite mounting literature suggesting a direct relationship between these biomarkers and delirium, the fact that these biomarkers are not specific to delirium limits their prognostic utility in routine clinical care.

Alcohol withdrawal delirium

To reduce the chance of delirium coming back, follow your treatment plan carefully to address underlying causes. Counseling is also used as a treatment for people whose delirium was brought on by substance use. In some cases, your doctor may recommend that you stop taking certain medications if they are causing delirium. If a bacterial infection is causing the delirium symptoms, antibiotics may be prescribed.

Up to 39% of the time, delirium is caused by medications. Around one-third of hospital patients over age 70 experience delirium at some Delirium Tremens Symptoms point during their hospital stay. People with mixed delirium have hyperactive delirium symptoms at some times, and hypoactive delirium symptoms at other times. When you or your loved one is discharged from the hospital, talk to your healthcare provider about follow-up care and develop a plan to avoid delirium at home. If you notice any signs of delirium in yourself or a loved one, seek immediate medical care. Antipsychotic medication needs to be used cautiously when treating delirium, especially for people with dementia, because of possible side effects.

This is a distressing personal and public health problem and continues to receive increasing attention in ongoing investigations. Between 50% and 70% of people admitted to the ICU have permanent problems with brain dysfunction similar to those experienced by people with Alzheimer’s or those with a traumatic brain injury, leaving many ICU survivors permanently disabled. Institutionalization was also twice as likely after an admission with delirium (meta-analysis of seven studies). In the only prospective study conducted in the general population, older persons reporting delirium also showed higher mortality (60% increase). The antidepressant trazodone is occasionally used in the treatment of delirium, but it carries a risk of over-sedation, and its use has not been well studied.

Risk factors for delirium

Your doctor may prescribe medications to treat the underlying cause of your delirium. A healthcare professional can diagnose you with delirium. Any condition or factor that significantly changes your brain function can cause severe mental confusion. It’s possible for younger people to experience delirium too, although it’s less common.

Predisposing factors

The consistent demonstration of these perturbations among delirious patients suggests they may fall along the causal pathway. Some phenomena, such as elevation in IL-6, CRP, and other markers of systemic inflammation, are no doubt a result of the precipitating factor leading to delirium (e.g., from sepsis). 3 features an overview of current approaches to induce a delirium-like state in animal models, and ways to measure the outcomes of this state.

What tests diagnose delirium?

Symptoms of delirium are sometimes confused with symptoms of dementia. Predisposing conditions include global atrophy, white matter hyperintensities, and, among perioperative patients, elevated markers of systemic inflammation, suggesting the absence of these features may confer some resilience to the precipitants of delirium. Lastly, the potential use of novel diagnostic and translational methods, such as advanced EEG signal processing and neuroimaging, may contribute to our knowledge of mechanisms of delirium and the likelihood of long-term negative outcomes if they can be incorporated into clinical and preclinical studies. In addition, it is important to understand instances when the use of specific medications may significantly potentiate or otherwise modify changes to neuroinflammatory pathways, sleep–wake cycle disturbances, and neurotransmitter disruption and thus worsen rather than mitigate delirium. Thus, the growing inclusion of EEG and other home-cage or more naturalistic behaviors (e.g., sleep) have high translational value in addition to the use of cognitive approaches that take account of potential decreased activity or motivation. These challenges highlight the importance of clinically guided basic science research, as many of these factors can be addressed with animal models, including the potential to directly measure changes in brain tissue.

Protocol differences in the number and timings of research measurements relative to the medical challenge and the delirium, length of follow-up, and the required medical interventions used are all intrinsic to optimal treatment of patients, but increase the likelihood of variability in experimental data. Different population characteristics include age, sex, and racial and genetic diversity, and critically important is the medical cause of the delirium whether elective surgery, injury, or critical illness. Other phenomena, such as the presence of widespread areas of invariant delta activity in the EEG, have been replicated in delirium among multiple populations and across etiological risk factors. These symptoms were appreciated by the increased levels of inflammatory mediators such as IL-1, tumor necrosis factor (TNF)-α, type I interferons, and COX-2 within the brain.81-84 Within these models, peripheral challenges were noted, including elevated levels of TNF-α and IL-1. EEG measurements revealed profoundly disordered circadian rhythms representative of disruption experienced by patients in the ICU with delirium.76 Sleep plays a major role in the prevention or severity of delirium-like symptoms as well as being an important affected outcome of delirium.

The use of restraints has been recognized as a risk factor for injury and aggravating symptoms, especially in older hospitalized people with delirium. Because of the confusion caused by similar signs and symptoms of delirium with other neuropsychiatric disorders like schizophrenia and psychosis, treating delirium can be difficult, and might even cause death of the patient due to being treated with the wrong medications. There is evidence that the risk of delirium in hospitalized people can be reduced by non-pharmacological care bundles (see Delirium § Prevention). Older people who are in the hospital or are living in a long-term care center are at risk of delirium. The high face validity of such outcomes may even mask fundamental differences in rodent and human brain function (e.g., EEG and sleep).88-90 Nevertheless, when taken as analogs and not direct clinical mirrors of the human state, preclinical research has considerable power to elucidate underlying mechanisms and contribute to drug discovery studies. In two separate studies it has potential utility in identifying patients at risk for delirium.61,62 These and other potentially relevant biomarkers are represented in ►Table 1.

If you get help quickly, your symptoms may get better. But some cases of delirium aren’t permanent. Your loved one may say you seem like a completely different person. Your healthcare provider can give you the clearest picture based on your specific situation.

What Is Confusion?

Delirium may affect 15 to 50% of people sometime during hospitalization and is also common among residents of nursing homes. Because delirium is a temporary condition, determining how many people have it is difficult. People who have delirium need immediate medical attention.

What Is Delirium?

The recovery may take some time – weeks or sometimes even months. You can also have both at the same time. There are many different problems that can cause delirium.