Delirium: What is it, how it relates to sundowning and who it's likely to effect
"My elderly mom was admitted to a nursing home a couple weeks ago, and now seems to be hallucinating on and off, especially at night," a patient asked recently. "She has never had any mental illness. Does this means she is psychotic now?"
Although psychosis can have symptoms of delusions and hallucinations, the acute onset of this, and the fact that you note it is “on and off,” makes this seem more like delirium, so that will be the topic of this column.
The term "sundowning" refers to when these delirium symptoms occur in the late afternoon and often last into the evening.
What is delirium?
The Diagnostic and Statistical Manual of Mental Disorders Fifth Edition (DSM-5-TR) classifies delirium as a:
“Disturbance in attention (i.e., reduced ability to direct, focus, sustain and shift attention) and awareness (reduced orientation to the environment).
The disturbance develops over a short period of time (usually hours to a few days), represents an acute change from baseline attention and awareness, and tends to fluctuate in severity during the course of a day.
An additional disturbance in cognition (e.g., memory deficit, disorientation, language, visuospatial ability or perception).
The disturbances in Criteria A and C are not better explained by a preexisting, established or evolving neurocognitive disorder and do not occur in the context of a severely reduced level of arousal such as coma.
There is evidence from the history, physical examination or laboratory findings that the disturbance is a direct physiological consequence of another medical condition, substance intoxication or withdrawal (i.e. due to a drug of abuse or to a medication), or exposure to a toxin, or is due to multiple etiologies.”
Delirium can make the patient A.) agitated/hyperactive, B.) somnolent/decreased overall arousal, or C.) a mixture of each. Symptoms may include changes in consciousness, difficulty maintaining attention, disorientation, hallucinations, speech and/or swallowing issues, memory issues, emotional issues (such as fear, depression, others), and/or others.
What are common causes of delirium?
The cause of delirium is not known, but it likely has multiple etiologies. For example, an inflammatory reaction or other cellular damage of the central nervous system, disruption of circadian rhythms, imbalances of neurotransmitters and/or the endocrine system, and/or others. It typically occurs in those over age 70 (especially in those with a history of dementia), although it can occur in younger people, especially due to withdrawal from alcohol (delirium tremens) and/or other drugs, or from other causes.
There are many possible precipitating factors, such as medication side effects (for example, psychoactive and/or anticholinergic medications), infections (including urine infections, pneumonias, others), exacerbations of chronic illnesses, acute changes in medical status for whatever reason (including getting dehydrated, having low oxygen levels, others), having had certain medical interventions (such as surgery, anesthesia, others), changes in the patient’s acute living situation (including being hospitalized, especially in the intensive care unit, going to a nursing home, moving, etc.) and many others.
Who is likely to experience delirium?
Delirium is common in the elderly, specifically when they have one or more of the precipitating factors noted above; it is the most common mental disorder in older patients with a medical issue. For example, up to 20% of those over age 70 experience at least some delirium after elective surgery (it is up to 50% for high-risk surgeries), up to 30% when hospital admission is required for a medical issue, up to 75% for those who require ICU admission, and more than 75% for those in their final days.
Delirium is diagnosed based on the history and physical examination. Certain laboratory tests (for example, electrolytes, thyroid function, kidney/liver function tests, urine tests, alcohol/drug tests, others), certain brain imaging such as CT or MRI (if indicated), and other tests are usually done to identify possible triggers and to rule out other possible causes of the symptoms.
How do you treat delirium?
Treatment of delirium focuses on treating any underlying conditions identified as well as supportive care such as addressing environmental factors, addressing sleep issues, frequent interaction to reorient/reassure the patient, others. Certain patients, for example those who may have severe enough symptoms to be a danger to themselves or others, may benefit from certain medications specifically selected to treat their symptoms and to minimize side effects and symptom exacerbation.
Although delirium will often improve when the triggers/precipitating factors are addressed, it's still a marker for an overall poorer prognosis (possibly representing an overall more "frail" patient). For example, the risk of death within six months is 70% higher for patients who arrive at the emergency department with delirium (overall mortality 10% to 25%), delirium occurring in the ICU doubles the overall mortality for that admission, and overall there is a poorer prognosis for patients who develop delirium when compared to those who do not.
Jeff Hersh, Ph.D., M.D., can be reached at DrHersh@juno.com.
This article originally appeared on MetroWest Daily News: Delirium and sundowning: What it is and what causes it
