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How is delirium different from dementia?


Delirium refers to a severe state of confusion in which the patient cannot think clearly, has difficulty understanding or paying attention and could suffers from hallucinations that are very real to them.

Delirium is a dysfunction of the brain that can be caused by a variety of things, such as:

  • Low oxygen to the brain or the brain’s inability to use oxygen
  • Chemical changes in the brain
  • Medications
  • Infections and severe pain

Multiple medical conditions including stroke, shock, heart, liver or kidney failure, and sepsis can also cause delirium. Those more likely to experience delirium include individuals with dementia, advanced age, surgery (particularly hip, heart or emergency), heart failure, infection or sepsis, are hard of hearing or vision and have a history of depression or on certain high-risk medications.

Delirium is not the same as dementia. Delirium comes on quickly and is not permanent, while dementia comes on over several months to years and is typically permanent.

Why does it matter?

Two-thirds of patients in the Intensive Care Unit will have delirium at some point. Between 60-80 percent of patients on a breathing machine have delirium and of these, around 70 percent are never recognized or treated.

Delirium is associated with increased time in the hospital and on the breathing machine, long-term issues with thinking, increased costs of healthcare, the need for chronic care treatment, decreased functional status and odds of dying.

Even one year after the illness that created the delirium, patients still have problems. Many survivors are unable to return to work and have increased doctor visits or need to go back into the hospital.

Additionally, some survivors experience anxiety, depression, post-traumatic stress disorder, problems similar to mild Alzheimer’s disease and even disability that affect their ability to complete activities of daily living which are routine things done every day such as putting on clothes, balancing checkbooks and cooking. 

How do you treat it?

Doctors will look for the underlying cause of the delirium and try to minimize it without medications if possible. They will do things such as stop certain types of medications, diagnose new infection or other problems, try to get the patient moving, provide hearing aids or glasses and try to get the patient to sleep better at night to be awake during the day.

Tips for family and friends:

  • Talk about family, friends, date and time using simple words and phrases
  • Provide hearing aids and glasses if the patient wears them
  • Decorate the room with pictures of loved ones
  • Play favorite music or television shows
  • Sit and comfort the patient if they are battling delirium
About Justin Sandall DO

Justin Sandall, DO, is an anesthesiologist with Anesthesia Consulting Services and an intensivist at the Neurocritical Care Unit at Ascension Via Christi St. Francis.