Confused, Sick and Hospitalized

Delirium during hospital stays for critical illness led to long term cognitive impairment

/ Author:  / Reviewed by: Joseph V. Madia, MD Beth Bolt, RPh

(RxWiki News) Making it through a hospital stay with a serious illness and a visit to the intensive care unit can take a toll on someone. While the body can heal, researchers are urging patients and caregivers to be aware of some mental health issues that can present after discharge.

A recent study looked at ICU patients who had experienced life-threatening health problems to see if they experienced in-hospital delirium. The researchers also followed up with the patients to see if they had long-term cognitive impairment for the following year.

They found that most participants experienced in-hospital delirium lasting about four days. Additionally, a significant number of those patients had cognitive dysfunction that continued for months and sometimes a year after they returned home.

The researchers noted the importance of learning more about in-hospital delirium and its consequences for survivors of critical illnesses.

"Know who will be advocating for you if you are seriously ill."

Pratik Pandharipande, MD, MSci, led the study in order to learn more about cognitive impairment that sometimes occurs with survivors of critical illnesses.

Survivors of critical illness or health issues that require intensive care frequently report experiencing delirium during and after their hospital stay. Delirium is characterized by severe confusion. Not much is known about this type of cognitive dysfunction.

To learn more about the delirium that critically ill patients experience, the study enrolled 821 people who were in the Intensive Care Units (ICU) of two hospitals and who had experienced respiratory failure or shock. The median age of the patients was 61 years old, and only 6 percent of the participants had experienced delirium before their hospital stay.

They evaluated the patients for delirium while they were in the hospital, then they evaluated their cognitive functioning 3 months and 12 months after they had been discharged. They specifically looked for how long the delirium lasted and whether sedatives or painkillers were given to the patients.

Of the 821 patients, 74 percent experienced delirium during their hospital stay, with a median length of four days.

Three months after being released from the hospital, 40 percent of the participants had cognition scores that were consistent with moderate traumatic brain injury, and 26 percent had scores similar to mild Alzheimer's patients.

In the 12 months after patients had been discharged, the patients' average scores had improved only slightly. Thirty-four percent had cognition scores on par with moderate traumatic brain injury, and 24 percent had scores consistent with mild Alzheimer's disease.

Additionally, patients who had a longer episode of in-hospital delirium had significantly lower cognition scores at three and 12 months after being discharged from the hospital.

The cognitive impairment affected both young and old patients. It seemed most strongly tied to the length of in-hospital delirium, regardless of the patient's exposure to sedatives or painkillers.

The researchers concluded that critical illness was strongly linked to delirium, and many patients who experienced bouts of in-hospital delirium had long-term cognitive impairment. However, they also noted that the study had limitations because they were unable to evaluate the participants' cognitive functioning prior to their critical illness.

Although the researchers did not analyze the cause of the delirium, they noted that it has been associated with inflammation and could cause the brain to waste away.

The authors of the study called for more research to be conducted on in-hospital delirium and cognitive impairment, as there are no known prevention or treatment strategies.

The article was published in the New England Journal of Medicine on October 3.

The research was supported by grants from the National Institute of Health, the Veterans Affairs Clinical Science Research and Development Service, and others. Some of the authors reported conflicts of interest outside the scope of the article.

Review Date: 
October 3, 2013
Last Updated:
October 3, 2013