Recent studies show that patients with Alzheimer’s Disease (AD) who are hospitalized are at increased risk for further cognitive decline, institutionalization, and death in the year following their hospital stay. These risks are highest among those who develop delirium while being hospitalized. Little attention has been paid to the consequences of delirium on cognitive deterioration among patients with AD. Most studies have focused on short-term cognitive outcomes, but few have addressed whether these changes result in enduring problems in cognitive function.

Examining Long-Term Changes Following Delirium

In the August 20, 2012 online issue of the Archives of Internal Medicine, a study by senior investigator Sharon K. Inouye, MD, MPH, myself, and other colleagues explored the long-term trajectory of cognitive decline among older adults with AD who experienced delirium while they were hospitalized. The rate of cognitive deterioration was monitored for up to 5 years before and 5 years after hospitalization. Delirium in patients with AD was independently associated with cognitive deterioration for up to 5 years after hospitalization; the rate was roughly twice that of patients with AD who did not develop delirium while hospitalized.

Delirium is a Medical Emergency

In our analysis, delirium developed in 56% of the study group. Unfortunately, research suggests that delirium is recognized by physicians in fewer than 30% of hospital patients. Our study serves as an alarm to the long-term dangers of delirium on the development and progression of long-term cognitive impairment. Physicians should handle delirium cases among AD patients as they would a true medical emergency.

Strategies to Prevent Delirium

Efforts are needed to incorporate delirium prevention routinely into standard practices for dementia patients. This will help ensure that timely interventions, including non-pharmacologic protocols, are initiated. Routine screening for delirium is an important first step. Brief cognitive screening tests are widel

y available and can help improve delirium screening at the bedside. For high-risk patients, greater attention should be paid to reorientation, therapeutic activities, mobility, hydration, and other elements from the Hospital Elder Life Program ( to prevent delirium. We shouldn’t wait for delirium to happen or just accept that this is an inevitable complication. Instead, we need to work to implement proven interventions that prevent delirium.

Study after study has demonstrated the effects of delirium on long-term cognitive impairment in various patient populations, includ

ing those in the ICU and those undergoing surgery. As Americans continue to live longer, it’s imperative that we seek out more ways to prevent and treat delirium. Greater focus is needed on addressing the management of comorbi

d disease, ceasing use of potentially offending medications, and modifying environmental factors. It’s also important to find ways to rehabilitate the brain after acute illnesses so that we can mitigate the long-term cognitive decline associated with delirium.


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