Delirium Episodes Could Hasten Alzheimer's-Linked Decline

May 7 -- WEDNESDAY, May 6 (HealthDay News) -- The delirium sometimes experienced by people with Alzheimer's who are hospitalized might accelerate their cognitive decline, a new study shows.

Researchers found that people with Alzheimer's who had an episode of delirium while in the hospital had a rate of cognitive decline that was three times faster than that of those who didn't experience delirium.

"From a clinical standpoint, this study suggests that over 12 months, patients with AD [Alzheimer's disease] who become delirious experience the equivalent of an 18-month decline compared to those who do not experience delirium," the study's authors wrote.

What might an 18-month decline in cognitive ability signify for the average person with Alzheimer's? That can vary depending upon the individual, according to Dr. Tamara D. Fong, an instructor of neurology at Harvard Medical School and the study's lead author.

For example, someone who is mildly forgetful about the details of a conversation might not, 18 months later, be able to drive, balance a check book or recognize relatives not frequently seen, Fong said.

But there was good news in the findings as well.

"Delirium is preventable, so we can actually design an intervention for a disease for which we have no cure at the present time," she said. Prevention strategies would probably involve multiple components, Fong said, including such things as making sure people with Alzheimer's who are hospitalized have their glasses and hearing aides on so that they remain as oriented as possible and keeping them out of the hospital by foregoing elective surgeries.

Further training about delirium for hospital staff also might help. "Delirium is sometimes hard to diagnose and probably is under-recognized, even in a hospital setting," she said.

The study, published in the May 5 issue of Neurology, compared the speed of cognitive decline among 408 people with Alzheimer's, 72 of whom developed delirium during the course of their illness.