According to research, Alzheimer’s disease patients who have an episode of delirium are significantly more likely to experience rapid cognitive decline and memory loss than Alzheimer’s patients who didn’t experience delirium.
Delirium often develops in elderly patients during hospitalization or serious illness, and this acute state of confusion and agitation has long been suspected of having ties to Alzheimer’s and other dementias.
Alzheimer’s is an irreversible, progress form of dementia that gradually destroys a person’s ability to carry out even the simplest of tasks, and affects as many as 4.5 million individuals in the U.S. according to figures from the National Institute on Aging. There is currently no cure for Alzheimer’s disease.
The illustration depicts the pathology of Alzheimer’s – severe cortical atrophy and the triad of senile plaques; neurofibrillary tangles; and neuropil threads.
“Delirium is a potentially preventable condition,” said study author Tamara G. Fong. “Hopefully future studies can determine whether preventing delirium may improve or delay memory problems in Alzheimer’s patients.”
For the study researchers tested the memory, thinking, and concentration skills of 408 Alzheimer’s patients at the beginning of the study and every six months for at least a year and a half. During that time, 72 of the study participants developed delirium.
The study found that the rate of cognitive decline was three times faster in Alzheimer’s patients who had an episode of delirium compared to those who did not. “Our study suggests that over 12 months, Alzheimer’s patients who become delirious experience the equivalent of a 18-month decline in thinking and memory skills compared to those who do not experience delirium,” said Fong.
Among Alzheimer’s patients who developed delirium, the average decline on cognitive tests was 2.5 points per year at the beginning of the study, but after an episode of delirium there was further decline to an average of 4.9 points per year.
It’s estimated that delirium occurs in up to 89 percent of Alzheimer’s patients during hospitalization. Fong says that delirium in elderly patients should be avoided for many other reasons. “For example, delirium greatly increases the risk of serious complications in hospitalized patients,” she said. “Alzheimer’s patients need to be monitored more closely for delirium, and prevention strategies could be used such as avoiding medications that have delirium as a potential side effect and treating patients as outpatients where possible to avoid hospitalization.”
References:
1. Tamara G. Fong, et al. American Academy of Neurology.
2. Image by Wellcome-images.
