Featured Research

from universities, journals, and other organizations

Delirium increases the risk of developing new dementia 8-fold in older patients

Date:
August 9, 2012
Source:
University of Cambridge
Summary:
Older people who have experienced episodes of delirium are significantly more likely to develop dementia, according to new research.

Older people who have experienced episodes of delirium are significantly more likely to develop dementia, according to new research. The study is published in the journal Brain on August 9.

When in hospital, older people sometimes become acutely confused and disorientated. This condition, known as delirium, affects at least 15 per cent of older people in hospitals and has long thought to be simply a temporary side effect of other illness (such as an infection, a reaction to a medication or an operation). However, the new research shows that episodes of delirium can have long term effects -- increasing the future risk of dementia eight-fold.

Dr Daniel Davis, lead author of the paper from the University of Cambridge, said: "This means that delirium, or the acute causes of delirium, could be a newly discovered cause of dementia. This is important, because although delirium is extremely common, less than a quarter of cases are actually diagnosed in hospitals."

Scientists at the University of Cambridge and the University of Eastern Finland recruited 553 people aged 85 and over, and assessed their memory and thinking over 10 years. Of the patients who had previously experienced at least one episode of delirium prior to the study, 77 per cent also had dementia. In comparison, only 33 per cent of the patients who had no previous history of delirium had dementia. They also recorded the number of episodes of delirium throughout the study.

In people without pre-existing dementia, experiencing delirium resulted in an eight-fold increase in the risk of dementia. In individuals with existing dementia, delirium was associated with an acceleration of dementia severity, loss of independence in physical functioning, and higher mortality.

Dr Davis added: "Worsening confusion and disorientation in older persons does not attract much attention among clinical staff and many believe that delirium is simply an inconvenient consequence of illness. However, this research suggests the possibility that delirium, or the problems giving rise to delirium, may be actually causing brain damage.

"Because some delirium is preventable, it is plausible that delirium prevention may lead to dementia prevention. We now urgently need to test if better delirium care can prevent dementia, or prevent further decline in patients who already have dementia."

The Wellcome Trust-funded study also found, for the first time, that there may be differences in the brains of people who have had delirium compared to those without delirium. Dementia is known to result from a several different pathological processes (e.g. accumulation of abnormal proteins, or blockages in blood vessels). However, this study found that when individuals had both delirium and dementia, these standard neuropathological markers were not enough to explain the dementia. This raises the important possibility that dementia occurring after delirium had alternative pathological processes causing the dementia.

Professor Clive Ballard, Director of Research at Alzheimer's Society, said: "Scientists have believed there could be a link between delirium and dementia for many years. This robust study adds weight to this knowledge. With hospitalisation thought to be a cause of delirium, it's vital that healthcare professionals recognise the potential long term impact of delirium and are aware that older people who experience episodes could be susceptible to developing dementia."

Dr Karin Neufeld, President-Elect of the American Delirium Society and Director of General Hospital Psychiatry at Johns Hopkins Hospital, commented: "Research on delirium has repeatedly highlighted the association between cognitive impairment, and dementia and the development of delirium in the hospital setting in elderly individuals.

"This important research suggests that preventing delirium might be an important way to decrease the onset and progression of dementia in some people. The implication is that we, as healthcare professionals, need to redouble our efforts to detect and prevent delirium in hospitalised patients."


Story Source:

The above story is based on materials provided by University of Cambridge. The original story is licensed under a Creative Commons license. Note: Materials may be edited for content and length.


Journal Reference:

  1. Daniel H. J. Davis, Graciela Muniz Terrera, Hannah Keage, Terhi Rahkonen, Minna Oinas, Fiona E. Matthews, Colm Cunningham, Tuomo Polvikoski, Raimo Sulkava, Alasdair M. J. MacLullich, and Carol Brayne. Delirium is a strong risk factor for dementia in the oldest-old: a population-based cohort study. Brain, 2012 DOI: 10.1093/brain/aws190

Cite This Page:

University of Cambridge. "Delirium increases the risk of developing new dementia 8-fold in older patients." ScienceDaily. ScienceDaily, 9 August 2012. <www.sciencedaily.com/releases/2012/08/120809090704.htm>.
University of Cambridge. (2012, August 9). Delirium increases the risk of developing new dementia 8-fold in older patients. ScienceDaily. Retrieved August 23, 2014 from www.sciencedaily.com/releases/2012/08/120809090704.htm
University of Cambridge. "Delirium increases the risk of developing new dementia 8-fold in older patients." ScienceDaily. www.sciencedaily.com/releases/2012/08/120809090704.htm (accessed August 23, 2014).

Share This




More Mind & Brain News

Saturday, August 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Lost Brain Cells To Blame For Sleep Problems Among Seniors

Lost Brain Cells To Blame For Sleep Problems Among Seniors

Newsy (Aug. 21, 2014) According to a new study, elderly people might have trouble sleeping because of the loss of a certain group of neurons in the brain. Video provided by Newsy
Powered by NewsLook.com
Do More Wedding Guests Make A Happier Marriage?

Do More Wedding Guests Make A Happier Marriage?

Newsy (Aug. 20, 2014) A new study found couples who had at least 150 guests at their weddings were more likely to report being happy in their marriages. Video provided by Newsy
Powered by NewsLook.com
Charter Schools Alter Post-Katrina Landscape

Charter Schools Alter Post-Katrina Landscape

AP (Aug. 20, 2014) Nine years after Hurricane Katrina, charter schools are the new reality of public education in New Orleans. The state of Louisiana took over most of the city's public schools after the killer storm in 2005. (Aug. 20) Video provided by AP
Powered by NewsLook.com
Researcher Testing on-Field Concussion Scanners

Researcher Testing on-Field Concussion Scanners

AP (Aug. 19, 2014) Four Texas high school football programs are trying out an experimental system designed to diagnose concussions on the field. The technology is in response to growing concern over head trauma in America's most watched sport. (Aug. 19) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins