Delirium is a brain-related condition where there is a change in a person’s thinking, and behaviour can come and go. The person often has difficulty paying attention, may be very sleepy or restless, or be thinking in a disorganised way.
Dementia Daily spoke with Associate Professor Gideon Caplan, Director of Geriatric Medicine at the Prince of Wales Hospital, who recently led a ground-breaking study looking at how and why delirium occurs.
“Understanding what’s happening in the brain in delirium is vital because we have no licensed treatment for delirium to use in our Emergency Departments or on our wards. To discover treatments, we need to know what we’re treating,” Associate Professor Caplan said.
“One in four people over 65 experience delirium and it is even more common in people with dementia when they go into hospital,” he added.
Wanting to find out why, Associate Professor Caplan and his team have led research, published in the Journal of Cerebral Blood Flow & Metabolism, comparing the brain scans of people who were displaying delirium, before and after the episode.
Thirteen elderly participants were scanned during delirium and six were scanned again after resolution. On analysis of the brain scans, cortical hypometabolism was evident in all participants during delirium and improved with delirium resolution.
In other words, the study has confirmed that through abnormal glucose metabolism, the parts of the brain connected with attention, executive function and cognitive function (such as memory), are impaired in delirium, as they are not metabolising glucose correctly.
Of interest, the findings of the study also showed the extent of the reversible decrease in glucose metabolism seen with delirium is equal in magnitude to the average decrease in glucose metabolism seen in a year in a person with Alzheimer’s dementia.
So, what next? Associate Professor Caplan hopes to discover a treatment for delirium.
“We now have Ethics approval and need one more approval before we start our first intervention trial. We are also continuing to expand the PET [brain] scan study to understand whether there are differences between different types of delirium,” he said.
You can read the original research here
For more information on delirium, read the Alzheimer’s Australia Helpsheet here