I thought it might be a good idea to review dementia and delirium (it helps that it's something I'll be addressing in class soon).
If you don't remember what dementia is (no pun intended), it is a syndrome that includes many cognitive deficits that include memory problems. Most people are familiar with Alzheimer's type dementia, but dementia can also be caused by vascular problems, Parkinson's disease, substance abuse, as well as other causes.
While the different types of dementia do look a little different from each other, in general there is a gradual decline in memory and thinking ability.
Delirium, on the other hand, is an acute, or sudden onset of change in consciousness that can't be explained by a pre-existing dementia. Delirium can change or fluctuate over the course of a day, and can include changes in sleep patterns.
Even people with dementia can experience delirium; if a person with dementia demonstrates a rapid change in behavior or memory, delirium should be ruled out.
So what can cause delirium? There are several medical conditions that can cause delirium, including urinary tract infections, pneumonia, or even a mild heart attack. Medications can also cause symptoms of delirium.
Any time you see a sudden change in mental status of an older adult, be sure to consider some of the causes of delirium, and seek medical treatment.