While memory problems are the most widely known symptoms of Alzheimer's disease, this form of dementia also causes neuropsychiatric symptoms called Behavioral and Psychological Symptoms of Dementia (BPSD). These symptoms include anxiety, apathy, depression, hallucinations, paranoid, and sundowning (restlessness or agitation that worsens as daylight begins to fade).
Researchers from the Institute of Neuroscience of the Universitat Autònoma de Barcelona (Inc-UAB) in Spain and the Karolinska Institutet (KI) in Sweden looked at the long-term effects of caffeine consumption with normal aging mice and familial Alzheimer's models.
Earlier research has shown that caffeine may help prevent dementia because of its ability to block adenosine receptors, which may cause dysfunctions and disease in old age. However, for people who already have Alzheimer's disease, caffeine intake may not be beneficial and may even cause negative effects.
For the study, the researchers treated mice with either water or a very low dose of caffeine (0.3 milligrams per milliliter [mg/mL]) from adulthood until middle age (ages six to 13 months). The amount of caffeine given to mice is equivalent to three cups of coffee for humans.
The results showed that caffeine changed the behavior of healthy mice and worsened the neuropsychiatric symptoms of mice with Alzheimer's disease, particularly in relation to anxiety-related behaviors, emotional and cognitive flexibility, and neophobia (an extreme fear of everything new).
The increase in neophobia and anxiety-related behaviors in mice with Alzheimer's disease made their BPSD-like profile worse. The researchers said that these adverse effects of caffeine, such as anxiety, may also affect the beneficial cognitive effects of caffeine, which include learning and memory.
"These results are relevant when coffee-derived new potential treatments for dementia are to be devised and tested," explained Lydia Giménez-Llort of the Inc-UAB, lead researcher of the study.
Alzheimer's disease is the most common form of dementia, accounting for 60 to 80 percent of dementia cases. While anyone can develop the disease, it is more prevalent among the elderly, or those aged 65-years-old and older. Those who are diagnosed with Alzheimer's disease before the age of 65 are said to have early-onset Alzheimer's disease. (Related: Unlock the secrets to preventing Alzheimer's and Dementia... (yes, we have the solutions))
Alzheimer's disease is a progressive disease, which means that it worsens with time. Its symptoms manifest gradually and the effects on the brain cause a slow decline.
Although there is no known cure for Alzheimer's disease yet, there are therapeutic treatments that can make the lives of people with Alzheimer's disease easier. Dementia care must have the following elements:
Alzheimer's disease affects people differently. There are people who live a long time with mild cognitive impairment, while there are some who experience a faster development of symptoms and a more rapid disease progression.
Read more news stories and studies on Alzheimer's disease by going to Alzheimers.news.