Is anxiety the first symptom of Alzheimer's?

Anxiety may be an early predictor of Alzheimer's in older adults, according to new research.  

As The Daily Mail reports, in a study of data on nearly 300 older adults, scientists from Brigham and Women's Hospital found that as the proteins associated with Alzheimer's disease built in people's brains, they tended to become more anxious.

Previous work has indicated that depression and other changes to mental health might be indicators of the disease before memory begins to deteriorate, but the new study honed in anxiety as the most closely linked symptom. 

The researchers hope that further research will bear out their discovery so that anxiety could become an early warning to begin monitoring patients for risk factors and early treatment of Alzheimer's disease. 

An estimated 5.5 million Americans are living with the brain and memory degeneration disease, Alzheimer's. 

Those numbers are only set to rise as our population ages. 

Though the exact cause of Alzheimer's still eludes scientists, clumps of chemically 'sticky' proteins, called beta-amyloids, stuck to neurons are a hallmark of the disease. 

The clumps, called plaques, are thought to interrupt signals in the brain, contributing to the loss of memory and cognitive functions in Alzheimer's patients.

Amyloid plaques start accumulating long before the most obvious, classic symptoms of Alzheimer's - particularly trouble recalling information - begin to appear in patients. 

Changes in personality and mood, however, are more subtle, but common markers of someone suffering from the disease. 

Past research has suggested that, even before memory loss begins, these changes in psychological state might be apparent.

In the new study, published in the American Journal of Psychiatry, the researchers compared self-reports on 30 symptoms of depression - including those related to anxiety - to images from brain scans that were able to show clusters of the protein plaques. 

Analyzing changes in both kinds of data over the course of five years, the team found that as brains became more clogged with the harmful proteins, anxiety increased as well, steeply than any of the other depression symptoms. 

'This suggests that anxiety symptoms could be a manifestation of Alzheimer's disease prior to the onset of cognitive impairment,' said first author Dr Nancy Donovan, a geriatric psychiatrist at Brigham and Women's Hospital.

Notably, research has shown that both Alzheimer's disease and anxiety disorders are more common in older people, and in women in the American population in general. 

'If further research substantiates anxiety as an early indicator, it would be important for not only identifying people early on with the disease, but also, treating it and potentially slowing or preventing the disease process early on,' Dr Donovan said.  

Follow NEWS.am Medicine on Facebook and Twitter