A new study discovers that people with mild cognitive impairment (MCI) are at increased risk of Alzheimer’s disease within a few years. And the risk of Alzheimer’s increases significantly if they suffer from anxiety.
Researchers at Baycrest Health Sciences’ Rotman Research Institute in Toronto, Canada, determined that anxiety symptoms in individuals diagnosed with MCI significantly increases the risk of a speedier decline in cognitive functions. This finding was independent of depression which is an additional risk factor.
For MCI patients with mild, moderate, or severe anxiety, Alzheimer’s risk increased by 33 percent, 78 percent, and 135 percent respectively.
The research team also found that MCI patients who had reported anxiety symptoms at any time over the follow-up period had greater rates of atrophy in the medial temporal lobe regions of the brain. This brain area is essential for creating memories and is an brain region often implicated in Alzheimer’s.
The findings were published online by The American Journal of Geriatric Psychiatry, ahead of print publication.
Experts say that until now, anxiety as a potentially significant risk marker for Alzheimer’s in people diagnosed with MCI has never been clearly studied.
There is a growing body of literature that has identified late-life depression as a significant risk marker for Alzheimer’s.
The distinction is important as anxiety has historically tended to be subsumed under the rubric of depression in psychiatry. Depression is routinely screened for in assessment and follow-up of memory clinic patients; anxiety is not routinely assessed.
“Our findings suggest that clinicians should routinely screen for anxiety in people who have memory problems because anxiety signals that these people are at greater risk for developing Alzheimer’s,” said Dr. Linda Mah, principal investigator on the study.
“While there is no published evidence to demonstrate whether drug treatments used in psychiatry for treating anxiety would be helpful in managing anxiety symptoms in people with mild cognitive impairment or in reducing their risk of conversion to Alzheimer’s, we think that at the very least behavioral stress management programs could be recommended.
“In particular, there has been research on the use of mindfulness-based stress reduction in treating anxiety and other psychiatric symptoms in Alzheimer’s — and this is showing promise,” said Mah.
The Baycrest study accessed data from the large population-based Alzheimer’s Disease Neuroimaging Initiative to analyze anxiety, depression, cognitive, and brain structural changes in 376 adults, aged 55-91, over a three-year period.
Those changes were monitored every six months. All of the adults had a clinical diagnosis of amnestic MCI and a low score on the depression rating scale, indicating that anxiety symptoms were not part of clinical depression.
MCI is considered a risk marker for converting to Alzheimer’s disease within a few years. However, not all MCI sufferers will convert to Alzheimer’s; some will stabilize and others may even improve in their cognitive powers.
“The Baycrest study has yielded important evidence that anxiety is a ‘predictive factor’ of whether an individual with MCI will convert to Alzheimer’s or not,” said Mah.
Studies have shown that anxiety in MCI is associated with abnormal concentrations of plasma amyloid protein levels and T-tau proteins in cerebrospinal fluid, which are biomarkers of Alzheimer’s.
Depression and chronic stress have also been linked to smaller hippocampal volume and increased risk of dementia.