Anxiety Increases Risk of Developing Alzheimer’s Disease In Some

The dangers associated with anxiety have long been reported. Heart disease, hypertension, diabetes, depression, gastrointestinal problems, obesity and even asthma have even been linked to increased levels of anxiety and stress. You don’t have to be diagnosed with Generalized Anxiety Disorder (GAD) to experience the effects of, or even some aspects of, the disease.  With all of the factors weighing upon individuals in society today, the likelihood of experiencing a bout of stress, or even anxiety, is fairly high.

Anxiety does not discriminate either. People of all ages, races and socioeconomic levels are prone to experience it. Ideally, one isn’t likely to be stuck in a chronic cycle of anxiety and can rebound from it. However, there are many contributing factors, which increase one’s risk of sustaining their level of anxiety.  Medication and therapy are available to help people though a crisis. But what goes on in the body during that enhanced period of stress can be life altering, not just mentally, but physically as well. 

The Beginning of The Study

A recent study out of Baycrest Health Sciences’ Rotman Research Institute in Toronto, Canada, found that anxiety symptoms in individuals diagnosed with mild cognitive impairment (MCI) had a significantly increased risk of a speedier decline in cognitive functions. Depression was also found to increase the risk as well, independent of the anxiety.  Anxiety symptoms in amnestic MCI (aMCI) patients were found to more quickly develop Alzheimer’s Disease (AD) over and beyond the effects of depression, memory loss, or atrophy alone.

These findings, together with the greater entorhinal cortical (EC) atrophy rate predicted by anxiety, help conclude that anxiety is not an early symptom or a non-cognitive feature of Alzheimer’s. It may, however, accelerate the patient’s decline towards AD through direct or indirect effects on EC volumes in the brain.  Studies also show anxiety in MCI is associated with abnormal concentrations of plasma amyloid protein levels and T-tau proteins in cerebrospinal fluid, which are biomarkers of AD.

The Results

The Baycrest study gathered data from the large population-based Alzheimer’s Disease Neuroimaging Initiative, to analyze anxiety, depression, cognitive, and changes in brain structure in 376 adults, aged 55-91, over a three-year period.  The results were significant. For MCI patients with mild, moderate, or severe anxiety, Alzheimer’s risk increased by 33 percent, 78 percent, and 135 percent respectively showing that anxiety severity increased the rate of amnestic MCI conversion to AD, after controlling for depression and cognitive decline.  Patients were evaluated every six months and any changes were noted. All of the adults had a clinical diagnosis of aMCI but did have a low score on the depression rating scale, indicating that anxiety symptoms were not part of clinical depression. 

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 is the area of the brain essential for creating memories and is often connected with Alzheimer’s.  There is, however, an increasing amount of research available that has identified depression in this population to be a significant risk marker for Alzheimer’s as well. Whereas, depression is routinely screened for in the assessment and follow-up of memory clinic patients, anxiety is not routinely assessed.

Generally, anxiety has often been catalogued with psychiatry and not considered as its own category. The distinction between whether the patient has anxiety, depression or both is obviously important.  A principal investigator on the study, Dr. Linda Mah states, “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.” Further, “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,” said Mah.

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.

Conclusion:  Anxiety may accelerate the patient’s decline towards Alzheimer's Disease through direct or indirect effects on the brain.

The American Journal of Geriatric Psychiatry published the study’s findings online, ahead of the print publication, which is scheduled for May 2015.

- Laura A. Wells

Baycrest Centre for Geriatric Care. (2014, November 10). Anxiety can damage brain, research shows. ScienceDaily. Retrieved November 24, 2014 from www.sciencedaily.com/releases/2014/11/141110124352.htm

Mah, L., Binns, M., Steffens, D. (2014, October 29). Anxiety symptoms in amnestic mild cognitive impairment are associated with medial temporal atrophy and predict conversion to Alzheimer’s disease. The American Journal of Geriatric Psychiatry. Retrieved November 24, 2014 from http://www.ajgponline.org/article/S1064-7481(14)00306-6/abstract

Nauert, R. (Ed.). (2014, November 11). Anxiety Increases Risk of Alzheimer's Disease. Retrieved November 24, 2014, from http://psychcentral.com/news/2014/11/11/anxiety-increases-risk-of-alzheimers-disease/77203.html