Older Adults With Anxiety May Be at Higher Risk for Dementia

Anxiety in older adults may triple the risk of dementia from any cause. In a new study of more than 2,000 Australians between ages 55 and 85, researchers also found that new anxiety was associated with a greater likelihood of later dementia.

But people whose anxiety has “resolved” — that is, who had anxiety at one time but no longer do — had the same risk level as people who never reported having anxiety.

“We found that experiencing anxiety at age 70 or younger increased the risk of dementia,” says the lead author of the study, Kay Khaing, a conjoint lecturer and researcher at the School of Medicine and Public Health at the University of Newcastle, Australia.

These findings highlight the importance of anxiety awareness and anxiety management in middle-age and older adults to potentially prevent dementia, says Khaing.

1 in 6 Older Adults Have Anxiety

It’s estimated that between 14 and 17 percent of people 65 and older have an anxiety diagnosis. Many experts believe that’s actually a significant undercount, because many cases are missed.

And few older adults with a diagnosed anxiety disorder get treated for it. For example, experts estimate that only about one-third of people in this age group with generalized anxiety disorder (GAD) receive any mental health care.

Chronic and New Anxiety Triple the Risk of Later Dementia

To explore the ways that anxiety impacts the risk of developing any type of dementia, researchers recruited more than 2,000 individuals with an average age of 76 years who were participating in the Hunter Community Study in Australia.

People were followed for 10 years and placed into one of three categories: chronic anxiety, new onset anxiety during the follow-up period, and resolved anxiety.

Chronic anxiety (reported when the study started and in the follow-up period) and new onset anxiety (anxiety that was reported during the study) were associated with 2.8- and 3.2-times higher risks of dementia, respectively, than no anxiety.

For people with resolved anxiety, dementia risk was nearly the same as people who never reported anxiety.

The link between anxiety and dementia risk was particularly strong in participants ages 70 years and younger. For this group, those with chronic anxiety were four times more likely to develop dementia, and people with new onset anxiety were more than seven times more likely.

Study Doesn’t Prove That Anxiety Causes Dementia

Because the study was observational rather than an intervention, the findings can only suggest a link or association. They don’t prove that anxiety increases dementia risk.

It would not be ethical to perform a randomized trial in which some people had untreated anxiety, noted the authors.

The findings echo those of a meta-analysis of eight studies that looked at the association between anxiety and dementia and found a significant association.

Should Anxiety Be Considered a Risk Factor for Dementia?

“The findings suggest that anxiety may be a new risk factor to target in the prevention of dementia and also indicate that treating anxiety may reduce this risk,” says Khaing.

Richard Marottoli, MD, MPH, a Yale Medicine geriatrician and a professor of medicine at Yale School of Medicine in New Haven, Connecticut, agrees that in theory, the findings suggest that improving anxiety symptoms may lower dementia risk. (Dr. Marottoli was not involved with the new research.)

“However, we cannot tell this from the available data, as we do not know why they were anxious in the first place or why it was resolved,” he points out. “It may have just been related to factors going on at the time of the original assessment that resolved quickly as opposed to persisting factors.”

Does Having Anxiety as a Younger Adult Impact Dementia Risk?

The people in this study were between 55 and 85 years old. Would having anxiety as a younger adult be associated with later dementia risk? Both Khaing and Marottoli agree that these findings can’t be applied to a younger group.

It’s possible that anxiety in younger people may affect dementia risk in later life, but a future study (with a much longer follow-up) would be needed to know that, says Khaing.

“There is no way to assess or extrapolate this from this data. There may be very different contributors to anxiety at a younger age than in the population studied here,” says Marottoli.

The Bottom Line: People With Persistent Anxiety Should See a Healthcare Professional

“Persistent anxiety symptoms may have longer-term health effects, and one should seek medical help to identify potential contributing factors and strategies to help cope with or resolve both the contributing factors and one’s response to them,” says Marottoli.