Chronic, new anxiety may increase risk for dementia, but anxiety resolution negates risk

Key takeaways:

• Patients with chronic anxiety and new anxiety were approximately three times more likely to develop dementia.
• Participants with resolved anxiety did not demonstrate an increased dementia risk.

New and chronic anxiety were associated with an increased risk for all-cause dementia, especially among individuals aged 70 years and younger, according to a study published in Journal of the American Geriatrics Society.

Kay Khaing

However, patients with resolved anxiety upon follow up had a lower dementia risk that was comparable to patients who had never been exposed to anxiety.

“The findings highlight the role of anxiety in dementia risk and the importance of successful management of anxiety in reducing dementia risk,” Kay Khaing, MMed, conjoint lecturer with the School of Medicine and Public Health at the University of Newcastle in Australia, told Healio. “These findings empower clinicians to raise awareness of anxiety among their patients and focus on managing anxiety in order to reduce the risk of dementia.”

Previous studies on the relationship between anxiety and dementia did not address the impact of chronicity of anxiety or the timing of a patient’s first exposure to anxiety on dementia risk, according to the researchers.

This knowledge deficit motivated Khaing and colleagues to perform a longitudinal analysis evaluating both timing of exposure as well as whether anxiety was chronic, resolved or new onset regarding risk for all-cause dementia.

The analysis included 2,132 individuals aged 55 to 80 years (53% female; mean age, 76 years) from the Hunter Community Study who did not have dementia at baseline. The researchers measured anxiety and depression using the Kessler Psychological Distress Scale (K10) at wave 1 and again 5 years later at wave 2. They categorized temporal differences in anxiety as chronic (present at both wave 1 and 2), resolved (wave 1 only) and new (wave 2 only).

Incident all-cause dementia during follow up served as the study’s primary outcome.

The researchers used the Fine and Gray regression model to estimate the probability of incident dementia with death as the competing event over time and conducted three different analyses: one that controlled for social demographic data (model 1), one that controlled for cofounder variables, including depression (model 2) and a sensitivity analysis that addressed reverse causation by excluding deaths and dementia that occurred in the first 5 years.

Overall, 21% of participants had anxiety at baseline/wave 1.

Over the mean follow-up period of 10 years, 64 patients (3%) developed dementia with an average onset of 10 years and 151 patients (7%) died.

Results showed a significantly increased risk for all-cause dementia associated with chronic anxiety (model 1: HR = 2.57; 95% CI, 1.27–5.2; model 2: HR = 2.8; 95% CI, 1.35– 5.72) and new anxiety (model 1: HR = 3.2; 95% CI, 1.37–7.43; model 2: HR = 3.2; 95% CI, 1.4–7.45). However, participants with resolved anxiety did not appear to be at increased risk (model 1: HR = 1.02; 95% CI, 0.41–2.55; model 2: HR = 1.06; 95% CI, 0.4–2.81).

When Khaing and colleagues evaluated the data based on age, they found that participants aged 70 years and younger who presented with chronic anxiety (HR = 4.58; 95% CI, 1.12–18.81) and new anxiety (HR = 7.21; 95% CI, 1.86–28.02) had an increased risk for dementia, but this finding did not persist in other age groups.

In the sensitivity analysis, the researchers also found an increased risk for all-cause dementia with chronic anxiety (HR = 2.94; 95% CI, 1.42–6.11) and new anxiety (HR = 2.8; 95% CI, 1.16–6.78). Again, resolved anxiety did not have a significant association with dementia (HR = 1.1; 95% CI, 0.41–2.92).

Khaing and colleagues noted several limitations to their study, including that they may have missed some patients with dementia and that the K10 assessment only asks about anxiety within the past 4 weeks. Also, 33% of patients with baseline anxiety were lost to follow up.

It was not surprising that the results suggested an association between chronic and new anxiety and increased dementia risk, due to anxiety’s link to dementia pathology, Khaing told Healio.

“However, [our finding] that resolved anxiety decreased the risk of dementia was unexpected,” she said.

Future studies should investigate the effects of different types (pharmacological and nonpharmacological) and length of anxiety treatments on dementia risk, she added.

Reference:

• Can anxiety increase the risk of developing dementia? https://newsroom.wiley.com/press-releases/press-release-details/2024/Can-anxiety-increase-the-risk-of-developing-dementia/default.aspx. Published July 24, 2024. Accessed July 24, 2024.