New research reveals that both chronic and new-onset anxiety are associated with a threefold increased risk of developing dementia later in life.
METHODOLOGY:
The study involved 2,132 participants aged 55-85 years (mean age, 76) from the Hunter Community Study, with a balanced gender distribution (53% women). Participants were assessed over three waves, spaced five years apart. Anxiety was measured using the Kessler Psychological Distress Scale (K10) at two points: baseline (wave 1) and first follow-up (wave 2). Anxiety was categorized as chronic (present in both waves), resolved (present only at wave 1), or new (appearing only at wave 2). The primary outcome, incident all-cause dementia, was identified using ICD-10 codes over a follow-up period of up to 13 years.
TAKEAWAY:
Out of the 2,132 cognitively healthy participants, 64 developed dementia, with an average time to diagnosis of 10 years. Chronic anxiety was linked to a 2.8-fold increased risk of dementia, while new-onset anxiety was associated with a 3.2-fold increased risk (P = .01). Participants under 70 years old with chronic anxiety had a 4.6-fold increased risk (P = .03), and those with new-onset anxiety had a 7.2-fold increased risk (P = .004). Anxiety that had resolved was not significantly associated with an increased risk of dementia.
Researchers speculate that anxiety might lead to unhealthy lifestyle behaviors, such as poor diet and smoking, which contribute to cardiovascular disease—a known risk factor for dementia.
IN PRACTICE:
Lead author Kay Khaing, MMed, from The University of Newcastle, highlights that “This prospective cohort study used causal inference methods to explore the role of anxiety in promoting the development of dementia. The findings suggest that anxiety may be a new risk factor to target in dementia prevention and that treating anxiety could potentially reduce this risk.”
LIMITATIONS:
The study’s reliance on the K10 for measuring anxiety, which assesses symptoms over the past four weeks, raises concerns about accuracy over the entire observation period. The overlap between anxiety and depression could lead to residual confounding. Additionally, the loss of 33% of participants to follow-up, who had higher baseline anxiety rates, may have led to missing cases of dementia and affected the risk estimates.
