Anxiety and risk of dementia: Systematic review and meta-analysis of prospective cohort studies

Objectives: Anxiety is postulated to be modifiable risk factor for dementia. Our primary aim was to conduct a meta-analysis of community-based cohort studies that investigated the association between anxiety and dementia. Design: We identified relevant, high-quality papers published up to January 2018 by searching PubMed and Web of Science. Prospective cohort studies reporting relative risks (RRs) for the association between anxiety and dementia, adjusted at least for age, were considered eligible. Study-specific RRs were combined using a random-effects model. Results: Six prospective cohorts (reported in 5 studies), with a total of 10,394 participants, were included in the meta-analysis. The pooled RR of 1.29 (95% CI: 1.01-1.66) indicated a significant association between anxiety and dementia. Conclusion: Anxiety significantly increases the risk of dementia. However, further research is needed to determine the extent to which anxiety is a cause of dementia rather than a prodrome or marker.