Anxiety is associated with increased risk of dementia in older Swedish twins

Alzheimers Dement. 2016 Apr;12(4):399-406. doi: 10.1016/j.jalz.2015.09.008. Epub 2015 Nov 6.


Introduction: We asked whether anxiety is associated with prospective risk of dementia, and the extent to which genetic influences mediate this association.

Methods: Nondemented twins (n = 1082) from the Swedish Adoption Twin Study of Aging completed an assessment of anxiety symptoms in 1984 and were followed for 28 years.

Results: Baseline anxiety score, independent of depressive symptoms, was significantly associated with incident dementia over follow-up (hazard ratio [HR] = 1.04; 95% confidence interval [CI] = 1.01-1.06). There was 48% increased risk of becoming demented for those who had experienced high anxiety at any time compared with those who had not. In co-twin analyses, the association between anxiety symptoms and dementia was greater for dizygotic (HR = 1.11; 95% CI = 1.02-1.20) compared with monozygotic twins (HR = 1.06; 95% CI = 0.95-1.20), indicating genetic mediation.

Discussion: Anxiety symptoms were associated with increased risk of dementia. Genetic factors common to dementia and anxiety partially mediated this association.

Keywords: Anxiety; Dementia; Depression; Genetics; Twins.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Twin Study

MeSH terms

  • Aged
  • Anxiety / epidemiology*
  • Anxiety / genetics
  • Dementia / epidemiology*
  • Dementia / genetics
  • Female
  • Follow-Up Studies
  • Humans
  • Incidence
  • Male
  • Middle Aged
  • Prospective Studies
  • Psychiatric Status Rating Scales
  • Risk
  • Sweden
  • Twins, Dizygotic
  • Twins, Monozygotic