title: Anxiety as a Predictor for Cognitive Decline and Dementia: A Systematic Review and Meta-Analysis.
abstract: Because anxiety is postulated as a risk factor for dementia, we performed a systematic review and meta-analysis to investigate whether anxiety predicts cognitive decline and/or dementia, taking the stage of cognitive decline as well as setting into account.
  
  
  
  A systematic literature search up to January 2015 was performed to identify all longitudinal studies on the association between anxiety and cognition. Data extraction and methodological quality assessment were conducted independently by two authors. Where possible, pooled relative risks were calculated to examine anxiety as a possible risk factor for cognitive decline cognitive impairment and dementia in community studies (objective 1), as well as for conversion to dementia patients referred to memory clinics (objective 2).
  
  
  
  Twenty studies met inclusion criteria. Data on cognitive decline were too heterogeneous for meta-analysis. Anxiety predicted incident cognitive impairment (4 studies, relative risk [RR]: 1.77, 95% confidence interval [CI]: 1.38-2.26, z = 4.50, p < 0.001) and dementia (6 studies, RR: 1.57, 95% CI: 1.02-2.42, z = 2.05, p = 0.040) in the community, the latter driven by studies with a mean age of 80 years or above. Among clinical mild cognitive impairment samples, anxiety did not predict conversion to dementia (RR: 1.21, 95% CI: 0.90-1.63, z = 1.28, p = 0.200).
  
  
  
  Anxiety is associated with an increased risk for cognitive impairment and dementia in the community. Stronger associations were driven by higher age, suggesting that it is a prodromal symptom. Causal biological pathways have also been described, which could explain the risk for incident cognitive impairment in the community. Future studies should include mediating mechanism when studying anxiety as a predictor for cognitive decline and/or dementia.
authors: Regional Institute for Mental Health Care in Outpatients, RIAGG Maastricht, Maastricht, The Netherlands; Department of Psychiatry and Psychology / MUMC, School for Mental Health and Neuroscience (MHeNS) / Alzheimer Centre Limburg, Maastricht University Medical Center, Maastricht, The Netherlands. Electronic address: bgulpers.uop@gmail.com.
authors: Bernice
authors: B
authors: Gulpers
authors: Department of Psychiatry and Psychology / MUMC, School for Mental Health and Neuroscience (MHeNS) / Alzheimer Centre Limburg, Maastricht University Medical Center, Maastricht, The Netherlands.
authors: Inez
authors: I
authors: Ramakers
authors: Department of Psychiatry and Psychology / MUMC, School for Mental Health and Neuroscience (MHeNS) / Alzheimer Centre Limburg, Maastricht University Medical Center, Maastricht, The Netherlands.
authors: Renske
authors: R
authors: Hamel
authors: Department of Psychiatry and Psychology / MUMC, School for Mental Health and Neuroscience (MHeNS) / Alzheimer Centre Limburg, Maastricht University Medical Center, Maastricht, The Netherlands.
authors: Sebastian
authors: S
authors: Köhler
authors: Center for Psychiatry & Interdisciplinary Center of Psychopathology of Emotion Regulation (ICPE), University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
authors: Richard
authors: R
authors: Oude Voshaar
authors: Department of Psychiatry and Psychology / MUMC, School for Mental Health and Neuroscience (MHeNS) / Alzheimer Centre Limburg, Maastricht University Medical Center, Maastricht, The Netherlands.
authors: Frans
authors: F
authors: Verhey
mesh_terms: D001007:Anxiety / Q000453:epidemiology*; D001008:Anxiety Disorders / Q000453:epidemiology*; D060825:Cognitive Dysfunction / Q000453:epidemiology*; D003704:Dementia / Q000453:epidemiology*; D006801:Humans; D012307:Risk Factors
keywords: Dementia; anxiety; cognition; cognitive decline; meta-analysis; review; risk factor