Traumatic life events and risk for dementia: a systematic review and meta-analysis

ObjectivesTo systematically review the association between traumatic life events (TLE) and dementia risk.DesignSystematic review and meta-analysis.Data sourcesAPA, PsychINFO, Embase and MEDLINE from their inception to 29.05.21 and updated on 20.04.22.Eligibility criteria for selecting studiesOriginal research articles published in peer reviewed journals examining the association between TLE and all cause dementia in individuals aged 60 and over. Two researchers independently assessed the risk of bias using the Newcastle-Ottawa Scale. We conducted a generic inverse variance random effects meta-analysis to provide an overall estimate of TLE impact on dementia risk.Main outcome measuresRisk, odds and hazards ratios relating to dementia risk.ResultsInitially, 3,487 studies were retrieved in the search and seven studies were included in the meta-analysis with data being used from 276,570 participants. TLE were associated with increased dementia risk. Trauma in general had a pooled HR of 1.21, (95% CI 1.03, 1.43, P = 0.0001). War/ Holocaust trauma and childhood trauma were also associated with increased dementia risk (HR = 1.28 (95% CI 1.01-1.63, P = 0.02) and HR = 1.76 (95% CI 1.17-2.64, P = 0.007) respectively).ConclusionsWe have found an association between TLE and dementia risk. Future research exploring the dimensions of TLE and individual level factors are needed to better understand the relationship between TLE and dementia.Trial RegistrationPROSPERO CRD42021253090.