biostudies-literatureWilliams EINational Institute for Health Research (NIHR)80-88https://www.ebi.ac.uk/biostudies/studies/S-EPMC12911656biostudies-literatureUnknown80(2)<h4>Background</h4>Socioeconomic status (SES) is a potentially important upstream determinant of late-life cognitive health, but a review which captures the dynamic influence of SES across the life-course is lacking. We conducted a systematic review of studies reporting associations between life-course SES and dementia/late-life cognitive decline.<h4>Methods</h4>On 21 February 2024, we searched Medline, Embase, PsycINFO, CINAHL, British Education Index, Web of Science, Scopus and Advanced Google for studies related to life-course SES and dementia. We included studies employing trajectory or mediation analysis that measured dementia/cognitive decline as outcomes. Two researchers independently screened articles and assessed risk of bias. Results were synthesised narratively and in Harvest plots.<h4>Results</h4>We included 18 out of 6040 studies screened (n=7 trajectory studies, n=8 mediation studies, n=3 both). Most (13/23) trajectory analyses reported that stable low SES and downward social mobility, relative to stable high SES/upward mobility, were linked to higher dementia and/or cognitive decline risk. Half (5/10) of the mediation analyses reported full mediation of adulthood SES on the association between childhood SES and dementia/cognitive decline, and 4/10 reported partial mediation. Overall, study quality was moderate.<h4>Conclusion</h4>SES has a dynamic life-course association with dementia risk. Increases in dementia risk are compounded by sustained life-course disadvantage. Policies to address socioeconomic disadvantage across the life-course are needed to address this upstream determinant of dementia.<h4>Prospero registration number</h4>CRD42024505975.Journal of epidemiology and community healthSystematic review of the association between life-course socioeconomic status and late-life cognitive decline.PMC12911656NIHR302276Walsh SKuhn IWilliams EIBrayne CEfalseSystematic review of the association between life-course socioeconomic status and late-life cognitive decline.<h4>Background</h4>Socioeconomic status (SES) is a potentially important upstream determinant of late-life cognitive health, but a review which captures the dynamic influence of SES across the life-course is lacking. We conducted a systematic review of studies reporting associations between life-course SES and dementia/late-life cognitive decline.<h4>Methods</h4>On 21 February 2024, we searched Medline, Embase, PsycINFO, CINAHL, British Education Index, Web of Science, Scopus and Advanced Google for studies related to life-course SES and dementia. We included studies employing trajectory or mediation analysis that measured dementia/cognitive decline as outcomes. Two researchers independently screened articles and assessed risk of bias. Results were synthesised narratively and in Harvest plots.<h4>Results</h4>We included 18 out of 6040 studies screened (n=7 trajectory studies, n=8 mediation studies, n=3 both). Most (13/23) trajectory analyses reported that stable low SES and downward social mobility, relative to stable high SES/upward mobility, were linked to higher dementia and/or cognitive decline risk. Half (5/10) of the mediation analyses reported full mediation of adulthood SES on the association between childhood SES and dementia/cognitive decline, and 4/10 reported partial mediation. Overall, study quality was moderate.<h4>Conclusion</h4>SES has a dynamic life-course association with dementia risk. Increases in dementia risk are compounded by sustained life-course disadvantage. Policies to address socioeconomic disadvantage across the life-course are needed to address this upstream determinant of dementia.<h4>Prospero registration number</h4>CRD42024505975.2026-01-01T00:00:00Z2026 Jan2026-07-09T13:14:28.189Z2026-07-09T13:10:12.354ZS-EPMC129116564113071810.1136/jech-2025-223864