Is educational attainment protective against developing dementia? A twin study of genetic and environmental contributions
Year: 2025
Type: article
Study design: Observational Study
Abstract: Low educational attainment is recognized as a modifiable risk factor for dementia. Despite the commonly accepted notion that greater educational attainment confers lower dementia risk, few family-based studies have investigated the causal bases for the association. Using data from seven twin samples from Sweden, Denmark, Australia, and the US participating in the IGEMS (Interplay of Genes and Environment in Multiple Studies) consortium (N = 60,027, 10.92% with dementia), we tested whether twins who achieve higher education than their co-twins have lower risk of dementia. The primary analysis applied a multilevel between-within regression framework, supported by descriptive statistics of within-pair differences. Results confirmed an overall association between educational attainment and dementia risk, such that individuals with higher educational attainment had less likelihood of developing dementia (phenotypic regression coefficient = -0.68, p <.0001). Within twin pairs, however, twins who achieved greater education than their co-twins did not uniformly show lower dementia risk (within-family regression coefficient = -0.07, p =.0983, while between-family regression coefficient = -0.98, p <.0001). Taken together, the pattern of results shows that the effect of educational attainment on dementia risk is largely attributable to genetic influences in common to educational attainment and dementia, although there are also contributions from environmental influences shared between members of the same family. Results were similar in men and women. These findings add to the literature by using a co-twin control design to address possible reasons that low educational attainment is associated with greater dementia risk.
Source: European Journal of Epidemiology
Authors: Ellen E. Walters, Susan E. Luczak, Christopher R. Beam, Malin Ericsson, William S. Kremen, Robert F. Krueger, Kristian E. Markon, Matt McGue, Marianne Nygaard, Matthew S. Panizzon, Brenda L. Plassman, Chandra A. Reynolds, Perminder S. Sachdev, Anbu Thalamuthu, Keith E. Whitfield, Nancy L. Pedersen, Margaret Gatz
Institutions: University of Southern California, Stockholm University, Karolinska Institutet, University of California San Diego, University of Minnesota, University of Southern Denmark, Duke University, University of Colorado Boulder, UNSW Sydney, Centre for Healthy Brain Ageing, Johns Hopkins University
Language: English
Subfield: Psychiatry and Mental health
Field: Medicine
Domain: Health Sciences
Open Access status: hybrid
Estimated APC paid: $3,690
Awards: G1870985794, Clarifying risk and protective factors for dementia with the Interplay of Genes and Environment in Multiple Studies (IGEMS) consortium, G2455682238, G3068190789, Oldest-old Mortality - Demographic Models and Analysis, G4241904236, G665544715, G738823225, Integrative Pathways to Health and Illness, G819432841, G8409209663, G8630433179, G9000067278, G9000074720, G9000080622, G9000118956, G9000251321, Integrative Pathways to Cognitive, Affective, and Brain Health, G978447472
OpenAlex ID: W4413108420