COGNITIVE changes linked to Alzheimer’s risk factors, including cardiovascular health, immune markers, and neurodegenerative biomarkers, emerge as early as age 24, decades before clinical symptoms appear, according to a landmark U.S. study.
Alzheimer’s disease, traditionally viewed as a condition of older age, may begin influencing cognitive function far earlier than previously recognised. A Columbia University-led study of over 11,000 participants aged 24–44 reveals that cardiovascular risk factors, immune markers, and Alzheimer’s-associated biomarkers correlate with memory performance even in young adulthood. These findings challenge the conventional focus on older populations, emphasising the need for early preventive strategies to mitigate long-term cognitive decline.
Analysing data from the National Longitudinal Study of Adolescent to Adult Health (Add Health), researchers assessed Cardiovascular Risk Factors, Aging, and Incidence of Dementia (CAIDE) scores, APOE ε4 status, and biomarkers including tau, neurofilament light (NfL), and inflammatory markers. In participants aged 24–34 (Wave IV), each 1-point CAIDE score increase corresponded to a 0.03 standard deviation reduction in backward digit span performance (95% CI: −0.04, −0.02). By ages 34–44 (Wave V), elevated tau levels showed a stronger association with immediate word recall (β = −0.13, 95% CI: −0.23, −0.04), while interleukin-6 (IL-6) and IL-8 linked to poorer cognitive scores. Notably, APOE ε4 – a key genetic risk factor – did not significantly affect cognition in this age group, suggesting its role may emerge later.
These results underscore the critical importance of early-life interventions targeting cardiovascular health, inflammation, and neurodegenerative pathways to reduce Alzheimer’s risk. Clinicians should consider integrating risk factor monitoring into routine care for younger adults, particularly those with elevated CAIDE scores or inflammatory markers. Future research must explore targeted interventions, such as lifestyle modifications or anti-inflammatory therapies, to disrupt these early pathological processes.
Reference
Aiello AE et al. Risk factors for Alzheimer’s disease and cognitive function before middle age in a US representative population-based study. The Lancet Regional Health–Americas. 2025;DOI:10.1016/j.lana.2025.101087.
