Jan Sebastian Novotný, Sivan Klil-Drori, Yonas Endale Geda, Ziad Nasreddine, Gorazd Bernard Stokin
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引用次数: 0
Abstract
Background: Population ageing is driving a global surge in cognitive impairment. While late-life decline is well-characterized, the onset of measurable cognitive changes across the full adult lifespan remains uncertain. We aimed to estimate the age at which detectable decline begins using longitudinal data from three population-based cohorts from three countries spanning three continents.
Methods: We analyzed participant-level longitudinal data from the China Health and Retirement Longitudinal Study (CHARLS; China), Midlife in the United States (MIDUS; USA), and Kardiovize (KV; Czech Republic). Cognitive performance was assessed using validated instruments (TICS, BTACT, and MoCA). Scores were harmonized using the percent of maximum possible method (0-100 metric). Linear mixed-effects models, adjusted for age group, sex, and education estimated change over an average 7-9-year follow-up.
Findings: In pooled sample of 14,389 participants (baseline age 22-94 years), a detectable decline in total cognition first emerged in the 31-40 age group (mean change -1.2 points, 95% CI -2.1 to -0.3). Decline magnitude increased progressively with age, reaching -11.4-points in the oldest strata (all p<0.001). Non-memory domains showed earlier vulnerability (detectable from age 31), while significant memory decline emerged after age 50. Individual trajectories showed substantial heterogeneity, suggesting that chronological age is not a deterministic proxy for decline.
Interpretation: Population-level cognitive decline became detectable in early midlife, decades before the traditional clinical focus on older age. Across three population-based cohorts from Asia, North America, and Europe, we observed consistent early decline in non-memory domains followed by later memory decline. These findings support evaluation of midlife cognitive monitoring and life-course approaches to brain health.
Funding: European Union Next Generation EU; European Regional Development Fund; European Social Fund; Barrow Neurological Foundation; NIH.
期刊介绍：
The JPAD Journal of Prevention of Alzheimer’Disease will publish reviews, original research articles and short reports to improve our knowledge in the field of Alzheimer prevention including: neurosciences, biomarkers, imaging, epidemiology, public health, physical cognitive exercise, nutrition, risk and protective factors, drug development, trials design, and heath economic outcomes.JPAD will publish also the meeting abstracts from Clinical Trial on Alzheimer Disease (CTAD) and will be distributed both in paper and online version worldwide.We hope that JPAD with your contribution will play a role in the development of Alzheimer prevention.
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