Life-course socioeconomic trajectories and cognitive aging in Chinese middle-aged and older adults

Socioeconomic positions (SEPs), operationalized by education, occupation, and income, are widely recognized determinants of cognitive function (CF). However, the effect of life-course SEP on cognitive aging remains inconclusive. This study investigated the impact of life-course SEP trajectories on later-life cognitive aging across SEP dimensions among Chinese adults born in the 1940s-70s who experienced distinct social mobility in the rapid social transformation.

We used data from the China Health and Retirement Longitudinal Study (2011-2020, 20 055 participants aged ≥45 years). Life-course SEP included early-life and adult education, occupation, and income. CF was measured as a composite cognitive score. Latent class analysis was conducted to identify heterogeneous SEP trajectory groups, and mixed-effects models were applied to estimate the impact of SEP trajectory on cognitive aging.

All life-course SEP indicators were positively associated with late-life CF, with adult SEP showing stronger impacts than childhood SEP. Upward mobility was notable in education (55.5%) and income (65.6%), whereas occupational transitions were relatively stable (68.0-71.3%). Participants with high early-life SEP and upward mobility had higher CF and slower decline than disadvantaged SEP trajectory groups, especially in women. Education and occupation trajectories had stronger impacts on cognitive aging than income trajectories.

Life-course SEP exerts protective effects on cognitive aging, with education and occupation showing stronger influences than income. Chinese women could gain greater cognitive benefits from SEP improvements than men. Optimizing lifelong SEP trajectories should be targeted as priorities to mitigate cognitive aging in developing countries.