Education and age of decline in verbal memory across countries: Evidence from the HRS, MHAS, and CHARLS.

Background: Despite the well-established association between education and cognition in old age, age-related changes in cognition by education across different contexts remain underexplored. Objective: This study investigates cross-national differences in decline in verbal memory among adults aged 50 and older in the United States, Mexico, and China. Methods: Data come from the Health and Retirement Study (HRS, 2012-2020), Mexican Health and Aging Study (MHAS, 2012-2021), and China Health and Retirement Longitudinal Study (CHARLS, 2011-2020). Multilevel models estimated changes in verbal memory across six age groups and six educational levels, adjusting for physical health, residence, and gender. Results: HRS participants had the highest educational attainment, while CHARLS participants had the lowest. Higher education was associated with better verbal memory, with the most pronounced education gradient in the CHARLS. Declines in verbal memory were steeper for MHAS and CHARLS participants over 60 compared to HRS participants. MHAS participants experienced earlier declines in verbal memory across all education levels compared to HRS and CHARLS participants. Conclusions: Middle-aged and older adults in Mexico experienced earlier declines in verbal memory after age 50 compared to those in China and the United States. Future research should seek to identify other potentially modifiable factors that may contribute to cross-national differences in decline in verbal memory.