Risk and Resilience Factors in Memory Aging Among Older Cancer Survivors: A Cross Country Comparison of the US and England - Memory loss is a hallmark symptom of Alzheimer’s disease and related dementias (ADRD). By identifying its early stages, interventions could be developed to prevent or slow ADRD progression. While previous research has examined memory aging among the general population, the long-term memory aging of older cancer survivors is under-studied. This is a critical evidence gap, as >26 million people in the United States (US) and >5 million people in the United Kingdom (UK) will be cancer survivors by 2040, and >70% of cancer survivors will be over age 65. The US and UK have different health care systems, government social safety net policies, and magnitudes of income inequality. Hence, older cancer survivors are aging in different social, political, and economic environments across these two high-income countries. A cross-national comparison of the US and UK is an opportunity to identify drivers of both individual-level variation and population-level differences in the memory aging of older cancer survivors. Understanding the long-term memory aging of older cancer survivors in a cross-national framework will enhance our knowledge of what factors matter most for the memory aging of older cancer survivors and could be targets for interventions. This K99/R00 proposal leverages longitudinal pre- and post-cancer diagnosis data from two nationally representative cohorts, the US Health and Retirement Study (HRS) and the English Longitudinal Study of Ageing (ELSA), to investigate long-term memory trajectories of N=2,500 older cancer survivors from 2002 to 2018. The specific aims are to: (1) identify and compare memory trajectories of cancer survivors in the HRS and ELSA, overall and by age and sex (K99 phase); (2) identify and compare individual, neighborhood, and macro-level socioeconomic inequalities in memory aging of cancer survivors in the HRS and ELSA (R00 phase); and, (3) identify the roles of modifiable risk and resilience factors (hypertension, diabetes, obesity, depression, physical activity, social support) across countries, as these may be intervention targets to promote healthy memory aging among older cancer survivors (R00 phase). The training plan will build on the applicant’s prior training in social and cancer epidemiology to include: (1) ADRD research among cancer survivors; (2) the measurement and analysis of multi-level socioeconomic exposures; (3) and complex longitudinal data analyses in a cross-national framework. This integrated training will prepare the applicant for a successful independent research career focused on the social determinants of healthy aging among older cancer survivors. The applicant is supported by a cohesive and interdisciplinary mentorship team, including HRS and ELSA leadership. Identifying country-level differences in risk and resilience for cancer-related memory aging is important for informing population-level interventions and will support the exploration of policy- relevant determinants in future research. The proposed research will unite the fields of cancer survivorship and ADRD research by using a cross-national, population-based approach to identify high-risk groups of older cancer survivors for accelerated memory decline, as well as identify modifiable risk factors as intervention targets.