Project Summary/Abstract Over the past 15 years, substantial scientific advances have been made in understanding the links between the exposome and AD/ADRD risk factors. Yet Sub-Saharan Africa (SSA) remains a world region for which there is limited data and understanding around AD/ADRD prevalence and context-specific risk factors. The parent study (R01-AG077001) seeks to address this gap in research by establishing the Kenya Life Panel Survey (KLPS) as the premier SSA cohort for AD/ADRD life course risk factor research. The KLPS is a unique, richly phenotyped cohort of Kenyan adults who have been followed since childhood, and who were participants in a randomized child health intervention (school-based deworming). The existing dataset contains information on health, cognition, educational, demographic, social attitudes, and labor market outcomes for over 6,500 Kenyans first surveyed in 1998 (at ages 8-15) through 2021 (ages 31-39). KLPS thus provides an unusual opportunity to study cognition, and the determinants of AD/ADRD and related risk factors, over the life course, with direct measurement during childhood, young adulthood, and midlife. The KLPS Round 5 Aging Module (KLPS-5A) funded by the NIA parent grant collects detailed “midlife baseline” cognition measures aligned with the Harmonized Cognitive Assessment Protocol (HCAP) Network of studies, and aging-related health data, as well as information on AD/ADRD risk factors and exposure measures, among participants, who will be 35 to 43 years old at the time of survey. One novel aspect is the ability to link these midlife measures to existing data from childhood and early adulthood that was collected contemporaneously rather than via recall in later life. Another innovation is the ability to experimentally estimate the long-term effect of a child health intervention on AD/ADRD risk factors in midlife. The proposed administrative supplement is within scope of the parent grant, and will (a) enhance KLPS-5A with a significantly expanded and more comprehensive set of exposome measures of midlife (i) occupational complexity, job characteristics and work-related stress, (ii) social interactions and support, and (iii) air pollution exposure measures, all on the same sample of respondents, and will also (b) create public datasets, project materials, and data products on these exposome measures for use by others. The proposed measures capture salient and modifiable risk factors associated with AD/ADRD, which to date remain under-studied in this and other low- and middle-income contexts in SSA and elsewhere. In addition, these proposed measures capture risk factors that may have been influenced by the long-term effects of the child health intervention. The R01 parent study has planned to collect a partial set of these exposome measures; the administrative supplement will support an additional field survey interview dedicated to substantially expanding data collection along these dimensions, and will also...