Measuring stress and epigenetic aging among Black older adults in longitudinal studies of aging

Stress is a fundamental pathway to variation in health and aging. African American older adults experience more stressors over their life course and age faster than other groups as evidenced by earlier onset of most diseases and declines in biological, physical and cognitive functioning. One of the underlying mechanisms connecting stress to multiple age-related diseases is epigenetic changes, now termed one of the “hallmarks of aging.” A myriad of national data sets have invested time and money in collecting DNA methylation (DNAm)—a common measure of epigenetic changes—in multiethnic samples, providing mechanistic insights into an individual’s molecular response to environmental stressors that underlie disease processes and inform our understanding of the biological processes through which differences in health manifest. Integrating epigenetics into population-level health research is important given the unequal, and rapid aging of populations and the huge investment in DNAm across different study designs, ethnic groups, ancestries, and at different ages. The proposed project compares the stress, anthropometric, biological, and epigenetic age profiles of African American and African ancestry older adults across age cohorts (young-old and long-lived) in both the Health and Retirement Study (HRS) and the Study of Longevity and Stress in African American Families (SOLSAA). Sitting at the cusp of the genomic data revolution, this proposal will ensure I get the training I need as a biosocial gerontologist to work independently with social stress, biosocial, and epigenetic data across distinct data sets of older African American adults and fulfill the objectives outlined in this proposal. Through the K01 Career Development Award, I will combine my extensive experience studying disparities in stress and aging and will gain additional training in molecular biology, bioinformatics, epidemiology, epigenetic mechanisms, bioethics and professional development. The University of Southern California (USC) Leonard Davis School of Gerontology is an ideal location to receive the skills needed during the training phase given its multidisciplinary nature and connection to USC|UCLA Center for Biodemography and Population Health and USC Alzheimer’s Disease Related Dementias Resource Center ADRD and extended networks in Southern California for coursework and mentorship. Completion of the training and research aims will result in scientific presentations and publications, preliminary data to successfully compete for R01 funding that integrates longitudinal DNAm data (currently being collected) in longitudinal cohort studies of aging with life course stress and longitudinal health outcomes. This project will improve measures of aging, providing a more accurate picture of the aging experience. This study will also support a paradigm shift in aging research, combining medical frameworks with social stress frameworks that challenge traditional narratives of health, improve our understanding of aging, and support insight for the planning of aging resources among African American and African ancestry populations.