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Innov Aging
Innov Aging
innovateage
Innovation in Aging
2399-5300 Oxford University Press US 

10.1093/geroni/igaa057.1661
igaa057.1661
Abstracts
Session 3015 (Paper)
Biobehavioral Health
AcademicSubjects/SOC02600
Cystatin C Trajectories Among Middle-Aged and Older Americans
Zhao Erfei 1 Crimmins Eileen 2 Ailshire Jennifer 2 Kim Jung Ki 3 Wu Qiao 2 1 
University of Southern California, Leonard Davis School of Gerontology, Los Angeles, California, United States
2 
University of Southern California, Los Angeles, California, United States
3 
University of Southern California, Los Angeles, United States
2020 
16 12 2020 
16 12 2020 
4 Suppl 1 Program Abstracts from The GSA 2020 Annual Scientific Meeting “Turning 75: Why Age Matters”514 515
© The Author(s) 2020. Published by Oxford University Press on behalf of The Gerontological Society of America.2020This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.Abstract
Deterioration in kidney functioning is associated with aging and is a major risk factor for mortality and other poor health outcomes. Medicare expenses for poor kidney functioning are about 100 billion dollars every year. High Cystatin-C is an indicator of poor kidney functioning. We do not know if cystatin-C increases gradually as an individual ages. We use the Health and Retirement Study 2006/2008 Biomarker sample with follow-up for 8 years to examine this. Demographic and socioeconomic differences in trajectories of Cystatin-C trajectories were examined for 22,984 participants aged 50 and older. Growth curve models reveal that, although Cystatin-C increases with age (beta=0.025, p<0.001), the annual increase varies by age (60-69 = 0.005, 70-79 = 0.013, 80+ = 0.017, p<0.001), controlling for other socioeconomic variables. Cystatin-C increases faster for males than females. Cystatin-C of non-Hispanic Whites is lower than non-Hispanic Blacks but higher than Hispanics; there is no racial/ethnic difference in change over time. People who spent fewer years in school have higher Cystatin-C, and college graduates have slower growth in Cystatin-C compared to people who did not graduate from high school. These novel findings highlight the disparities in the process of kidney aging among older Americans.