Abstract Body (Do not enter title and authors here): Background: From 2018 to 2060 the proportion of US seniors (age 65+) will increase from 16% to 23%, with much of this growth driven by Hispanic/Latino seniors. Adverse social determinants of health (SDoHs) are drivers of poor health outcomes and accelerated aging.

Objective: To examine the association between SDoHs (education, income, and nativity) and aging speed among Hispanic/Latino adults.

Methods: The Hispanic Community Health Study/Study of Latinos is a longitudinal cohort of Hispanic/Latino adults from four US urban communities. Participants completed questionnaires, underwent clinic examinations, and provided biospecimens at visit 1 (V1: 2008-2011) and visit 2 (V2: 2014-2017). Education, income, and nativity were self-reported at V1. The Klemera-Doubal Method, an algorithm consisting of equations using biomarkers from different organ systems (waist-to-hip ratio, pulse pressure, lipids, glycosylated hemoglobin, alanine aminotransferase, cystatin C, and albumin-to-creatinine ratio), was used to calculate biological age (BA) among 5,316 females and 3,087 males ages 30 to 75 at either V1 or V2. Aging speed was defined as the difference between change in BA from V1 to V2 and follow-up time from V1 to V2. We used multivariable linear regression models to determine the sex-specific association between each SDoH with aging speed.

Results: At V1, mean chronological age was 47 years for females and 46 years for males. Over an average of six years, females aged biologically by 5 years and males aged biologically by 4 years. Compared with having more than a high school education, aging speed was greater by 0.69 years (95% CI: 0.45, 0.94) among females with less than a high school education but not among males (ß=0.57, 95% CI: -0.04, 1.17). Compared with an income ≥$50K, aging speed was greater by 0.67 years (95% CI: 0.30, 1.04) among females with an income <$30K but not among males (ß=0.62, 95% CI: -0.08, 1.31). Compared to those born in the 50 US states/DC, being foreign born was associated with slower aging speed by 0.39 years (95% CI: -0.72, -0.06) among females but not among males (ß=0.52, 95% CI: -0.35, 1.39).

Conclusion: Over six years, Hispanic/Latino males and females demonstrated slower biological aging compared with chronological aging. Lower income, lower educational attainment, and being born in the 50 US states/DC were associated with greater biological aging (faster aging speed) among Hispanic/Latino females.