Abstract Body: Introduction: Few studies have examined the association of modifiable risk factors for dementia with cognitive performance and brain structure in early and middle adulthood, when underlying functional and structural changes in the brain may begin, and the potential for risk reduction and prevention is high.

Hypothesis: We hypothesized that cardiovascular risk factors are associated with cognitive performance and MRI-derived brain volumes in Hispanic/Latino individuals in early and middle adulthood (25-49 years of age).

Methods: We used data from the Hispanic Community Health Study/Study of Latinos (HCHS/SOL) and the SOL-INCA-MRI ancillary study. We included adults aged 25-49 years examined with cognitive tests at baseline (2008-2011, n=2330). These tests were z-score standardized and averaged to derive a global cognition (GC) score. We also included adults aged 35-49 years with MRI brain volumes quantified 10 years after baseline (2018-2022, n=219): total brain (TBV), total gray matter (TGMV), total cortical gray (TCGV), hippocampal (HV), and white matter hyperintensity (log-WMHV). These volumes were residualized to total cranial volume and z-score standardized. Cardiovascular risk factors measured at HCHS/SOL baseline for cognition and/or visit 2 (2014-2017) for brain volumes included self-reported smoking status, alcohol use level, diet quality (Alternative Healthy Eating Index 2010), and physical activity (Global Physical Activity Questionnaire), body mass index (BMI), systolic and diastolic blood pressure (mm Hg), fasting blood glucose (mg/dL), and non-HDL Cholesterol (mg/dL). We fitted survey linear regression models to test the association between cardiovascular risk factors and cognitive performance and brain volumes, accounting for sociodemographic factors.

Results: In multivariable regression models, current smoking (vs. never/former; GC: -0.10 [-0.17, -0.02]) and overweight status (vs. normal weight; GC: -0.11 [-0.21, -0.01]) were associated with lower cognitive performance. Current smoking status (vs. never/former; TGMV: -0.35 [-0.68, -0.03]), and higher diastolic blood pressure (TGMV: -0.02 [-0.03, -0.00]) were associated with smaller brain volumes and/or larger log-WMHV.

Conclusion: Modifiable risk factors, including smoking, overweight status, and high blood pressure, were associated with lower cognitive performance and/or smaller brain volumes in a relatively young Hispanic/Latino population.