Latinos are the fastest growing subpopulation of older adults in the U.S.A. and have a greater prevalence of Alzheimer?s disease (AD) than non-Latino whites (1). Despite this, our knowledge of normal aging, cognitive decline, and AD-related neurodegeneration in Latinos is sparse. A growing body of evidence supports a link between AD onset and several modifiable factors, some of which convey risk (e.g., mid-life hypertension, sleep and mood distrurbance). Other factors are considered protective, such as engaging in regular physical activity, managing cardiovascular risk factors (i.e., diabetes, obesityand hypertension), maintaining a healthy diet, and engaging in lifelong learning (2). It is also known that some of these modifiable risk factors have a higher prevalence in Latinos, compared to non-Latinos (3). Nonetheless, how these factors independently or interactively make older Latinos more vulnerable to accumulation of AD pathology, cognitive decline, and dementia remains unclear. Thus, investigating the impact of different AD risk factors on cognition, brain function, and AD molecular markers of pathology in older Latinos is pivotal to improving prevention, early detection, and development of novel treatments and interventions for this critically underserved and understudied population. To promote recruitment and participation of Latinos in biomarker and aging research, we initiated a registry of older community-dwelling Latinos living in Massachusetts (known as the Boston Latino Aging Registry). Furthermore, with the support of an administrative supplement in 2019 we began to include more Latino participants in the ongoing NIA-funded Harvard Aging Brain Study, which is now known as Latino HABS. We propose to build upon these previous recruitment efforts to study aging and preclinical AD in non-demented older Latinos and non-Latino White individuals. All participants will undergo a comprehensive assessment of cognition, amyloid and tau PET scanning, as well as structural and resting fMRI. They will also complete self- report measures of modifiable dementia risk factors (e.g. cardiovascular disease, sleep, mood), all of which will be used to create an overall dementia risk score. Comparisons between Latinos and non-Latinos will be made in all aims with the goal of using the findings to validate and inform biomarker findings in older Latinos. Our ultimate goal is to build a cohort of older Latinos that we can be followed up overtime. For the current R01 grant, we propose to enroll a total of 200 older community dwelling individuals (60-80 years; 150 Latinos and 50 non-Latinos) and compare them to 200 already enrolled in HABS (60-80 years; 150 non-Latinos and 50 Latinos) to 1) investigate modifiable dementia risk factors and cognition in older Latinos and non-Latinos; 2) examine modifiable dementia risk factors and memory network dysfunction in older Latinos and non-Latinos; and 3) examine the associations between modifiable dementia risk factors and markers of brain pathology in older Latinos and non-Latinos.
This study proposes to use neuroimaging and cognitive measures to examine Alzheimer's disease modifiable risk factors and biomarkers in non-demented older Latinos and non-Latino Whites. This effort will greatly improve our understanding of the relationship among AD-related brain changes, modifiable risk factors and cognitive decline in Latinos. Findings from this study will also help inform the design of prevention interventions, especially those targeting risk factors and AD neurodegeneration in this understudied population.
