About

Rachel Whitmer Professor UC Davis Department of Public Health Sciences — Professor Rachel Whitmer
Division Chief of Epidemiology
Department of Public Health Sciences
UC Davis School of Medicine

The primary objective of our research program is to identify and understand risk and protective factors for cognitive and brain aging in populations at high risk for dementia, including ethnic minority groups and those with chronic disease such as diabetes mellitus.

Professor Rachel Whitmer is an epidemiologist with a passion for identifying modifiable risk factors for brain health and dementia in diverse populations which have previously been underrepresented in population based research. She leads a large research program funded by the National Institute of Health and the Alzheimer’s Association. Dr. Whitmer is part of the UC Davis Graduate Group Epidemiology, Graduate Group in Public Health Sciences, and is Director of the Epidemiology Core of the UC Davis Alzheimer’s Disease Center. She is a professor in the UC Davis Department of Public Health Sciences and Chief of the Division of Epidemiology. Dr. Whitmer is Principal Investigator of the Northern California site for US POINTER the first multidomain behavioral intervention clinical trial to prevent cognitive decline, funded by the Alzheimer’s Association. Dr. Whitmer is committed to mentoring junior scientists and promoting those underrepresented in research. Her mentees include Fulbright Fellows, NIH KL-2 and K99 recipients. Her H-index is 42 and her work has been published in JAMA, BMJ, Neurology, Diabetes Care, JAMA: Neurology, and Alzheimer’s Disease and Dementia.

Whitmer Lab

The Whitmer lab is a collaboration of UC Davis Department of Public Health Sciences, UC Davis Alzheimer’s Disease Center, Kaiser Permanente Division of Research, and the UCSF Department of Epidemiology and Biostatistics.

The goal of our lab is to utilize population science and epidemiology to understand why some individuals get dementia and others do not. The lab focuses on ethnoracial disparities in cognitive aging and dementia, lifecourse contributions to brain health, dementia, and Alzheimer’s disease, and metabolic and vascular influences on brain aging. We focus especially on populations that have traditionally not been included in brain aging research, including ethnic minorities and those with chronic disease. We currently have 4 NIH-funded cohort studies in the field and in early 2019 we will launch the US POINTER, a multidomain clinical trial to prevent cognitive decline.

Lifecourse Epidemiology

We have conducted significant studies on the role of midlife, modifiable risk factors for Alzheimer’s disease and dementia using the data resources of Kaiser Permanente Northern California (KPNC) as a natural laboratory for pursuing novel questions in dementia epidemiology with high clinical impact. Our work on obesity, central adiposity, smoking, total cholesterol, depression, cumulative vascular risk and diabetes were the first studies to establish that these risk factors in midlife are strongly associated with increased risk of dementia and Alzheimer’s disease. These findings, subsequently confirmed in several other data sources, contributed to a fundamental reconceptualization of dementia as a lifecourse disease with major, modifiable risk factors accumulating decades prior to diagnosis. Due to the long subclinical nature of neurodegenerative diseases, there is potential for reverse causality, and risk and protective factors operate differently, at different time points in the lifecourse, and in different populations. This overarching challenge in dementia epidemiology is a continuing, evolving, theme in our work which propels our scientific approaches.

Health Disparities

Large racial/ethnic disparities in dementia have been established, but there are very few data sources with substantial non-white participation rates. The diversity of the Kaiser Northern CA membership supports important work evaluating whether findings initially established in whites also hold true for racial/ethnic minorities. Our group published the largest and longest study of racial/ethnic differences in dementia incidence (Mayeda, ER, Glymour MM, Quesenberry CP Jr., Whitmer RA, Alzheimer's Dementia 2016 Mar). We looked at six different racial/ethnic groups and were the first to determine the incidence of dementia for Asian-Americans and Native-Americans, and the magnitude of racial/ethnic differences comprehensively. Our NIH funded epidemiological cohort studies, KHANDLE (Kaiser Healthy Aging and Diverse Life Experiences) , STAR (Study of Healthy Aging in African Americans), and LifeAfter90 examine the role of early life and lifecourse mechanisms on brain aging in multitethnic, diverse populations ( links to the tabs for these studies).

Diabetes and Brain Aging

Another major focus of our group has been on trying to understand how and why those with diabetes have accelerated brain aging and what can be done to change this. While it’s known that those with type 2 diabetes have double the risk of dementia, the driving mechanisms, underpinning pathology, and etiology behind this is not well understood. Our work is examining the timing of glycemic control and vascular complications on brain health. Individuals with type 1 diabetes are living longer than ever before and ways to help this population age successfully are not well understood. Three years ago we commenced the NIH funded SOLID (Study of Longevity in Diabetes), a cohort study of 800 elderly individuals with type 1 diabetes, and 200 with type 2 diabetes with a primary goal of delineating successful mental and physical aging in this population.