Northwestern University Feinberg School of Medicine

Department of Preventive Medicine

Kershaw Lab

Social Environment and Health Lab 

Our group focuses on understanding the contributions of the social environment to cardiovascular health and health disparities over the life course. We have used various existing datasets to evaluate different aspects of the social environment including chronic stress, social relationships, and racial/ethnic residential segregation. Our work to date has largely centered on cardiovascular disease risk factors and outcomes, but we are expanding into adverse pregnancy outcomes as well.  

Current Research Projects

Chicago Healthy Eating Environments and Resources (CHEER) Study

Improving neighborhood access to healthy foods is a priority for public health departments across the country as part of an effort to give communities the resources needed to make positive changes in their eating behaviors that improve their overall health and lower obesity. However, recent research suggests improving healthy food availability alone may not be sufficient to improve eating behaviors or reduce obesity risk. Further work is needed to understand how individual-environment interactions influence eating decisions. To meet this need, we developed the Chicago Healthy Eating Environments and Resources (CHEER) study. Starting this fall, we will collect information about eating behaviors and food availability in diverse neighborhoods in Chicago to better understand how women aged 18-44 years use their environment, available resources, and each other to make eating decisions that influence overall health, obesity, and related conditions. Our study is important because a better understanding of how people interact with their environments and how these interactions influence health will help guide the development of more effective policies and interventions to promote healthful behavior change.

Lifecourse Social Adversity, DNA Methylation, and Cardiovascular Disease Risk

Epigenetic modifications such as DNA methylation may represent an important modifiable molecular mechanism through which social adversity early in life contributes to CVD disparities in adulthood. DNA methylation markers may also provide insight into whether modifications due to early life exposures are permanent. However, although DNA methylation is believed to be a dynamic process influenced by changes in the environment, few studies have empirically evaluated the plasticity of methylomic markers to changes in patterns of social adversity over the life course. Furthermore, while studies have hypothesized that these epigenetic modifications increase CVD risk, previous research has not empirically tested whether associations of lifecourse social adversity with CVD risk markers are mediated by methylomic markers. This is an important mechanistic gap in the literature because it limits our understanding of the role DNA methylation plays in social CVD disparities. In response to these critical gaps in the literature, the overall objective of this study is to determine associations of patterns of social adversity over the life course to DNA methylation and cardiometabolic health. We will achieve our objective using 25 years of longitudinal data on 1,200 black and white participants of the Coronary Artery Risk Development in Young Adults (CARDIA) study (18-30 years old at baseline) with gene expression profiling data and whole blood methylation profiling data available at two time points. Specifically, we aim to use epigenome-wide methylation profiling data to identify methylomic markers of social adversity and to test whether associations of lifecourse social adversity with cardiometabolic health are mediated by adversity-associated methylomic markers. A better understanding of the extent to which early life exposures are modifiable is necessary to guide the content and timing of interventions to address social disparities in CVD.

Racial Residential Segregation and Adverse Pregnancy Outcomes

Black-white disparities in adverse birth outcomes are large and persistent in the U.S. In 1975, black infants were 2.1 times more likely than white infants to be low birthweight (<2500 g), and over 30 years later black infants are still 1.8 times more likely to be low birthweight. Decades of research in this area have led to the identification of several inter-related biological, psychological, social, and environmental explanations for these disparities. Several studies suggest the overlapping factors that put black women at greater risk of adverse birth outcomes may be related to racial residential segregation, the systematic separation of groups into different neighborhoods by race. However, studies to date have relied on birth certificate data, and while research suggests most maternal demographic data and basic infant characteristics like birthweight are accurately reported, obstetric procedures and maternal and infant medical conditions have been consistently underreported. The use of electronic health records will allow us to better evaluate the physiologic pathways linking segregation to low birthweight among infants born to black mothers. Thus, the overall objective of this project is to use the EDW to examine whether racial and economic residential segregation are independently associated with low birthweight and related adverse pregnancy outcomes. Findings from this study will provide valuable data that will help guide the development of environmental policies and multi-level interventions to facilitate the adoption of healthier behaviors and the promotion of more comprehensive prenatal care to better prevent these outcomes.

Longitudinal Associations of Neighborhood-Level Racial Residential Segregation and Cardiometabolic Health

Although a growing number of studies have investigated the contributions of the residential environment, few have examined the possible role of neighborhood-level racial residential segregation and these studies have largely been cross-sectional. Thus, the purpose of this study is to use geocoded information on Coronary Artery Risk Development in Young Adults (CARDIA) study participants to assess longitudinal associations of a spatial, contextual measure of neighborhood-level racial residential segregation with several cardiometabolic health indicators. Specifically, this study aims to 1) examine longitudinal associations of neighborhood-level residential segregation with body mass index, waist circumference, diabetes, blood pressure, diet, and physical activity; 2) test whether these associations are mediated by chronic stress and measures of the built environment; and 3) assess whether these associations are modified by gender, race, and neighborhood poverty. Marginal structural modeling will be used to account for time-varying confounding in order to more closely approximate the causal effect of neighborhood-level residential segregation on several cardiometabolic health outcomes. A better understanding of how the process of segregation influences health can help guide the development of more effective interventions to reduce disparities in cardiometabolic health.

Education/Training Opportunities

If you are interested in joining the lab or working on a specific project related to residential segregation or other aspects of the social environment, please contact Dr. Kershaw.

Publications

To view a listing of publications, please visit her profile on PubMed

Principal Investigator

KK

Kiarri N Kershaw

Assistant Professor of Preventive Medicine

Contact Us

If you are interested in learning more about our research, opportunities for collaborating or training opportunities, please contact Dr. Kershaw at k-kershaw@northwestern.edu.