Pilot 4
Yan Sun, PhD
Department of Epidemiology
School of Public Health
University of Michigan
Email: yansun@umich.edu
Dr. Sun’s web page
Yan Sun is an Assistant Reseach Scientist in the department of Epidemiology. His research interests are identifying genetic factors, environmental factors and their interactions to develop statistical and computational tools to understand cardiovascular disease and other chronic diseases; Managing high throughput biomedical data including genomic information and genetic variation data in genomic epidemiology studies; building data mining platforms for genetic and statistical analysis for public health research; developing predictive models to determine high risk population to provide personal preventative health care and medication; and understanding the risks of cardiovascular disease and hypertension in minority groups such as African American and Chinese.
ABSTRACT
A comparative study of the prevalence and predictors of hypertension in Chinese living in China vs. living in the US
(Y. Sun PI)
(1-year pilot)
Hypertension is a major risk factor for atherosclerosis and target-organ damage of the heart, brain and kidneys. Nearly 65 million individuals in the United States have hypertension and health care costs attributable to hypertension and its associated target-organ damage exceed $400 billion per year. The prevalence of hypertension is higher in African-Americans than in Whites, but the hypertension prevalence and risks have not been well documented in other minority groups such as Chinese. In addition, there may be important heterogeneity within Chinese depending on their place of residence. For example past work has shown that coronary heart disease prevalence is higher among Japanese living in US than it among Japanese living in Japan, and the stroke prevalence has opposite direction. Therefore, a comparative study of the hypertension prevalence of Chinese living in both US and China is important to understand the environmental risk factors of hypertension and to evaluate their effects.
In this application, we propose to use data from a sample of Chinese living in the US and Chinese living in China to investigate differences in hypertension prevalence and in the predictors of hypertension prevalence among Chinese living in the US and in China. In addition, because preliminary analyses suggest that gender differences in hypertension are present in China but not in Chinese living in the US we will also investigate predictors of gender differences. To understand the inequity of the hypertension prevalence, we will investigate a range of environmental risk factors, including social (income, education), behavioral (smoking, drinking, diet, physical activity) and demographic (age, sex, body mass index) factors with known and unknown biological mechanisms relating to hypertension. The identification of the risk factors associated with the inequity of hypertension will help understand, prevent, treat and control hypertension in Chinese. More generally, this proposal fits within the general theme of Michigan Center for Integrative Approaches to Health Disparity (CIAHD) which is to investigate the presence and sources of heterogeneity in cardiovascular risks within race/ethnic groups.
The following specific aims will be accomplished:
Aim 1. To investigate differences in the prevalence and predictors of hypertension between US Chinese and Chinese living in China. This aim will be accomplished by comparing data from MESA to a CDC survey conducted in Tianjin, China. To identify the risk factors of hypertension in Chinese ethnicity, we will test for the effects associated with hypertension, as well as systolic and diastolic blood pressure (BP) measurements in Tianjin and MESA Chinese separately. We will compare and validate the associations across the two studied populations using the same statistical model.
Aim 2. To examine sex differences in US Chinese and Chinese living in China and to investigate the risk factors contributing to any observed sex differences. In order to do this we will firstly evaluate the sex effect in both MESA and Tianjin Chinese samples using the results from Aim1. We will explore the cause of the sex differences if it is present by a) investigating the extent to which differences in the distribution of risk factors is associated with sex difference in hypertension and BP measurements; and b) examining whether the risk factors have different effects in men and in women.