China National Hypertension Survey Epidemiology Follow-up Study (CHEFS)

A large prospective cohort study to examine risk factors for cardiovascular and renal disease in a representative sample of 180,000 Chinese men and women aged 40 years and older.

Investigators
Jiang He, MD, PhD, Principal Investigator
Paul K. Whelton, MD, MSc, Co-Investigator

Funding Agent
American Heart Association

Participating Institutes
Tulane University
Chinese Academy of Medical Sciences, Beijing, China

Description
Cardiovascular disease is the leading cause of death in the U.S. and most other countries. Epidemiological studies have demonstrated that high blood pressure and overweight are important modifiable risk factors for cardiovascular disease mortality. However, several studies have noted a J-shaped relationship between cardiovascular mortality and both blood pressure and body weight. Moreover, most cardiovascular risk factors have been identified from studies conducted in middle-aged men. Corresponding data for women and older persons are limited.
The China National Hypertension Survey Epidemiologic Follow-up (CHEF) study is a prospective cohort study designed to answer the two primary study questions:1). Are the associations between blood pressure (systolic and diastolic) and mortality from stroke, coronary heart disease, and all causes linear or J-shaped throughout the range of blood pressure? Are the associations consistent across different age and sex subgroups? 2). Are the associations between body mass index and mortality from stroke, coronary heart disease, and all causes linear or J-shaped throughout the entire range of body weight? Are the associations consistent across different age and sex subgroups? Secondary questions that will be addressed include: 3). Are these associations (hypotheses 1 and 2) observed in patients with a prior history of stroke or coronary disease? 4). Is cigarette smoking as well as environmental tobacco smoke associated with increased mortality from stroke, coronary disease, and all causes? Is this association consistent across different age and sex subgroups? 5). Is alcohol intake associated with increased mortality from stroke, coronary disease, and death from all causes? Is this association linear or J-shaped? Is this association consistent across different age and sex subgroups? 6). Is systolic or diastolic pressure more important in the prediction of mortality from stroke, coronary disease, and all causes?

Baseline risk factors were carefully collected during the 1991 China National Hypertension Survey. A follow-up study was conducted during 1999-2000, which included in-person interviews to ascertain disease status and vital information for all study participants and a review of hospital records and death certificates for cardiovascular and renal events. The follow-up rate was 95% over a period of 8 years.

The CHEF study will provide unique and important information for developing national prevention strategies to reduce the societal burden of cardiovascular and renal disease in China.