Study Population

The MESA cohort is drawn from six regions in the U.S.:

• Forsyth County, NC
• Northern Manhattan and the Bronx, NY
• Baltimore City and Baltimore County, MD
• St. Paul, MN
• Chicago and the village of Maywood, IL
• Los Angeles County, CA

The source population for each Field Center varies in size and ethnic composition. The MESA cohort is comprised of men and women of diverse ethnic background who are 45 to 84 years old at the baseline exam and free of clinical cardiovascular disease. Each site will recruit 1,100 eligible participants, equally divided between men and women, and according to specified race/ethnicity proportions.

Before and during recruitment, the purpose, rationale, and design of the study will be publicized to residents of target areas. Successive efforts will be directed at targeted households or individuals, and will include mailings of letters and brochures, followed by personal contacts via telephone or in person. Phone calls will be the primary method of recruitment at all Field Centers.

Each Field Center has developed its recruitment procedures according to the characteristics of its community, past experience, available resources, and site-specific logistics. This protocol describes the target populations, the sampling frames, and details of recruitment methods and procedures.

Each Field Center will recruit approximately 1,100 participants from two or more of the following ethnic groups: African Americans, Asian (Chinese) Americans, Caucasians, and Hispanics. Two factors have been considered in determining Field Center-specific goals for ethnic composition:

1)  the overall ethnic profile of the MESA cohort

2)  the ethnic composition of the source population at each Field Center

In addition, it was deemed important to have overlapping ethnic groups among Field Centers in order to minimize confounding of ethnicity by site. The cohort is expected to have approximately equal number of men and women at each Field Center. The MESA age range was chosen to permit analyses of the relations between age and subclinical disease progression, and to include pre-menopausal women.