The Northwestern University serves as one of six Field Centers for the Multi-Ethnic Study of Atherosclerosis (MESA), a study of the correlates, predictors and progression of subclinical cardiovascular disease (CVD) (disease detected non-invasively before it has produced clinical signs and symptoms) in a diverse population-based sample of men and women aged 45-84 who had no evidence of clinical CVD at baseline. Six thousand eight hundred and fourteen (6,814) participants were recruited from six Field Centers during 2000-2002 and examined for evidence of subclinical coronary atherosclerosis, using computed tomography, cardiac MRI, carotid ultrasound, flow-mediated brachial artery dilation, radial artery tomometry, ankle-brachial index measurement, and retinal photography and, in subsets, abdominal aortic CT, carotid MRI, cardiac MRI tagging for measures of regional myocardial function;established and putative laboratory risk markers;socioeconomic, psychological, behavioral, nutritional and environmental characteristics;and genetic factors. Selected components were repeated over three subsequent examinations through 2007. The cohort has been followed for clinical events since baseline to ascertain and characterize new clinical events and other changes in health status, including changes in medications. The four scientific objectives for the period 2008 through 2015 are (1) identify factors related to progression of subclinical to clinical CVD;(2) identify predictors of decline in ventricular function;(3) further understanding of the basis for racial/ethnic difference in CVD;and (4) provide a platform for in-depth ancillary studies of CVD and other areas. All surviving and willing members of the MESA cohort will be followed up during the time period and included in an fifth examination during 2010-2012. The study will support in-depth ancillary studies that are funded outside of the current contracts. These studies will be operationally integrated into the main study, and the data will be shared across both types of studies, per current MESA and NIH data-sharing policies. The study's data will be provided to interested investigators through a defined process that encourages maximum data utilization but that protects participant confidentially. The study will also serve as a training ground for junior investigators, who will work with senior investigators and be provided with access to the MESA data set and guidance on conducting research. The MESA-EYE component (refraction and fundus photography) was integrated into the second MESA visit in which 6235 people participated between September 2002 and December 2003.
The aims of the ocular component were to document the presence and severity of retinal microvascular changes (as interpreted from digital retinal photos) indicative of macular degeneration and diabetic retinopathy, as well as to describe their interrelationships with cross-sectional and longitudinal measures of microvascular and macrovascular systemic disease as defined clinically, by imaging modality, or by analysis of biological laboratory measures. The visual acuity/objective refraction component was designed to allow us to estimate visual impairment by sex and ethnicity, determine the degree to which visual impairment could be reduced with better refractive correction, and correlate visual findings with retinal pathology. Analyses of various ocular phenotypes, including retinal microvascular disease in MESA Family's ancillary study.