Assessment of clinically silent atherosclerotic disease and established and novel risk factors for predicting myocardial infarction and cardiac death in healthy middle-aged subjects: rationale and design of the Heinz Nixdorf RECALL Study. Risk Factors, Evaluation of Coronary Calcium and Lifestyle.

In view of consistently high cardiovascular morbidity and mortality rates, international efforts are aimed at developing tools for more precise risk prediction to allow preventive treatment targeted at high-risk individuals. Direct visualization of anatomic, preclinical atherosclerotic disease has the potential for individualized risk discrimination. Further, a variety of risk factors are actively evaluated, including markers of the activity of atherosclerotic disease, thrombogenic risk, and genetic polymorphisms. The Heinz Nixdorf RECALL (Risk Factors, Evaluation of Coronary Calcium and Lifestyle) study is a population-based, prospective cohort study of the comparative value of modern risk stratification techniques for "hard" cardiac events. It is designed and powered to define the relative risk associated with the specific extent of coronary atherosclerosis measured by means of electron-beam computed tomography (EBCT)-derived coronary calcium quantities for myocardial infarction and cardiac death in 5 years in 4200 males and females aged 45 to 75 years in an unselected urban population from the large, heavily industrialized Ruhr area. Additionally, the predictive values of conventional cardiovascular risk factors, new candidate and socioeconomic risk factors, certain genetic polymorphisms, and direct signs of subclinical disease are examined with the ankle-brachial index, resting and stress electrocardiograms, and determination of carotid artery intima-media thickness. Prospective clinical risk-benefit and health economic analyses are an inherent part of the study. Study findings with established clinical significance are reported to the participants, but the EBCT findings are withheld until the conclusion of the study. The Heinz Nixdorf RECALL study will define appropriate methods for identifying high-risk subgroups in the general urban population who may derive the greatest benefit from preventive treatment.