The first phase of the study had a cross-sectional design. In this phase, echocardiography was used to measure left ventricular dimensions, mass, volume and function and fundoscopic examination and fluorescein angiography were used to determine retinal vascular abnormalities. Data were collected on the independent variables of age, sex, race, obesity, level and duration of increased blood pressure, ambulatory variability of blood pressure, family history of hypertension, treatment with antihypertensive medication, sodium intake, smoking, alcohol use, fasting blood glucose, hemoglobin, basal plasma renin activity, plasma catecholamines, cardiovascular reactions to mental stress and to exercise. Multiple regression analysis was used to determine which of the independent variables were independently associated with left ventricular mass, creatinine clearance, and retinal vascular abnormality.