Diabetes, particularly non-insulin dependent diabetes mellitus (NIDDM), and its complications have become an increasingly important health problem for many American Indian populations. Data on the progression of NIDDM risk factors from early ages are scarce. This application proposes to plan for an epidemiologic study to evaluate a number of potential risk factors for NIDDM among members of the Cherokee Nation of Oklahoma. A stratified sample of subjects will be taken across a wide range of ages and degrees of Indian blood from childhood to adulthood. Some of these risk factors are also related to cardiovascular disease, a major complication of diabetes. The study to be planned will use a pseudo-cohort design to evaluate fasting glucose and insulin, glucose tolerance, and a number of potential risk factors for NIDDM (and cardiovascular disease), such as family history of diabetes, degree of Indian blood, obesity, diet, lipids and lipoproteins, physical activity, and social and economic factors, in the Cherokees aged 5 to 40 years. The major objectives are (1) to estimate the prevalence of impaired glucose tolerance (IGT) and diabetes in Cherokees less than 40 years of age, (2) to estimate the progressive differences in these variables from childhood to adulthood, (3) to determine the relationships between the risk factors and fasting glucose and insulin, and glucose tolerance at different ages and whether the relationships vary with age, (4) to estimate the age of onset of obesity, elevated fasting glucose, glucose intolerance, insulin resistance, and deranged lipids and lipoproteins, and (5) based on the information obtained, to recommend educational programs and other timely preventive measures and, consequently, reduce the burden of diabetes and improve the health status of American Indians. During the period of the planning grant, we will expand the scope of our working relationship with members of the Cherokee Nation, their administrators, health professionals, and clinics. We also win conduct a pilot study to collect preliminary data and obtain estimates of levels of risk factors in the Cherokees in order to facilitate sample size determination and refine other procedures for the planned project. The Cherokee Nation is selected as the study population because of its high prevalence of diabetes, in degree of Indian blood, large membership, excellent health care facilities, and strong interest in research among the leaders and health professionals.