Search Case Control (CC)

Background

Diabetes mellitus is the third most prevalent severe chronic disease of childhood 1. Key research questions now focus on descriptive epidemiology (prevalence and incidence rates), etiology (metabolic, behavioral, genetic and immunologic risk factors), and appropriate treatment approaches. There is very limited information about the epidemiology of type 2 diabetes mellitus in youth, though it is believed that the prevalence is increasing rapidly. Risk factors similar to those in adults with type 2 are thought to be important, (e.g. obesity, positive family history), however, there are no reliable epidemiologic studies of these risk factors in youth with type 2 diabetes using appropriate controls. In addition, risk factors such as low birth weight, lack of breast-feeding, in utero exposure to maternal diabetes and less than optimal patterns of family functioning and depressive symptoms have received little epidemiologic study in populations other than American Indians. This project addresses the lack of such studies.

The SEARCH-CC is a case-control project that will study 10-22 year old children and adolescents with or without diabetes, focusing on type 2 diabetes in youth and drawing upon the CDC funded SEARCH diabetes registry project in Colorado and South Carolina.

Objectives

The SEARCH project will ascertain cases of diabetes in youth, collect immunologic, clinical, and metabolic information, and classify cases as type 1, type 2 or other types (hybrids) of diabetes. SEARCH-CC will recruit appropriate controls aged 10-22 years from three ethnic backgrounds including African Americans (AA), Hispanics (H), and non-Hispanic whites (NHW). SEARCH-CC will add selected measurements not available in SEARCH to explore or describe:

1. Specific etiologic hypotheses in the cases classified by SEARCH as type 2 diabetes.
2. Cardiovascular risk factor differences in youth with diabetes and non-diabetic controls.
3. Among controls, insulin resistance and secretion differences according to levels of the same risk factors under study.
4. Among youth with diabetes, the relationship between depression and diabetes management, quality of life, and self-concept.
5. Among youth with and without diabetes, the relationship between diabetes and depression and related psychosocial factors.

The study will:

1. Recruit non-diabetic control subjects representative of the same populations from which type 2 diabetes cases are identified in SEARCH, group matched by gender, age, and ethnic group.
2. Assess selected risk factors for type 2 diabetes, and cardiovascular disease (family history, perinatal, clinical, metabolic, behavioral, and psychosocial factors) and test specific hypotheses in case-control, and within-control designs.
3. Describe the relationship between diabetes and depression/co-morbid conditions in youth: prevalence, incidence, natural evolution of depression by type of diabetes, and impact of depression on diabetes management and complications.