African American Children, Glycemic Control, and Type 2 Diabetes (ACT)

Current literature suggests that 25-hydroxyvitamin D (25(OH)D) is inversely related to risk of type 2 diabetes mellitus (T2DM). African Americans (AA) have significantly less 25(OH)D concentrations, greater chances of poor glycemic control compared to European Americans (EA). The primary objective is to evaluate if the differences in glycemic control in children with type 2 diabetes are explained by differences in serum concentrations of 25(OH)D. A secondary aim is to demonstrate that subjects with vitamin D deficiency (serum 25(OH)D <20ng/ml) and T2DM who receive an 8 week of vitamin D treatment (50,000 IU oral vitamin D2/once per week) have greater improvement than subjects who receive placebo in glycemic control, as measured by HbA1c and endogenous insulin secretion, as assessed by area under the concentration-time curve (AUC) for mixed meal-stimulated C peptide, at 3 months after study drug administration. Research design: Randomized, placebo-controlled, double blind study design in children with T2DM and vitamin D deficiency. Glycemic control will be determined by HbA1C levels, fasting glucose and area under the curve (AUC) for glucose after a mixed meal tolerance test (MMTT). Measures of beta cell function will be determined by AUC for c-peptide and glucose after MMTT. This study is warranted in AA adolescents with T2DM as any positive interventions could have life long impact and will lead to future larger clinical trials.