Conditions: Pre-diabetes
Keywords: pre-diabetes minorities oral glucose tolerance test disposition index insulin secretion insulin sensitivity diabetes
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 117
Healthy volunteers: no

Brief summary:
Vitamin D supplementation in minority subjects with both pre-diabetes and low vitamin D levels will delay the development of diabetes.

Detailed description:
Low vitamin D levels 1) are associated with abnormalities in insulin secretion and insulin action, 2) predict the development of diabetes in those without diabetes, and 3) are more common in people with diabetes. Minority populations (African-Americans and Latinos) are more likely to have both low levels of vitamin D and diabetes. This study will identify minority individuals who are at increased risk for diabetes (those with central obesity, family history of diabetes in first degree relatives and either with hypertension or being treated for hypertension), and determine if they have both pre-diabetes, ie, impaired fasting glucose and/or impaired glucose tolerance, and low levels of vitamin D. Those that have both will be randomized to either high doses of vitamin D or placebo and insulin secretion and action as well as changes in the oral glucose tolerance test (reversion to normal, maintenance of pre-diabetes or development of diabetes) will be monitored at 3 month intervals for one year. This study will test the hypothesis that the increased amount of diabetes in minority populations may be due in part to low levels of vitamin D and whether supplementing this vitamin may delay the development of diabetes.

Arms:
arm 1: Subjects with low vitamin D levels and pre-diabetes arm 2: Subjects with low vitamin D levels and pre-diabetes

Interventions: intervention 1: vitamin D intervention 2: placebo
Intervention descriptions: intervention 1: liquid vitamin D3 dissolved in medium chain triglyceride once a week intervention 2: medium chain triglyceride given once per week

Protocol document: