1. Department of Internal Medicine, Division of Endocrinology, Diabetes, and Metabolism, Duke University Medical Center, Durham, North Carolina.
2. Department of Internal Medicine, Durham Veterans Affairs Medical Center, Durham, North Carolina.
3. Department of Biostatistics and Bioinformatics, Duke University School of Medicine, Durham, North Carolina.
4. Department of Internal Medicine, Division of General Internal Medicine, Duke University Medical Center, Durham, North Carolina.
5. Department of Internal Medicine, Division of Infectious Diseases, Duke University Medical Center, Durham, North Carolina.