1. San Francisco Coordinating Center, California Pacific Medical Center Research Institute , San Francisco, CA , USA
2. Division of Endocrinology , Department of Internal Medicine, , Yongin , South Korea
3. Yongin Severance Hospital, Yonsei University College of Medicine , Department of Internal Medicine, , Yongin , South Korea
4. Department of Epidemiology and Biostatistics, University of California , San Francisco, San Francisco, CA , USA