1Section of Nephrology, Selzman Institute for Kidney Health, Baylor College of Medicine, Houston, Texas 2Section of Nephrology, Michael E. DeBakey Veterans Affairs Medical Center, Houston, Texas 3Michael E. DeBakey VA Medical Center Health Services Research & Development Center for Innovations in Quality, Effectiveness and Safety, Houston, Texas 4Institute of Clinical and Translational Research, Baylor College of Medicine, Houston, Texas Correspondence: Dr. William E. Mitch, Section of Nephrology, Baylor College of Medicine, One Baylor Plaza, 100.37S, Houston, TX 77030. Email: [email protected] Published online ahead of print. Publication date available at www.jasn.org. See related article, "Muscle Mass and Serum Creatinine Concentration by Race and Ethnicity among Hemodialysis Patients," on pages 66–73.