1. From the Division of Cardiology (R.D.), University of Pennsylvania, Philadelphia; the Division of Cardiology (N.S.), University of Washington, Seattle; Collaborative Health Studies Coordinating Center (R.K.), University of Washington, Seattle; the Division of Nephrology (M.J.S.), Tufts Medical Center, Boston, Mass; The Renal-Electrolyte Division (L.F.F.), University of Pittsburgh School of Medicine, and the Renal Section, VA Pittsburgh Healthcare System, Pittsburgh, Pa; the Division of Renal...