[1] Univ Minnesota, Sch Med, Cardiovasc Div, 420 Delaware St SE,MMC 508, Minneapolis, MN 55455 USA
[2] LabCorp, Raleigh, NC USA
[3] Univ Minnesota, Sch Med, Dept Internal Med, Div Nephrol, 420 Delaware St SE,MMC 508, Minneapolis, MN 55455 USA
[4] Univ Pittsburgh, Grad Sch Publ Hlth, Pittsburgh, PA USA
[5] Univ Vermont, Coll Med, Dept Pathol & Lab Med & Biochem, Colchester, VT USA
[6] Univ Minnesota, Sch Publ Hlth, Div Epidemiol & Community Hlth, 420 Delaware St SE,MMC 508, Minneapolis, MN 55455 USA