1. From the Division of Cardiovascular Diseases and Internal Medicine (B.A.B., K.L., A.H., S.D., J.K., H.F., B.P.S., G.B., H.H.C., M.M.R., J.C.B., R.D.S.) and the Department of Biomedical Statistics and Informatics (K.R.B., C.G.S.), Mayo Clinic, Rochester, Minn.