[1] Vet Affairs Med Ctr, Massachusetts Vet Epidemiol Res & Informat Ctr, W Roxbury, MA 02132 USA
[2] Brigham & Womens Hosp, Dept Med, Div Prevent Med & Cardiovasc Dis, Boston, MA 02115 USA
[3] Harvard Univ, Sch Med, Dept Ambulatory Care & Prevent, Boston, MA USA
[4] Harvard Univ, Sch Publ Hlth, Dept Epidemiol, Boston, MA 02115 USA