[1] VA Greater Los Angeles Healthcare Syst, Dept Neurol, Los Angeles, CA 90073 USA
[2] Univ So Calif, Dept Pediat, Keck Sch Med, Los Angeles, CA 90089 USA
[3] Univ Calif Los Angeles, Dept Neurol, Hlth Serv Res Program, David Geffen Sch Med, Los Angeles, CA USA
[4] Sunrise Hosp & Med Ctr, Stroke Prevent Program, Las Vegas, NV USA