[1] Feinberg Sch Med, Dept Prevent Med, Chicago, IL USA
[2] Univ N Carolina, Dept Nutr, Chapel Hill, NC USA
[3] Univ N Carolina, Dept Epidemiol, Chapel Hill, NC USA
[4] Univ Calif San Francisco, Dept Vet Affairs Med Ctr, San Francisco, CA 94143 USA
[5] Univ Calif San Francisco, Dept Med, San Francisco, CA 94143 USA
[6] Univ Calif San Francisco, Dept Epidemiol & Biostat, San Francisco, CA 94143 USA