[1] IMSS, Hosp Especialidades, Ctr Med La Raza, Div Res, Mexico City 02990, DF, Mexico
[2] IMSS, Hosp Especialidades, Ctr Med La Raza, Clin Epidemiol Res Unit, Mexico City 02990, DF, Mexico
[3] IMSS, Hosp Especialidades, Ctr Med La Raza, Dept Internal Med, Mexico City 02990, DF, Mexico
[4] Univ Nacl Autonoma Mexico, Mexico City 04510, DF, Mexico