Minnesota Mayo clinic retrospective, population study of RF & CCP in 1373 incident RA pts. At Dx, 37% dual seropositive, 13% +CCP only, 12% +RF only, & 38% seronegative. zDual seropositives had more erosions (31%) & flares (69% vs 51%). But +RF only highest mortality (adj 2.18) https://t.co/hPQewVgPoq