Objectives: To determine whether changes in levels of anti-cyclic citrullinated peptide (anti-CCP) and rheumatoid factor (RF) are associated with the spontaneous improvement of rheumatoid arthritis (RA) during pregnancy and with the subsequent flare postpartum.
Methods: Disease activity scores from the Pregnancy-induced Amelioration of Rheumatoid Arthritis (PARA)-study of 118 patients were available for analysis. Before conception (if applicable), at each trimester and at 6, 12 and 26 weeks postpartum levels of the autoantibodies anti-CCP, IgM-RF, IgG-RF and IgA-RF were determined. Responses in disease activity were classified according EULAR response criteria during pregnancy and postpartum, and associated with the presence or absence of autoantibodies.
Results: The median levels of anti-CCP and all subclasses of RF during pregnancy were stable, whereas postpartum the levels of anti-CCP, IgM-RF and IgA-RF declined. A significantly higher percentage of women without autoantibodies (both anti-CCP and RF negative) improved compared with women positive for either or both autoantibodies (75% vs 39%, p=0.01). The occurrence of a flare postpartum was comparable between these groups.
Conclusions: Improvement of disease activity of RA during pregnancy was not associated with changes in levels of autoantibodies during pregnancy, however, improvement may occur more frequently in the absence of anti-CCP and RF.