Women with rheumatoid arthritis or axial spondyloarthritis who stop treatment with tumor necrosis factor inhibitors when they become pregnant may be inviting disease flares during the pregnancy, according to a report published in Arthritis Research & Therapy.
To examine the frequency of rheumatoid arthritis (RA) and axial spondyloarthritis (axSpA) flares during pregnancy, researchers prospectively followed 136 women treated at the Center for Pregnancy in Rheumatic Diseases at Inselspital Bern (Switzerland) during a 5-year period. These patients – 75 with RA and 61 with axSpA – were assessed before conception, during each trimester, and 6-8 weeks postpartum for disease activity and medication use, said Stephanie van den Brandt, MD, of the department of rheumatology, immunology, and allergology at the University of Bern, and her associates.
A total of 29% of the RA patients and 25% of the axSpA patients experienced disease flares during their pregnancies. In both groups, discontinuing TNF inhibitors at conception or early in pregnancy was one of only two factors that significantly increased the risk of flares. The other factor was elevated disease activity/C-reactive protein (CRP) levels at conception.The relative risk of a disease flare was 3.33 among RA patients and 3.08 among axSpA patients who discontinued TNF inhibitors at the time of a positive pregnancy test. In comparison, rheumatic disease remained stable throughout pregnancy in most women who were not taking TNF inhibitors before pregnancy, the investigators said (Arthritis Res Ther. 2017 Mar 20. doi: 10.1186/s13075-017-1269-1).
Most disease flares occurred in the first trimester among women with RA and in the second half of pregnancy among women with axSpA. Most women with RA who resumed taking TNF inhibitors when their disease flared responded well to the treatment, with CRP levels dropping by 70% and remission being achieved rapidly. In contrast, most women with axSpA who resumed taking TNF inhibitors did not respond as well, with CRP levels dropping by only 35%. Their disease was ameliorated but not controlled by restarting the therapy.
No sponsor was cited for this study. Dr. van den Brandt and her associates reported having no relevant financial disclosures.