Disease activity for women with psoriatic arthritis seeking pregnancy was relatively stable through 1 year after delivery, but there was a significant jump at 6 months postpartum follow-up, based on data from a prospective study of more than 100 patients.
Previous research has described rheumatoid arthritis remission during pregnancy, but the symptoms of psoriatic arthritis (PsA) before, during, and after pregnancy have not been well studied, wrote Kristin Ursin, MD, of Trondheim (Norway) University Hospital, and her colleagues.
In a study published in Arthritis Care & Research, the investigators reviewed data from 108 pregnancies in 103 women with PsA who were diagnosed between January 2006 and October 2017.
The participants were enrolled in a Norwegian nationwide registry that followed women with inflammatory diseases from preconception through 1 year after delivery. Disease activity was measured using the DAS28-CRP (28-Joint Disease Activity Score with C-reactive Protein). Participants were assessed at seven time points: before pregnancy, during each trimester, and at 6 weeks, 6 months, and 12 months after delivery.
Although approximately 75% of the women had stable disease activity throughout the study period, activity spiked at 6 months after delivery; DAS28-CRP scores at 6 months post partum were significantly higher than scores at 6 weeks post partum (2.71 vs. 2.45, respectively; P = .016).
The researchers conducted an additional analysis of the potential role of tumor necrosis factor inhibitor use and found that women taking a TNFi had significantly lower disease activity during pregnancy, compared with women not taking a TNFi; mean DAS28-CRP scores at 6 months post partum for these groups were 2.22 and 2.72, respectively (P = .043).
The study was limited by the use of DAS28-CRP as the main measure of disease activity; the index does not include potentially affected distal interphalangeal joints. In addition, not all the participants were assessed at each of the seven time points. However, the results suggest that most pregnant women with PsA experience low levels of disease activity, the researchers said. “Future research on pregnancy in women with PsA should include extended joint count (66/68 joints), and assessment of dactylitis, entheses, axial skeleton, and psoriasis,” they added.
The researchers had no financial conflicts to disclose. The study was funded by the department of rheumatology at Trondheim University Hospital and the Research Fund of the Norwegian organization for people with rheumatic disease.
SOURCE: Ursin K et al. Arthritis Care Res. 2018 Sep 7. doi: 10.1002/acr.23747.