An elevated sFlt-1/PlGF-ratio has been validated as a significant predictor of preeclampsia, but has not been established in women with rheumatoid arthritis (RA). We explored whether the sFlt-1/PlGF-ratio could be altered due to disease activity in RA, and could be applied in this population to predict preeclampsia. Since sulfasalazine has been suggested to improve the angiogenic imbalance in preeclampsia, we also aimed to examine whether sulfasalazine could affect sFlt-1 or PlGF levels.Making use of a nationwide, observational, prospective cohort study on pregnant women with RA, sFlt-1 and PlGF were measured in the third trimester. A total of 221 women, aged 21-42 years, were included, with a median gestational age of 30 + 3 weeks.No differences in sFlt-1 or PlGF were observed between women with high, intermediate or low disease activity (p= 0.07 and p= 0.41), whereas sFlt-1 and PlGF did not correlate with DAS28-CRP score (r=-0.01 and r=-0.05, respectively). Four (2%) women with a sFlt-1/PlGF-ratio ≤38 developed preeclampsia in comparison to three (43%) women with a ratio > 38, corresponding to a negative predictive value of 98.1%. Sulfasalazine users (n = 57) did not show altered levels of sFlt-1 or PlGF in comparison to non-sulfasalazine users (n = 164, p= 0.91 and p= 0.11).Our study shows that in pregnant women with RA, the sFlt-1/PlGF-ratio is not altered due to disease activity and a cut-off ≤38 can be used to exclude preeclampsia. Additionally, sulfasalazine use did not affect sFlt-1 or PlGF levels in this population.
Rugina I Neuman, Hieronymus T W Smeele, A H Jan Danser, Radboud J E M Dolhain, Willy Visser