Inflammatory Disease Activity, Corticosteroid Use Increase Risk of Preterm Delivery

Rheumatoid arthritis (RA) and juvenile idiopathic arthritis (JIA) increase the risk of preterm delivery (PTD) in pregnant women. Additionally, treatment with corticosteroid can lead to a 2- to 5-fold increased risk of PTD in both groups, independent of disease activity. These were the results of a study conducted by researchers at the University of California San Diego.

The current prospective trial was devised to evaluate the independent effects of disease activity, medication use, and comorbid pregnancy in women who had enrolled in the study between 2004 and 2017 and who had delivered at least 1 infant. Of the 820 pregnant women (<19 weeks gestation) with inflammatory disease who were enrolled in the study in the United States and Canada, 657 had RA and 170 had JIA; 564 women without autoimmune disease were in the control group.

Participants were interviewed over the phone 2 or 3 times during pregnancy about their medication history, history of previous pregnancies, family medical history, socioeconomic and demographic characteristics, among other things. Birth outcomes in these women were obtained shortly after delivery via another telephone interview, with questions about exposure information during pregnancy, gestational age of the baby when born, mode of delivery, and any pregnancy-associated complications. Additional data was also gathered from all the healthcare providers who attended the women, before, during, and after pregnancy.

Maternal autoimmune disease was validated via medical records and medication treatment—defined as treatment at any dose for any length of time during pregnancy&mdash;was grouped by class as disease-modifying antirheumatic drugs (DMARDs), non-DMARD biologics, oral corticosteroids, nonsteroidal anti-inflammatory drugs (NSAIDs).

Study subjects were predominantly white. Women in the RA and JIA groups had a significantly higher rate of at least 3 spontaneous abortions compared with the control group and fewer women in the RA group were first-time mothers compared with the control group. Tobacco use and pregestational hypertension were more commonly reported by women with RA and JIA.

The study confirmed previous findings that active RA and JIA increased the risk of PTD compared to the control group (risk ratio [RR], 2.09; 95% CI, 1.50-2.91; and RR, 1.81; 95% CI, 1.14-2.89, respectively). Mothers with RA and JIA had a greater risk of preterm labor, early-term delivery, moderate preterm delivery, and cesarean section compared with the control group. Additionally, women with RA had a much greater risk of preterm delivery before 32 weeks of gestation while those with JIA ran a greater risk of preecalmpsia.

Diagnosis of active RA at enrollment (adjusted RR [aRR], 1.52; 95% CI, 1.06-2.18) and anytime during pregnancy (aRR, 1.52; 95% CI, 1.06-2.18) increased the likelihood of PTD. Further, medication use, specifically corticosteroids, was an additionally risk factor for PTD in these women, irrespective of their disease activity, while DMARDs or biologic medications were not.

“Further analyses are necessary to look at other categories of arthritis affecting women of childbearing age, racial disparities in these populations, and the influence of disease activity in the later stages of pregnancy on other perinatal factors that can contribute to PTD risk,” the authors conclude.

Reference

Smith CJF, Förger F, Bandoli G, Chambers CD. Factors associated with preterm delivery among women with rheumatoid arthritis and juvenile idiopathic arthritis [published online August 2018]. Arthritis Care Res (Hoboken). doi: 10.1002/acr.23730.