Improved pregnancy outcomes in systemic lupus erythematosus: A retrospective study of pregnancies from a single centre in Denmark from 2010–2020 compared with the period 1990–2010

Abstract

Objectives Over the past decades new international guidelines recommend that pregnant Systemic lupus erythematosus (SLE) patients are monitored closely in a multi-professional team throughout pregnancy. The importance of low disease activity before pregnancy and continued treatment during pregnancy has been established. However, there is still a high risk of adverse pregnancy outcome (APO). The APO in a Danish SLE cohort was evaluated and compared with the results in a previous study cohort from the same centre and referral area. Methods This retrospective cohort study used the local patient registry to identify pregnancies in SLE patients followed at the Department of Rheumatology, Aarhus University Hospital, Denmark, from January 2010 to October 2020. In total, 66 pregnancies were registered in 41 women. Data were compared with a previous retrospective study (1990–2010) from the same hospital. Results Adverse pregnancy outcome occurred in 65% of pregnancies. Forty-seven pregnancies resulted in a live birth, while 15 ended in miscarriages. Compared to the 1990–2010 cohort, a numerical reduction in preterm deliveries (7.58% vs. 17.9%) and emergent caesarean (6.1% vs. 15.5%) was observed, although not reaching statistical significance ( p = .07 in both cases). Further, a higher average birth weight (3045 g vs. 2870 g) as well as a higher number of pregnancies and live births per year were observed. Gestational hypertension was significantly reduced from 23.8% to 13.6% ( p = .05). Significantly more patients were treated with prednisolone (66.7% vs 35.7%, p = .0002), hydroxychloroquine (6% vs. 73.4%, p < .0001) and acetylsalicylic acid (39.3% vs. 73.1%, p = .0001) in 2010–2020 compared to the 1990–2010. Conclusion We observed significant improvements in the frequency of some APOs in the recent 2010–2020 cohort compared with the previous cohort followed from 1990 to 2010. However, even though a specialized multi-professional team closely follows SLE patients through their pregnancies, pregnancy in SLE still carries a high risk of APO.

Identifying pregnancy episodes and estimating the last menstrual period using an administrative database in Korea: an application to patients with systemic lupus erythematosus

“…We also observed a higher prevalence of spontaneous abortion (28%) among patients with SLE compared to the previously reported range (5-22%). 21,[27][28][29][30] A prior study, which used nationwide claims databases in Korea, reported a spontaneous abortion prevalence of 22% but utilized more restricted definition (O02O06) compared to definition used in our study (O01O08). 21 Applying the same definition led to a slightly lower estimated prevalence of spontaneous abortion at 26% (Table S8).…”

“…A key strength of our study is large dataset of pregnant women with SLE, which is particularly valuable due to the rarity of this population. In contrast to previously studies with 100-200 SLE pregnancy cases, our study benefits from increased statistical power [ 26 , 27 , 29 , 31 , 32 ]. Our pregnancy algorithm refined previous outcome-specific methods; however, it is important to emphasize that this algorithm is not a validation study using a database linked with electronic medical records or pregnancy registry.…”

“…23 In our study, the prevalence of preterm birth among patients with SLE was found to be 11%, which is lower than the range reported in institutional studies (13%40%). [26][27][28][29][30]32 The underuse of preterm and sonography codes was observed before 2016 in the NHID, reflecting the expansion of reimbursement policy coverage in 2016 for preterm infant care and prenatal sonography. 24,25 Furthermore, preterm delivery diagnoses with a specified GA window were implemented in the Korean administrative claims database in 2016 (Table S7).…”

“…The prevalence of pregnancy outcomes among patients with SLE, as determined by our algorithm, was compared with that reported in cohort studies, primarily utilizing institutional data, to assess external validity. 21,[26][27][28][29][30][31] E p u b a h e a d o f p r i n t…”

“…In contrast to previously studies with 100-200 SLE pregnancy cases, our study benefits from increased statistical power. 26,27,29,31,32 In this study, we developed an advanced algorithm for determining pregnancy outcomes and estimating the LMP using an administrative claims database in Korea. The algorithm incorporates a hierarchical approach to mitigate miscoding or cross-coding, a clinically plausible gap for subsequent LMP and outcomes, and diagnoses and procedures with the trimester or GA. Further validation studies, including comparison with pregnancy registries or electronic health records, are needed.…”