(323) Use of healthcare administrative claims data in observational studies of antirheumatic drug effects on pregnancy outcomes: a scoping review

Background: Pregnancies in individuals with rheumatic conditions warrant close monitoring due to an increased risk for adverse outcomes. There have been significant therapeutic advances in antirheumatic drug therapies over the past few decades. However, most therapies are not well studied for use in pregnant individuals, who are typically excluded from drug trials due to unknown potential risks to both mother and fetus.

Objectives: To describe how antirheumatic drugs and associated adverse pregnancy outcomes have been investigated in observational studies that use healthcare administrative claims data.

Methods: We conducted a scoping review of MEDLINE, Embase, CINAHL and grey literature to identify observational studies that have used claims data to investigate the perinatal use and effects of antirheumatic drugs in pregnant individuals with prevalent rheumatic conditions (rheumatoid arthritis, systemic lupus erythematosus, psoriatic arthritis, and ankylosing spondylitis). Search terms combined four main concepts: rheumatic diseases, drug therapy, pregnancy, and claims data. Clinical trials, case studies, opinion pieces, and abstracts were excluded. Articles were screened and extracted by two independent reviewers. Data were reported descriptively.

Results: A total of 3,737 studies were identified by the search strategy, with 30 studies eligible for inclusion. Claims data were used in 18 (60.0%) studies, while 12 (40.0%) used registry data alone. Most studies (n = 21, 70.0%) examined the effects of both conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) and biological DMARDs (bDMARDs). In total, 30 unique adverse pregnancy outcomes were reported in claims studies (n = 18, 60.0%), with preterm birth (n = 10, 55.6%), congenital anomalies (n = 8, 44.4%), stillbirth (n = 7, 38.9%), preeclampsia (n = 6, 33.3%), and caesarean delivery (n = 6, 33.3%) being the most commonly reported. Notably, the definitions used to identify these conditions were either highly variable or not reported across studies. ICD codes used to identify congenital anomalies were specified in 6 (33.3%) studies, more than for any other pregnancy outcome. Claims definitions were specified for all 6 (33.3%) of these studies, only 5 (27.8%) of which were also validated.

Conclusions: We found substantial ambiguity and variability in terms of how adverse pregnancy outcomes were defined in claims data. There is a need for greater transparency and consistency in outcome reporting in observational studies leveraging claims data.