Increased Risk of Preterm Delivery Subtypes and Hypertensive Disorders of Pregnancy in First Deliveries of Patients With Systemic Vasculitis.

Abstract

The goal of this study was to investigate the risk of preterm birth subtypes and hypertensive disorders of pregnancy in patients with systemic vasculitis using large, statewide databases. Births to nulliparous patients with prevalent systemic vasculitides (Takayasu arteritis [TAK], Behçet disease [BD], antineutrophil cytoplasmic antibody-associated vasculitis [AAV], and Kawasaki disease [KD]) were identified using International Classification of Diseases, Ninth Revision codes in linked administrative data and birth records from the California Department of Health Care Access and Information and California Vital Statistics from 1991 to 2012. Hypertensive disorders of pregnancy and preterm delivery (PTD) subtypes were identified. Multivariable-adjusted Poisson models estimated risk ratios (RRs) of these outcomes compared with the general birthing population without history of rheumatic disease. A total of 96 births to nulliparous patients with systemic vasculitis were identified (TAK, 14; AAV, 31; BD, 26; KD, 15) and compared with 4,191,900 births of the nulliparous general population. Adjusted RRs for all PTD types were elevated in patients with vasculitis (RR 3.21, 95% confidence interval [CI] 2.15-4.79), as were the RRs of all PTD subtypes including preterm premature rupture of membranes (RR 4.30, 95% CI 2.05-9.01) and spontaneous PTD (RR 4.99, 95% CI 3.01-8.28). Of the spontaneous PTDs among patients with vasculitis, 16.7% were early PTDs (20-31 weeks), with the remaining 83.3% occurring between 32 to 36 weeks. Patients with vasculitis also had an elevated risk of hypertensive disorders of pregnancy (RR 2.96, 95% CI 1.72-5.10). Among first-time births, we found that patients with systemic vasculitis have an elevated risk of PTD subtypes as well as hypertensive disorders of pregnancy.