Abstract
Objective This study examined maternal cardiovascular events relative to adverse pregnancy outcomes among individuals with autoimmune rheumatic diseases (ARDs), primary antiphospholipid syndrome (APS), and those with neither.
Methods Utilizing a California population-based birth cohort (2005-2020), we identified cardiovascular events, ARDs, and APS through ICD codes in maternal discharge records. Selected adverse pregnancy outcomes identified from birth certificates were preterm birth (PTB: <37 weeks' gestation), small-for-gestational-age infants (SGA, birth weight <10th centile for age and sex), and a composite of either outcome. Adjusted risk ratios (aRRs) for adverse outcomes and their 95% confidence intervals (CIs) were calculated.
Results Cardiovascular events occurred more frequently in individuals with ARDs (265/19,340, 1.4%) and primary APS (428/7,758, 5.5%) than those without (17,130/7,004,334, 0.3%). The presence versus absence of cardiovascular events was associated with a greater incidence of adverse outcomes in ARD (53.2% versus 26.6%), APS (30.6% versus 20.7%), and non-ARD/APS pregnancies (28.2% versus 15.2%). Cardiovascular events were associated with increased risks of SGA in all groups (aRRs 1.2-1.5), and with PTB in ARD (aRR 1.6, 95% CI 1.3-2.0) and non-ARD/APS (aRR 1.7, 95% CI 1.7-1.8) pregnancies.
Conclusion Cardiovascular events were associated with modestly increased risks (20-70%) for PTB, SGA, or both across groups. Notably, >50% of ARD pregnancies with cardiovascular events experienced adverse pregnancy outcomes. Given that ARD and APS pregnancies have higher (although still low) rates of cardiovascular events and have higher baseline risks of adverse pregnancy outcomes than the general population, the additional burden conferred by cardiovascular events is clinically important.
