OBJECTIVE:
To assess whether the modifications to the U.S. Preventive Services Task Force (USPSTF) and American College of Obstetricians and Gynecologists (ACOG) guidelines that emphasize “lower income” status and Black racial identity (as a proxy for underlying systemic racism) as moderate risk factors for preeclampsia were associated with increased low-dose aspirin use in these groups.
METHODS:
We performed a repeated cross-sectional analysis of nulliparous patients who delivered at 24 weeks of gestation or later from 2017 to 2022 within one health care system with an indication for low-dose aspirin use during the pregnancy. Two cohorts were created, with patients matched exactly on other known risk factors for preeclampsia. The first cohort was stratified by Black and White race; the second cohort was stratified by Medicaid insurance (as a proxy for lower income) and private insurance. Two patient-level difference-in-difference analyses were performed in each matched cohort using linear regression. The pre-period included patients who delivered before 2022, and the post-period included those who delivered in 2022.
RESULTS:
The study included 31,555 participants: 11,612 in the first cohort examining race and 14,208 in the second cohort examining lower income. In the first cohort, 2,614 patients (22.5%) were matched; in the second cohort, 3,602 patients (22.6%) were matched. The rate of low-dose aspirin use among patients who self-identified as Black increased by 8.8 percentage points (95% CI, 0.076–16.9) relative to those who identified as White. The rate of low-dose aspirin use among patients with Medicaid insurance did not increase relative to those with private insurance (difference-in-difference estimate −1.1 percentage points; 95% CI, −9.3 to 7.2).
CONCLUSION:
New guidelines from the USPSTF and ACOG in 2021 that emphasized the racial inequities of preeclampsia were associated with an increase in the rate of low-dose aspirin use in Black patients but not in patients with public insurance. Despite new guidance, overall rates of low-dose aspirin use remain well below expected based on what is recommended by professional organizations.