Low-Dose Aspirin for the Prevention of Preeclampsia

Factors Associated with Guideline Concordant Clinician Counseling about Low-Dose Aspirin to Prevent Preeclampsia in Nulliparous Patients

OBJECTIVE

The primary aim of this study was to examine the United States Preventative Services Task Force (USPSTF) guidelines concordant low-dose aspirin (LDA) counseling and factors associated with counseling in nulliparous birthing individuals.

STUDY DESIGN

We conducted a retrospective cohort study of nulliparous birthing individuals who delivered between January 1, 2019 and June 30, 2020 and received prenatal care at the Duke High Risk Obstetrical Clinics (HROB). All nulliparous patients over 18 years old who established or transferred care to HROB by 16 weeks, 6 days were included in the analysis. We excluded patients with more than two previous first-trimester pregnancy losses, multiple gestation, a known contraindication to LDA, initiation of LDA prior to their prenatal care, or documented medical history of coagulation disorder. Bivariate associations between demographic/medical characteristics and our primary outcome, receipt of counseling (yes/no), were assessed using two-sample t-tests for continuous variables and chi-square or Fisher's exact test for categorical variables. Factors significantly associated with the primary outcome (p < 0.05) were entered into the multivariable logistic regression model.

RESULTS

Among 391 birthing individuals included in the final analysis cohort, 51.7% of eligible patients received guideline consistent LDA counseling. Factors associated with increased odds of LDA counseling were advanced maternal age (adjusted odds ratio [aOR]: 1.05, 95% confidence interval [CI]: 1.01-1.09), Black race compared with White race (aOR:1.75, 95% CI: 1.03-2.98), chronic hypertension (aOR: 4.17, 95% CI: 1.82-9.55), and obesity (aOR: 5.02, 95% CI: 3.12-8.08).

CONCLUSION

Approximately half of all nulliparous birthing individuals had appropriately documented LDA counseling. The USPSTF guidelines on LDA for preeclampsia risk reduction are complex, which may lead to ineffective provider adherence. Efforts to simplify guidelines and improve LDA counseling are vital to ensuring this low-cost, evidence-based preeclampsia prevention is used in a consistent and equitable manner.

KEY POINTS

· A total of 51.7% of eligible patients received guideline consistent LDA counseling.. · Advanced maternal age , body mass index > 30, Black race, and chronic hypertension associated with increased odds of counseling.. · Among patients most likely to be counseled, high numbers did not receive LDA counseling..

Molecular Targets of Aspirin and Prevention of Preeclampsia and Their Potential Association with Circulating Extracellular Vesicles during Pregnancy

Uncomplicated healthy pregnancy is the outcome of successful fertilization, implantation of embryos, trophoblast development and adequate placentation. Any deviation in these cascades of events may lead to complicated pregnancies such as preeclampsia (PE). The current incidence of PE is 2–8% in all pregnancies worldwide, leading to high maternal as well as perinatal mortality and morbidity rates. A number of randomized controlled clinical trials observed the association between low dose aspirin (LDA) treatment in early gestational age and significant reduction of early onset of PE in high-risk pregnant women. However, a substantial knowledge gap exists in identifying the particular mechanism of action of aspirin on placental function. It is already established that the placental-derived exosomes (PdE) are present in the maternal circulation from 6 weeks of gestation, and exosomes contain bioactive molecules such as proteins, lipids and RNA that are a “fingerprint” of their originating cells. Interestingly, levels of exosomes are higher in PE compared to normal pregnancies, and changes in the level of PdE during the first trimester may be used to classify women at risk for developing PE. The aim of this review is to discuss the mechanisms of action of LDA on placental and maternal physiological systems including the role of PdE in these phenomena. This review article will contribute to the in-depth understanding of LDA-induced PE prevention.