(535) Racial Disparities in Severe Maternal Morbidity: Identifying Predictors for Designing Interventions and Risk Reduction

Objective: To evaluate differences in severe maternal morbidity (SMM) and identify key predictors of SMM among Non-Hispanic Black (NHB) versus Non-Hispanic White (NHW) pregnancies

Study Design: We undertook a retrospective cohort study of all patients receiving prenatal care and delivering at a single academic tertiary medical center from 2017 – 2013. The cohort was divided based on self-identified race into 2 subgroups - i.e. NHB vs NHW. Our primary outcome was SMM as defined by the Centers for Disease Control (CDC). Demographic and clinical characteristics were abstracted from electronic records and compared across study groups using Student’s T test and chi2/Fischer’s exact test for continuous and categorical data, respectively. The Kruskal Wallis test was used to compare nonparametric data. Multivariable regression analyses were used to identify the key predictors of SMM in each cohort.

Results: Of the 6403 patients, 4200 (66%) identified as NHB, while 2203 (34%) identified as NHW. NHB patients were significantly younger (p< .01), had governmental insurance (p< .01) with a higher BMI (p< .01), and presented at later gestational age at prenatal care initiation (p< .01). Overall, 417/6403 (7%) of the cohort had a SMM event with a higher incidence of SMM among NHB patients as compared to their NHW counterparts [307/4200 (7%) vs 110/2203 (5%), p< .05]. Rates of individual SMM events were similar across both groups except for higher rates of sickle cell disease with crisis (p=.02) and hemorrhage (p< .01) in NHB Patients. Among NHB patients – gestational hypertension [aOR: 1.61 (1.10 – 2.330], cesarean delivery [aOR: 2.82 (2.17 – 3.67)] and gestational age at delivery [aOR:1.87 (1.13 – 2.99)] were identified as key predictors of SMM. In NHW patients – gestational hypertension [aOR: 3.73 (1.88 – 7.16) and cesarean delivery [aOR: 3.71 (2.36 – 5.94)] had the highest impact on SMM risk.

Conclusion: Key clinical predictors of SMM were identified in our study with a differential risk impact among NHB and NHW patients as an opportunity for risk reduction and maternal mortality prevention.