Maternal nativity and disparities in preeclampsia

A cross-sectional analysis of the Boston Birth Cohort (BBC) from 1998 to 2016 has found that maternal nativity and duration of United States residence were linked to preeclampsia among non-Hispanic Black women, but not among Hispanic and non-Hispanic White women, after adjusting for sociodemographic and cardiovascular risk factors.

The analysis in JAMA Network Open also determined that U.S.-born Hispanic, non-Hispanic Black, and non-Hispanic White women had worse cardiovascular risk profiles compared to their counterparts born outside the U.S.1

“These findings suggest that nativity-related disparities in preeclampsia among non-Hispanic Black women are not fully explained by nativity differences in sociodemographic and cardiovascular risk factors,” wrote the authors.

The racially diverse cohort of 6,096 women, with a mean age of 27.5 years, comprised non-Hispanic Black (n = 2,699), Hispanic (n = 2,400), and non-Hispanic White (n = 997).

All the women had singleton deliveries at the Boston Medical Center. Maternal nativity and duration of U.S. residence (less than 10 years vs. at least 10 years) were self-reported.

The prevalence of preeclampsia was 9.5%, which is considerably higher than the 3.8% to 5.0% reported nationally, due to BBC being a high-risk cohort that oversamples women with preterm deliveries and has a high percentage of Black women.

Non-Hispanic Black women had the highest incidence of chronic hypertension (7.5% vs 2.7% for Hispanic and 2.8% for non-Hispanic White women); obesity (24.4% vs 15.8% and 15.2%, respectively); and preeclampsia (11.0% vs 8.8% and 7.1%, respectively).

U.S.-born women in all 3 racial and ethnic groups also had a significantly higher prevalence of obesity (23.7% for Hispanic women vs 13.4% for those born outside the U.S.; 27.6% for non-Hispanic Black women vs 19.6%, respectively; and 17.0% for non-Hispanic White women vs 9.0%, respectively); smoking (17.6% for Hispanic women vs 1.6%, respectively; 20.5% for non-Hispanic Black women vs 4.9%, respectively; and 49.2% for non-Hispanic White women vs 19.0%, respectively); and severe stress (13.7% for Hispanic women vs 4.6%, respectively; 14.4% for non-Hispanic Black women vs 11.0%, respectively; and 21.1% for non-Hispanic White women vs 11.8%, respectively).

After adjusting for sociodemographic and cardiovascular risk factors, non-Hispanic Black women who were born outside the U.S. and had a shorter duration of U.S. residence were less likely to develop preeclampsia: adjusted odds ratio (aOR) = 0.74, 95% confidence interval (CI): 0.55 to 1.00; and aOR = 0.62, 95% CI: 0.41 to 0.93, respectively.

However, among Hispanic and non-Hispanic White women, maternal nativity and duration of U.S. residence were not connected to preeclampsia.

Differences in sociodemographic and cardiovascular risk factors might be the reason for nativity-related differences in the prevalence of preeclampsia among non-Hispanic White and Hispanic women, according to the authors. But they noted that nativity-related disparities in preeclampsia among non-Hispanic Black women are more complex, perhaps driven in part by chronic stress due to racism, health care access, and segregation, as well as the lack of social support for native-born non-Hispanic Black women.

“Thus, interventions focused on stress reduction and improvements in social support may positively affect pregnancy outcomes among non-Hispanic Black women,” wrote the authors.

The authors said that particularly among non-Hispanic Black women, additional research is needed to explore the interplay of factors contributing to nativity-related disparities in preeclampsia.

Reference

Boakye E, Kwapong YA, Obisesan O, et al. Nativity-related disparities in preeclampsia and cardiovascular disease risk among a racially diverse cohort of US women. JAMA Netw Open. Published online December 20, 2021. doi:10.1001/jamanetworkopen.2021.39564