Research published in the Journal of the American Heart Association reveals significant disparities in pregnancy-related high blood pressure risk among Asian American, Native Hawaiian and Pacific Islander subgroups. The study, which analyzed California health records from 2007-2019, found that Pacific Islander and Filipino individuals faced two to three times higher risk than Chinese individuals, after adjusting for sociodemographic and maternal-health factors.
The analysis examined 772,688 pregnant individuals who self-identified as Asian American, Native Hawaiian or Pacific Islander, divided into 15 subgroups. Researchers reviewed records for five hypertensive disorders of pregnancy: chronic hypertension, gestational hypertension, preeclampsia, eclampsia, and chronic hypertension with preeclampsia. The findings showed the lowest frequency of pregnancy-related high blood pressure in the Chinese subgroup at 3.7%, while the Guamanian subgroup had the highest frequency at 13%.
"There are known ways to help prevent and treat high blood pressure during pregnancy. Our findings can help health care professionals identify those who are at higher risk," said study lead author Jennifer Soh, M.S., formerly of Stanford University School of Medicine. "Early identification and treatment can help prevent serious, downstream complications for both the pregnant individuals and their infants."
Pregnancy-related high blood pressure increases the risk of heart attack and stroke and is one of the leading causes of maternal illness and death, according to the U.S. Centers for Disease Control and Prevention. In the United States, about 1 in 7 pregnancies are affected by a high blood pressure-related condition during pregnancy. These conditions can be managed and treated with medication or lifestyle changes, according to the American Heart Association.
The study found that using the Chinese population as the reference point, the risk of pregnancy-related high blood pressure conditions was elevated among Filipino and Pacific Islander populations: Hawaiian, Guamanian, Samoan and other Pacific Islander individuals. Only Japanese, Korean and Vietnamese individuals tended to have risks that were not elevated compared to the Chinese reference group.
Previous research has indicated that the risk of developing pregnancy-related high blood pressure differs among people of different races and ethnicities due to social determinants of health. Yet little has been known about differences in risk between Asian American, Native Hawaiian and Pacific Islander populations as they are often studied together, despite the diversity found within these groups. The American Heart Association provides comprehensive health information about pregnancy and maternal health at https://www.heart.org/en/health-topics/pregnancy.
"The observed racial-ethnic differences in risk highlight the variation in lived experiences of the individuals included in this study," Soh said. "Future studies should examine more structural and social factors that could help explain the differences in the elevated risks found in this study."
The study had several limitations. It relied on medical diagnostic codes, which may be subject to underreporting or misclassification; the data only included individuals in California, so the results may not apply to other people living in different communities; and the study could not account for the effects of the COVID-19 pandemic, since the pandemic began after the study period. Additionally, the study could not consider additional potential factors that may impact high blood pressure during pregnancy, such as air pollution, neighborhood walkability and food access.
Researchers used statistical tools to determine the relative risks of the hypertensive disorders of pregnancy within each subgroup. The average age of individuals included in the study was 32 years. The American Heart Association's financial information is available at https://www.heart.org/en/about-us/aha-financial-information.
These findings have significant implications for maternal healthcare, suggesting that blanket approaches to pregnancy-related hypertension prevention may be inadequate for diverse populations. The research underscores the importance of disaggregating health data to better understand and address health disparities within broadly categorized racial and ethnic groups.
