Preeclampsia—a serious complication of pregnancy characterized by high blood pressure in women whose blood pressure levels were normal—is one of the leading causes of maternal morbidity, responsible for some 70,000 maternal deaths and 500,000 fetal deaths worldwide each year. It occurs in approximately five percent of all pregnancies.
While it is known that Hispanic/Latina women develop hypertension disorders during pregnancy more frequently than whites, little research has been done to date to understand this health disparity or discover possible interventions to address it—until researchers from the Keck School of Medicine at the University of Southern California decided to look into the issue. The results of their study were published in February in the Journal of the American Heart Association.
To determine if a connection exists between diet and the likelihood of developing high blood pressure disorders during pregnancy, the researchers used data collected by the Maternal and Developmental Risks from Environmental and Social Stressors (MADRES), an ongoing prospective pregnancy cohort of predominantly low-income Hispanic women in the Los Angeles area. Of the 451 women involved in the study, 12% developed preeclampsia, about twice the national average.
“These findings are alarming and underscore the research need to determine factors driving this health disparity and identify effective interventions to prevent it,” said Luis E. Maldonado, PhD, MPH, the study’s lead author.
The subjects completed two questionnaires related to their consumption of food and beverages during the third trimester of pregnancy. Maldonado’s team also collected information on high blood pressure disorders from the women’s medical records.
Based on these diet interviews, the researchers identified two significant dietary patterns. In one, the most consumed foods were vegetables, oils, fruits, whole grains, and yogurt. In the second pattern, the women’s diet consisted primarily of solid fats, refined grains, cheese, added sugar, and processed meat. Perhaps not surprisingly, the results showed that women who adhered most to the second dietary pattern were four times as likely to develop hypertension during pregnancy. And the reverse was also true, as the women who adhered most to a diet composed primarily of vegetables and fruits were least likely to develop preeclampsia. Furthermore, the effect of eating a diet focused on vegetables, oils, and fruit was stronger in women who were overweight before their pregnancy, a known risk factor for preeclampsia.
Conclusions
Maldonado’s team noted that much more research needs to be done to uncover the relationship between ethnicity and the incidence of hypertensive disorders of pregnancy (HDP)and develop specific dietary guidelines.
“[T]he generalizability of our findings may be limited to low‐income Hispanic/Latina women in Los Angeles,” the researchers wrote in their conclusion. “Thus, studies…using larger population‐based samples of diverse Hispanic/Latina women are needed to evaluate differences in preeclampsia and other HDPs by geographic region.
“Future work is [also] needed to identify optimal relative intakes of foods to better inform dietary counseling during pregnancy for the prevention of HDPs among Hispanic/Latina women. Research evaluating HDP relationships with other theory‐driven diets (e.g., Dietary Approaches to Stop Hypertension) among this population are also needed.”
That said, the results do point to some practical steps that can be taken to reduce the incidence of preeclampsia. “Diet is a modifiable lifestyle factor which provides a potential intervention point during pregnancy,” said Maldonado. “Our findings suggest low-income Hispanic women at greater risk for preeclampsia may benefit from dietary guidance during prenatal visits to improve intakes of certain combinations of foods such as vegetables, oils, and fruit.”
