Mediterranean-Style Diet Can Reduce Preeclampsia Risk

Anum Minhas, MD, MHS

New research suggests adherence to a Mediterranean-style diet could lower a woman’s risk of developing preeclampsia by more than 20%.

An analysis of data from women enrolled in the Boston Birth Cohort, results of the study indicate greater adherence to a Mediterranean-style diet was associated with a 22% reduction in odds of developing preeclampsia, with the magnitude of reduction growing to 28% when assessing increased adherence among Black women in the study.

“The US has the highest maternal mortality rate among developed countries, and preeclampsia contributes to it,” said Anum S. Minhas, MD, MHS, chief cardiology fellow and a cardio-obstetrics and advanced imaging fellow at Johns Hopkins University, in a statement. “Given these health hazards to both mothers and their children, it is important to identify modifiable factors to prevent the development of preeclampsia, especially among Black women who are at the highest risk of this serious pregnancy complication.”

Among the most common metabolic disorders of pregnancy, preeclampsia poses a significant threat to the overall health of women. With this in mind, better understanding of modifiable risk factors, including diet, for preeclampsia stands to have a significant impact on an individual and population level. Led by Minhas and a team of colleagues from Johns Hopkins University, the current study was designed to assess whether a Mediterranean-style diet would provide a protective benefit against preeclampsia among a cohort of racial and ethnically diverse women from low-income, urban areas.

To do so, investigators designed their study as an analysis of data from the Boston Birth Cohort. A prospective birth cohort study consisting of 8500 mother-infant pairs, the study provided investigators with data related to a cohort of 8507 women for inclusion in their analyses, including 848 who developed preeclampsia. From the Boston Birth Cohort, investigators obtained data related to maternal sociodemographic information, clinical information, and dietary information for all subjects included in the present study. Of note, dietary information was obtained via interview and food frequency questionnaires conducted within 24-72 hours postpartum.

For the purpose of analysis, investigators categorized patients into tertiles based on their Mediterranean-style diet score (MSDS), which was created using data from the food frequency questionnaire. The first tertile corresponds to an MSDS of 4-23, second tertile to an MSDS of 24-26, and the third tertile to an MSDS of 27-38. Initial analyses indicated a greater percentage of women in the lowest MSDS tertile (11%) had preeclampsia compared to the middle (9%) and highest tertiles (10%).

In multivariable-adjusted analyses, those with the greatest adherence to a Mediterranean-style diet was associated with lower preeclampsia odds, with those in third tertile of MSDS at a 22% lower risk of preeclampsia than those in the first tertile (aOR, 0.78 [95% CI, 0.64-0.96]). Further analysis according to race and ethnicity revealed the benefit was similar among Black women when comparing the third tertile to first tertile (aOR, 0.74 [95% CI, 0.76-0.96]). However, this reduction in risk was not as apparent in non-Black women (aOR, 0.81 [95% CI, 0.62-1.05]).

“We were surprised that women who more frequently ate foods in the Mediterranean-style diet were significantly less likely to develop preeclampsia, with Black women experiencing the greatest reduction in risk,” Minhas said. “This is remarkable because there are very few interventions during pregnancy that are found to produce any meaningful benefit, and medical treatments during pregnancy must be approached cautiously to ensure the benefits outweigh the potential risks to the mother and the unborn child.”

This study, “Mediterranean-Style Diet and Risk of Preeclampsia by Race in the Boston Birth Cohort,” was published in the Journal of the American Heart Association.