Obesity Marks Higher Circulating Endothelin-1 in Severe Preeclampsia: A Multicenter Cross-Sectional Analysis

Abstract

Background: Obesity and severe preeclampsia share inflammatory, oxidative, and endothelial pathways, but it is uncertain whether obesity is accompanied by additional endothelin-1 (ET-1) elevation once severe preeclampsia is already present.
Objective: To examine circulating ET-1 according to pre-pregnancy obesity status and obesity class among women with severe preeclampsia.
Methods: A multicenter cross-sectional analysis was conducted in 88 women with severe preeclampsia recruited consecutively from four hospitals in South Sulawesi, Indonesia, between May 2025 and March 2026. Pre-pregnancy BMI was classified using the prespecified Asia-Pacific cutoffs (non-obesity, <25.0 kg/m²; class I obesity, 25.0–29.9 kg/m²; class II obesity, ≥30.0 kg/m²). ET-1 was quantified by ELISA, and non-parametric tests were used because ET-1 was not normally distributed.
Results: Women with obesity had higher ET-1 than women without obesity (median [IQR] 3.38 [0.65–27.11] pg/mL vs 0.76 [0.49–2.70] pg/mL, p=0.019). Within the obesity group, class I and class II obesity showed similar ET-1 distributions (3.77 [0.70–22.40] pg/mL vs 3.28 [0.51–37.01] pg/mL, p=0.567). No statistically significant ET-1 differences were detected across age, parity, or gestational-age categories.
Conclusion: Pre-pregnancy obesity was associated with higher circulating ET-1 among women with severe preeclampsia, whereas class I and class II obesity did not differ. These findings support endothelial heterogeneity associated with maternal adiposity but do not establish causality or clinical predictive value.