Levels of blood pressure, cardiovascular biomarkers and their correlations in women with previous pre-eclamptic pregnancy within 7 years postpartum: a cross-sectional study in Thailand

Abstract

Objective: To assess the levels of blood pressure, cardiovascular biomarkers and their correlations measured within 7 years postpartum in women with previous pre-eclamptic pregnancies compared with women with previous normotensive pregnancies.

Design: Cross-sectional study.

Setting: Two tertiary hospitals in the southern region of Thailand.

Participants: Women with pre-eclamptic and normotensive pregnancies in the past 7 years were enrolled from 1 October 2019 to 30 April 2021. Eligible women were interviewed, examined for body mass index (BMI) and blood pressure, and donated morning spot urine and blood samples.

Primary outcome measures: Serum high-sensitivity C reactive protein, creatinine, fasting blood glucose (FBS), glycated haemoglobin (HbA1c), low-density lipoprotein (LDL) cholesterol, urine microalbumin to creatinine ratio (UACR) and sodium were measured. Group differences in biomarkers were tested using unpaired t-test, Wilcoxon rank-sum test or χ² test. The levels of blood pressure and biomarkers between the two study groups at <2 years, 2-4 years and >4 years were also compared. The correlations between blood pressure and biomarkers were analysed using Pearson's correlation and partial correlation methods.

Results: From 206 women included in the analysis, 88 had pre-eclamptic pregnancies and 118 had normotensive pregnancies. Compared with women with previous normotensive pregnancies, women with previous pre-eclamptic pregnancies had significantly increased rates of hypertension (31.8% vs 7.6%, p<0.001) and obesity (55.7% vs 40.7%, p=0.038), as well as higher serum levels of FBS (p<0.001), HbA1c (p<0.001), LDL cholesterol (p=0.03), creatinine (p<0.001) and UACR (p<0.001). Correlation coefficients of BMI, serum creatinine and UACR with blood pressure ranged from 0.27 to 0.31.

Conclusion: The risk of hypertension after a pre-eclamptic pregnancy increased. Blood pressure measurement combined with BMI, serum creatinine and UACR screening at least once during 7 years postpartum is suggested for early detection of cardiovascular risk.

Keywords: epidemiology; hypertension; maternal medicine.