Clinical value of 24-h ambulatory blood pressure monitoring for delivery of small for gestational age infants in preeclampsia

Abstract

Objective To explore the values of 24-h ambulatory blood pressure monitoring (ABPM) in predicting delivery of small for gestational age (SGA) infants of pregnant women with preeclampsia (PE). Methods A total of 733 pregnant women with PE who gave birth in Guangdong Maternal and Child Health Hospital from June 2015 to June 2017 were selected into this study. According to SGA infants and AGA infants delivered by PE pregnant women, they were divided into group A (n=399, PE pregnant women delivered SGA infants) and group B (n=334, PE pregnant women delivered AGA infants). The following items, such as maternal age, pre-pregnancy body mass index (BMI), gestational age at delivery, fetal birth weight, glycosylated hemoglobin (HbA1c), triacylglycerol (TG), low-density lipoprotein (LDL), diastolic blood pressure, systolic blood pressure, day systolic blood pressure (dSBP), night systolic blood pressure (nSBP), 24-h systolic blood pressure (24-h SBP), day diastolic blood pressure (dDBP), night diastolic blood pressure (nDBP), and 24-h diastolic blood pressure (24-h DBP), were compared by independent-samples t test between two groups. The indexes, such as systolic nocturnal pressure drop rate (SBP-DR) and diastolic nocturnal pressure drop rate (DBP-DR), were compared between two groups by using Mann-Whitney U test. Univariate and multivariate unconditional logistic regression analysis were used to analyze the relative factors associated with blood pressure in pregnant women with PE. The area under the receiver operating characteristic (ROC) curve (ROC-AUC) was calculated using the prediction model constituted by each parameter with statistically significant difference by using the roccomp command in Stata 15.0 statistical software, and multiple ROC curve comparisons were performed. The procedures followed in this study were in accordance with the World Medical Association Declaration of Helsinki as revised in 2013, and informed consent for the clinical study was obtained from all subjects. Results ① Univariate analysis showed that there were significant differences in age, pre-pregnancy BMI, gestational age at delivery, fetal birth weight, HbA1c, TG, TC, LDL, diastolic blood pressure, and nSBP, 24-h SBP, dDBP, nDBP, 24-h DBP, 24-h DBP, SBP-DR, and DBP-DR between two groups (t=3.112, 2.564, 13.901, 27.073, 3.436, -2.165, -3.690, -3.021, -3.825, -2.557, -4.836, -7.423, -6.024, Z=4.221, 5.703; P<0.05). ②Univariate logistic regression analysis showed that diastolic pressure, nSBP, SBP, dDBP, nDBP, and 24-h DBP of PE pregnant women were independent risk factors for SGA (OR=1.118, 95%CI: 1.039-1.203, P=0.003; OR=1.216, 95%CI: 1.098-1.347, P<0.001; OR=1.172, 95%CI: 1.036-1.326, P=0.011; OR=1.221, 95%CI: 1.123-1.327, P<0.001; OR=1.287, 95%CI: 1.198-1.383, P<0.001; OR=1.282, 95%CI: 1.178-1.296, P<0.001). Multivariate unconditional logistic regression analysis showed that nSBP, 24-h SBP, dDBP, nDBP and 24-h DBP of PE pregnant women were independent risk factors for SGA (OR=1.265, 95%CI: 1.135-1.410, P<0.001; OR=1.238, 95%CI: 1.085-1.412, P=0.002; OR=1.221, 95%CI: 1.120-1.331, P<0.001; OR=1.289, 95%CI: 1.197-1.388, P<0.001). ③ The results of multiple ROC curve analysis showed that the ROC-AUC of nDBP in 24-h ABPM parameters was 0.694, which was significantly larger than 0.646 of CBP diastolic pressure, and the difference was statistically significant (χ2=8.982, P=0.003). Conclusions The nDBP in 24-h ABPM parameters is closely related to the delivery of SGA of pregnant women with PE, which provides a new idea for blood pressure management in pregnant women with PE. Key words: Pre-eclampsia; Blood pressure determination; Hypertension, pregnancy-induced; Infant, small for gestational age; Pregnant women