Impact of the maternal TG concentration in early pregnancy and pre-pregnancy BMI on the association between maternal blood pressure and risks of preeclampsia
We analyzed maternal TG concentrations in early pregnancy and pre-pregnancy BMI on the association between maternal blood pressure and the risk for preeclampsia in the 3 subgroups, categorized based on whether BMI ≥ 25 kg/m2 and/or a TG concentration > the 90th quartile. The absolute risk difference, AOR and 95% CI of each risk factor subgroups among the 4 blood pressure categories are shown in Figure 3 .
Among all the subgroups, elevated blood pressure was positively correlated with the risk of developing preeclampsia. Among women with a normal weight and TG concentration, the incidence of developing preeclampsia for those combined with stage 1 hypertension was 3.8%, in comparison to 1.2% in the “normal” blood pressure category. Women with stage 1 hypertension were nearly 3 times more likely to develop preeclampsia (AOR, 2.98; 95%CI: 2.63 to 3.39), and the risks rose up to 5.9 times for women with stage 2 hypertension (AOR, 5.91; 95% CI: 5.08 to 6.88).
Among women combined with either a BMI ≥ 25 kg/m2 or a TG concentration ≥ the 90th quartile, those with stage 1 hypertension were 5 times more likely to develop preeclampsia (AOR, 5.62; 95% CI: 4.80 to 6.58; risk difference, 5.7%; 95% CI: 3.6% to 7.9%), and the risk increased up to 10 times for women with stage 2 hypertension (AOR, 10.53; 95% CI: 8.87 to 12.50; risk difference, 11.5%; 95% CI: 9.4% to 13.6%) compared to those with “normal” blood pressure, combined with both a BMI < 25 kg/m2 and a TG concentration < the 90th quartile.
When the two risk factors coexisted, the risk of preeclampsia was significantly increased among all blood pressure ranges. Women with stage 1 hypertension were 6 times more likely to develop preeclampsia(AOR, 6.61; 95% CI: 4.87 to 8.97 with risk difference, 7.0%; 95% CI: 4.9% to 9.1%), and women with stage 2 hypertension had >13-fold increased risks of preeclampsia (AOR, 13.65; 95% CI: 10.31 to 18.08; risk difference of 15.0%; 95% CI: 13.5% to 16.6%) when compared to normotensive women with normal BMI and TG levels.