Formerly eclamptic women have lower nonpregnant blood pressure compared with formerly pre-eclamptic women: a retrospective cohort study

Abstract

Objective: To compare nonpregnant blood pressure and circulating metabolic factors between formerly pre-eclamptic women who did and did not deteriorate to eclampsia.

Design: Retrospective observational cohort study.

Setting: Tertiary referral centre.

Population: Formerly pre-eclamptic women with (n = 88) and without (n = 698) superimposed eclampsia.

Methods: Women who experienced pre-eclampsia with or without superimposed eclampsia during their pregnancy or puerperium were tested for possible underlying cardiovascular risk factors at least 6 months postpartum. We measured blood pressure and determined cardiovascular and metabolic risk markers in a fasting blood sample. Groups were compared using Mann-Whitney U test, Spearman's Rho test or Fisher's Exact test (odds ratios).

Main outcome measures: Differences in postpartum blood pressures and features of the metabolic syndrome between formerly pre-eclamptic and formerly eclamptic women.

Results: Formerly pre-eclamptic women who developed eclampsia differed from their counterparts without eclampsia by a lower blood pressure (P < 0.01) with blood pressure correlating inversely with the likelihood of having experienced eclampsia (P < 0.001). In addition, formerly eclamptic women had higher circulating C-reactive protein levels than formerly pre-eclamptic women (P < 0.05). All other circulating metabolic factors were comparable. Finally, 40% of all eclamptic cases occurred in the puerperium.

Conclusions: Formerly pre-eclamptic women with superimposed eclampsia have lower nonpregnant blood pressure compared with their counterparts without neurological sequelae with blood pressure negatively correlated to the occurrence of eclampsia. As about 40% of all eclamptic cases occur postpartum, routine blood pressure monitoring postpartum should be intensified.

Keywords: Blood pressure; eclampsia; pre-eclampsia.

Figure 1

Percentages of the occurrence of eclampsia (E) versus preeclampsia (PE) arranged in quintile groups of the mean arterial blood pressure (MAP). Graph showing trend-analysis that demonstrates a significant negative correlation between MAP and the occurrence of eclampsia (E). In addition, graph showing odds ratio of 2^nd to 5^th quintile group compared to the lowest quintile group of the MAP. Odds ratios show a decreased risk of the occurrence of eclampsia when increasing MAP in the different population quintiles that is reaching statistical difference in the 4^th and 5^th quintile group (p < 0.05). Population Quintiles and corresponding MAP: <p20: MAP < 79 mmHg; p20–40: MAP 79–84 mmHg; p40–60: MAP 84–89 mmHg; p60–80: MAP 89–97 mmHg; >P80: MAP > 97 mmHg.