Early Preeclampsia Triples Risk of Hypertension
By Charles Bankhead, Staff Writer,
Published: August 26, 2011
Reviewed by Dori F. Zaleznik, MD; Associate Clinical Professor of Medicine, Harvard Medical School, Boston and
Dorothy Caputo, MA, RN, BC-ADM, CDE, Nurse Planner
Action Points
Explain that a study of cardiovascular risk factors 10 years after pregnancy showed that women who had preeclampsia before 32 weeks gestation had more than triple the risk of hypertension compared with controls who had a pregnancy without preeclampsia.
Note that meeting criteria for metabolic syndrome and waist circumference were also increased in those with a history of preeclampsia.
Preeclampsia before 32 weeks of gestation more than tripled a woman's odds of hypertension before age 40, a study of cardiovascular risk after preeclampsia showed.
Women who had developed preeclampsia had significantly higher mean systolic and diastolic blood pressure 10 years later than a matched control group of women who did not have preeclampsia, according to an article published online in the European Journal of Cardiovascular Prevention & Rehabilitation.
Women with a history of preeclampsia also had a twofold greater prevalence of metabolic syndrome. Waist circumference, too, was significantly greater in the preeclampsia group, which had a numerically greater body mass index (BMI).
Lipids, glucose, and C-reactive protein levels did not differ between women who had a history of preeclampsia and those who did not.
"The etiology of preeclampsia is as yet unresolved," Jose T. Drost, MD, of Isala Clinics in Zwolle, the Netherlands, and co-authors wrote in conclusion.
"Research on genetics and metabolic biomarkers is needed for a better understanding of its pathogenesis. Additional research should focus on the cost-effectiveness of cardiovascular screening programs and the timing of treatment of cardiovascular risk factors in women with previous preeclampsia."
Several studies have demonstrated associations between preeclampsia and future cardiovascular disease (CVD), and the magnitude of the association appears related to the severity of metabolic disturbances caused by preeclampsia.
Although the etiology of preeclampsia remains largely undetermined, early-onset preeclampsia (before 32 weeks of gestation) has a different pathophysiology than preeclampsia later in pregnancy, the authors wrote in their introduction.
Early preeclampsia induces an inflammatory response in the maternal circulation, leading to vasoconstriction and activation of the thrombotic cascade in the mother. Placental lesions associated with preeclampsia resemble early atherosclerosis, the authors continued.
In most cases, preeclampsia symptoms dissipate within a few weeks. However, decades later, women with a history of preeclampsia have at least a twofold greater risk of CVD.
Data from intermediate follow-up of women with a history of preeclampsia are scant, resulting in an uncertain time frame during which CVD risk factors develop. The lack of data is especially pertinent to the subgroup of women who develop the condition early in pregnancy, who might be targeted for early prevention.
Drost and colleagues sought to examine the emergence of CVD risk factors in women 10 years after an episode of early preeclampsia, defined as diastolic blood pressure ≥90 mmHg accompanied by proteinuria ≥0.3 g/24 h occurring before 32 weeks of gestation.
The study population consisted of women who responded to a mailed questionnaire and invitation to participate in a cardiovascular screening program. The investigators subsequently recruited 339 women with a history of early preeclampsia and 332 age-matched women with uncomplicated pregnancies.
Baseline characteristics included a mean age of 39 and mean interval of nine to 10 years since childbirth. Offspring of the preeclampsia group had a significantly lower mean birth weight (about 3.2 lbs versus 7.5 lbs, P<0.05), and the preeclampsia group had a significantly higher rate of stillbirth (14.8% versus 3.9%, P<0.05).
As compared with the control group, women with a history of early preeclampsia had significantly higher mean blood pressure (127/86 versus 119/79 mmHg, P<0.001 for systolic and diastolic pressure) and waist circumference (86.5 versus 83.2 cm, P=0.001) and a trend toward higher BMI (26.9 versus 26.2, P=0.066).
The authors reported that 43.1% of the preeclampsia group had hypertension (≥140/90 mmHg) as compared with 17.2% of the control group. The difference translated into an odds ratio of 3.5 for the preeclampsia group (P<0.001).
Fewer than half of the hypertensive women received adequate antihypertensive therapy (20.6% in the preeclampsia group versus 2.1% in the control group, P<0.05).
Twice as many women with a history of preeclampsia met diagnostic criteria for metabolic syndrome (18% versus 9%), resulting in an odds ratio of 2.18 (P=0.002).
No other clinical or metabolic parameters differed significantly between groups.
The authors cautioned that their findings cannot be extrapolated to women after 32 weeks of gestation with preeclampsia. There also may have been some bias as the women with preeclampsia were more motivated to participate than the controls, researchers said.