Preeclampsia and CV risk: Which is the chicken and which is the egg?

Consider a history of preeclampsia when calculating your patients' risk for cardiovascular disease, suggest the findings of a systematic review and meta-analysis.

Researchers from London analyzed 25 prospective and retrospective cohort studies yielding a dataset of more than 3 million women, 200,000 of whom experienced preeclampsia.

The researchers calculated that at various points during the 15 years after having preeclampsia women become almost four times as likely to develop hypertension (RR 3.7; 95% CI, 2.70–5.05), twice as likely to develop fatal and nonfatal ischemic heart disease (RR 2.16; 95% CI, 1.86–2.52), and almost twice as likely to develop a stroke (RR 1.81; 95% CI, 1.45–2.27) or venous thromboembolism (RR 1.79; 95% CI, 1.37–2.33), when compared to women who have never had preeclampsia. These women are also one-and-a-half times more likely to die, largely because of the increased risk for cardiovascular disease. Developing preeclampsia before 37 weeks' gestation increases the risk for future cardiovascular disease even more.

A separate Norwegian population-based cohort study involving 3,494 women found that women with cardiovascular risk factors, present in some cases years before pregnancy, may be at increased risk for preeclampsia.

In fact, researchers calculated that women with baseline systolic blood pressures >130 mm Hg were more than seven times as likely as women with systolic BP <111 mm Hg to develop preeclampsia (OR 7.3; 95% CI, 3.1–17.2), regardless of parity. They also found positive associations between the risk for preeclampsia and diastolic BP, cholesterol, low-density lipoprotein cholesterol, and triglycerides. Interestingly, women using oral contraceptives at baseline had half the risk for preeclampsia of never and former users of OCs.

An accompanying editorial points out that even with the increased risk for CV disease found in the first study, the risks for CV disease and death are still low (hypertension 21.9%, ischemic heart disease 0.2%, stroke 0.2%, venous thromboembolic disease 0.3%, death 1.4%) in this group of women. And given that many of them are quite young, they provide a unique opportunity for primary prevention. The author of the editorial says that these women should be screened early for traditional risk factors and that difficult pregnancies and/or deliveries due to preeclampsia may motivate them to make necessary lifestyle changes.

Bellamy L, Casas JP, Hingorani AD, et al. Pre-eclampsia and risk of cardiovascular disease and cancer in later life: systematic review and meta-analysis. BMJ. 2007;335:974.

Magnussen EB, Vatten LJ, Lund-Nilsen TI, et al. Prepregnancy cardiovascular risk factors as predictors of preeclampsia: population based cohort study. BMJ. 2007;335:978.

Magee LA, von Dadelszen P. Preeclampsia and increased cardiovascular risk: guidelines for primary prevention of cardiovascular disease are appropriate for all women. BMJ. 2007;335:945-946.