Hypertension in pregnancy and later cardiovascular risk: common antecedents?

BACKGROUND: Preeclampsia and gestational hypertension are associated with increased risk for cardiovascular disease later in life. We have assessed whether the effect can be attributed to factors that operate in pregnancy or to prepregnancy risk factors that are shared by both disorders.

METHODS AND RESULTS: Longitudinal data from 2 consecutive waves of a Norwegian population-based study (the Nord-Trøndelag Health Study [HUNT]) were combined with data from the Medical Birth Registry of Norway. Among 24 865 women who had participated in both HUNT 1 and 2, we indentified 3225 women with a singleton birth between the 2 studies who had standardized measurements of blood pressure, serum lipids, and body mass index. The crude results showed that women who experienced preeclampsia or gestational hypertension in pregnancy had substantially higher levels of body mass index and systolic and diastolic blood pressures and unfavorable lipids compared with other women. However, after adjustment for prepregnancy measurements, the difference in body mass index was attenuated by >65%, and the difference in blood pressure was attenuated by approximately 50%. In relation to high-density lipoprotein cholesterol and triglycerides, differences between the groups were attenuated by 40% and 72%, respectively.

CONCLUSIONS: These results suggest that the positive association of preeclampsia and gestational hypertension with postpregnancy cardiovascular risk factors may be due largely to shared prepregnancy risk factors rather than reflecting a direct influence of the hypertensive disorder in pregnancy.