Eirin Beate Haug has used data from the population-based HUNT study to investigate cardiovascular health prior to and after pregnancies in more than 20,000 women.
MAIN RESULTS:
- Mothers have lower blood pressure at the age of 50 than women without children.
- Already before they get pregnant, women who later get preeclampsia have increased cardiovascular risk.
- Increased BMI and blood pressure among women with previous hypertensive disorders in pregancy explains most of the increased risk of cardiovascular disease.
THESIS DEFENCE:
Thesis: A life course study of the relationship between pregnancy and cardiovascular health in women: The HUNT study in Norway
Candidate: Eirin Beate Haug
Time: December 20, 2018 at 12:15
Place: St. Olavs Hospital, Medical Technical Research Center: Auditorium MTA
Link to university website (in Norwegian)
SUMMARY:
(1) Pregnancies could reduce the blood pressure so much in the long-term that it is clinically important. Before the first pregnancy, women who later gave birth had similar blood pressure to those who never had children. After the first pregnancy, the blood pressure decreased significantly, and in women who had more children there was a small reduction following every subsequent birth. At 50 years of age, the blood pressure remained lower in women with than in women without children.
The study includes a total of 23,438 women who participated in at least two HUNT surveys between 1984 and 2008.
(3) Pregnancy is associated with adverse and long-lasting changes in HDL-cholesterol. The same methodology and sample as in the first article was used to examine these associations, and Haug and colleagues found a marked drop of 7 % in HDL-cholesterol levels following the first pregnancy. The changes were larger in women who did not breast feed, and persisted beyond the age of 50. Non-HDL-cholesterol and triglycerides did not change.
(2) Women who have preeclampsia in their first pregnancy have increased levels of risk factors for cardiovascular disease already before they get pregnant. Compared to women who do not get preeclampsia, they have more body fat, higher blood pressure, higher resting heart rate, higher blood glucose and higher lipid levels. Generally, women with pregnancies complicated by preeclampsia have the same cardiovascular risk ten years earlier in life than those who have never had preeclampsia.
22,308 women with a normotensive first pregnancy, 1092 with preeclampsia, and 478 with gestational hypertension in their first pregnancy were included. Haug and colleagues linked information on cardiovascular risk factors from the HUNT surveys with information on pregnancy from the Medical Birth Registry of Norway. Women with gestational hypertension had approximately the same risk factor profile as those with preeclampsia.
(4) 40–70 years old women with previous preeclampsia or gestational hypertension have 60 % increased risk of cardiovascular disease compared to age-matched women without hypertensive preganancy disorders. Higher BMI and blood pressure explains 75 % of this increased risk.
REFERENCES:
(1) Haug, E. B., Horn, J., Markovitz, A. R., Fraser, A., Macdonald-Wallis, C., Tilling, K., Romundstad, P., Rich-Edwards, J. W., & Åsvold, B. O. (2018). The impact of parity on life course blood pressure trajectories: the HUNT study in Norway. European journal of epidemiology, 1-11.
(2) Haug, E. B., Horn, J., Markovitz, A. R., Fraser, A., Vatten, L. J., Macdonald‐Wallis, C., Tilling, K., Romundstad, P., Rich-Edwards, J. W., & Åsvold, B. O. (2018). Life Course Trajectories of Cardiovascular Risk Factors in Women With and Without Hypertensive Disorders in First Pregnancy: The HUNT Study in Norway. Journal of the American Heart Association, 7(15), e009250.
(3) Markovitz, A. R., Haug, E. B., Horn, J., Fraser, A., Macdonald-Wallis, C., Tilling, K., Rimm, E. B., Missmer, S. A., Williams, P. L., Romundstad, P. R., Åsvold, B. O., & Rich-Edwards, J. W. (2018). Does pregnancy alter life-course lipid trajectories? Evidence from the HUNT Study in Norway. Journal of lipid research, 59(12), 2403-2412.
(4) Haug, E. B., Horn J., Markovitz, A. R., Fraser, A., Vatten, L., Klykken, B., Dalen, H., Romundstad, P. R., Rich-Edwards, J. W., & Åsvold B. O. Cardiovascular disease after hypertensive pregnancy disorders: the role of conventional cardiovascular risk factors. The HUNT study in Norway (Currently unpublished)