High blood pressure in pregnancy raises cardiac risks, according to new research from the University of Ottawa Heart Institute.
Women who experience high blood pressure disorders during pregnancy are at heightened risk of developing atrial fibrillation, a serious medical condition that can lead to stroke, heart failure and other complications. They are also at increased risk of early death, according to new research from the University of Ottawa Heart Institute.
The retrospective study followed more than 770,000 women in Ontario. It found that as early as seven years post-partum, those who had hypertensive disorders during pregnancy faced increased risk of atrial fibrillation (AFib) and death.
Hypertensive disorders of pregnancy include chronic hypertension (high blood pressure), gestational hypertension, preeclampsia, a serious complication of pregnancy, and eclampsia, which is a medical emergency.
“Hypertensive disorders of pregnancy are a group of conditions associated with high blood pressure during pregnancy and are major contributors to maternal death and serious health problems, both during and after pregnancy,” said Amy Johnston, an epidemiologist specializing in women’s cardiovascular and reproductive health was lead author of the study.
The study highlights the importance of recognizing hypertensive disorders of pregnancy as a significant cardiovascular risk factor for women, something that currently is not routinely done, said Jodi Edwards, director of the Brain and Heart Nexus Research Program at the Heart Institute, who co-led the research.
Pregnancy is considered a “vascular stress test” Edwards said. Previously, research has linked high blood pressure disorders during pregnancy to a higher risk of cardiac events such as heart attack and heart failure. But, until now, the heightened risk of AFib related to pregnancy hypertension disorders has “flown under the radar,” she said.
Atrial fibrillation is an irregular heartbeat, or arrhythmia that can lead to blood clots, stroke, heart failure and other heart-related complications. Women are at a significantly higher risk of developing AFib after menopause, which is one reason why the study’s findings of higher risk among relatively young women in the years following pregnancy stand out.
Edwards said the research uncovered more post-partum deaths than expected among women who experienced hypertensive disorders of pregnancy. Among 771,000 women studied, there were 3,000 deaths within seven years postpartum among women who had pregnancy hypertension disorders. That is a 0.4 per cent rate of death among women who experienced hypertensive disorders of pregnancy — higher than the 0.3 per cent of women who developed AFib.
The research showed that women who experience hypertensive disorders of pregnancy were almost twice as likely to develop AFib compared to those who did not. Those with the most serious disorders as well as those with prepregnancy chronic hypertension had a higher risk of developing AFib within seven years postpartum.
Edwards said a key takeaway is that pregnancy hypertensive disorders must be considered risk factors for cardiovascular disease and women who experience them must be closely monitored for heart issues with better screening than currently exists.
She said understanding the risk can lead to early treatment that could prevent more serious outcomes.
“Why are we waiting until people have a stroke?”
The study, conducted by researchers from the University of Ottawa Heart Institute, was published in a special edition of the journal Circulation focused on women’s heart health.
