WEDNESDAY, March 10, 2021 (HealthDay News) -- High blood pressure during pregnancy may lead to early death from heart disease, a new study suggests.
There are several types of high blood pressure (also known as hypertension) during pregnancy. Chronic hypertension means high blood pressure was already present before a pregnancy, but in gestational hypertension readings rise during pregnancy. A third form, called preeclampsia, occurs when a woman with gestational hypertension also has elevated protein in her urine. Women can also have chronic high blood pressure with preeclampsia.
But developing high blood pressure from any cause during pregnancy appears linked to shortened life spans, the researchers found. This study can't prove that high blood pressure is the cause of premature death, only that there appears to be a link. The factors behind that aren't yet clear.
"It is important that additional research identifies these contributing factors, and that clinicians taking care of women are aware of the link between hypertension in pregnancy and later cardiovascular health," said lead researcher Dr. Jorge Chavarro. He's associate professor of nutrition and epidemiology at Harvard T.H. Chan School of Public Health, in Boston.
For the study, Chavarro's team collected data on nearly 88,400 women who took part in a long-term study of nurses' health.
The findings showed that 14% of the women had high blood pressure during pregnancy.
Those with high blood pressure or preeclampsia were more likely than other women to be heavier, have gestational diabetes and a parental history of diabetes and heart attack or stroke, the study found.
During 28 years of follow-up, nearly 2,400 women died prematurely, including 212 from heart or blood vessel disease, according to the report published online March 8 in the Journal of the American College of Cardiology.
A history of high blood pressure or preeclampsia was linked to a 42% higher risk for early death. The link remained after accounting for diet after pregnancy, lifestyle and reproductive characteristics.
Women with a history of high blood pressure during pregnancy had more than twice the risk of premature death from heart disease, the study authors found.
"It is really important for clinicians who should be aware not only of the link between hypertension during pregnancy and long-term adverse health outcomes, but also that this may happen even in the absence of chronic hypertension," Chavarro said.
Dr. Suzanne Steinbaum, a spokeswoman for the American Heart Association, called the findings significant.
"This is an important study, really showing the profound impact of hypertension disorders in pregnancy … and the profound impact that plays on outcomes for her and her risk for cardiovascular disease is incredibly important to understand," said Steinbaum, a cardiologist at the Juhi-Ash Integrative Health Center in New York City.
Pregnancy is the first stress test women undergo to determine their risk of heart disease, she said. Because heart disease develops over decades, this is most likely the start of small artery disease, which is also associated with weight, family history and chronic high blood pressure.
"Those risk factors are already in place, and what it means is this woman already has the predisposition to develop heart disease, whether it's due to her genetics or her risk factors, but that's what makes pregnancy and looking at it as a stress so interesting, because it's the first time you get to say, 'I can intervene now, and this woman doesn't get to have heart disease,' we can change her outcomes," Steinbaum said.
Prevention starts early, she said. Women need to know their risks and get their blood pressure, cholesterol and blood sugar levels checked.
"The concept of lifestyle intervention from eating healthy and exercising is the best medication for reducing risk factors and preventing cardiovascular disease," Steinbaum said.
"I would suggest that for these women, they go through a lifestyle intervention program prior to even getting pregnant," she added.
Learn more about high blood pressure during pregnancy from the U.S. Centers for Disease Control and Prevention.
SOURCES: Jorge Chavarro, MD, associate professor, nutrition and epidemiology, Harvard T.H. Chan School of Public Health, Boston; Suzanne Steinbaum, DO, Juhi-Ash Integrative Health Center, New York City, and spokeswoman, American Heart Association; Journal of the American College of Cardiology, March 8, 2021, online