Maternal morbidity rates lower on treatment
Severe SGA, which was defined as below the 5th percentile, was also numerically but not significantly higher in the control arm than in the group receiving treatment (5.1% vs. 5.5%), but the incidence of composite adverse maternal events was numerically lower (2.1% vs. 2.8%). The incidences of all components of maternal morbidity, such as maternal death (0.1% vs. 0.2%) pulmonary edema (0.4% vs. 0.9%), heart failure (0.1% vs. 0.1%), and acute kidney injury (0.8% vs. 1.2%), were either lower or the same on active treatment versus no treatment.
According to Dr. Tita, who called CHAP one of the largest and most diverse studies to address the value of treating mild hypertension in pregnancy, the American College of Obstetricians and Gynecologists (ACOG) is evaluating these data for changing their current guidelines for managing hypertension during pregnancy.
“The rate of chronic hypertension during pregnancy has been rising in the United States due to the increase in the average age of pregnant women and the rising rates of obesity,” Dr. Tita commented.
“We definitely needed these data,” said Mary Norine Walsh, MD, medical director, Ascension Saint Vincent Cardiovascular Research Institute, Indianapolis. Not only has the value of treating mild hypertension been unresolved, but Dr. Walsh pointed out that the rates of maternal mortality in the United States are rising and now generally exceed those of many other developed countries.
There are several features in the design of this trial that make the results even more salient to clinical practice, according to Dr. Walsh. This includes the fact that about half of patients enrolled were on Medicaid. As a result, the study confirmed benefit in what Dr. Walsh characterized as a “vulnerable” population.
“We will be busy now to make sure that our [pregnant] patients are achieving these target blood pressures,” Dr. Walsh said. She indicated that CHAP validates the treatment target of 140/90 mm Hg as a standard of care.
The results were published in the New England Journal of Medicine simultaneously with its ACC presentation.
The trial was funded by the National Heart, Lung, and Blood Institute. Dr. Tita reports research grants from Pfizer. Dr. Walsh reports a financial relationship with EBR Systems. Dr. Poppas reports no potential conflicts of interest.