WASHINGTON – Cardiovascular risk factors may be elevated “as soon as the first postpartum year” in women who have gestational diabetes or hypertensive disorders of pregnancy, recent findings have affirmed, said at the biennial meeting of the Diabetes in Pregnancy Study Group of North America.
Dr. Ehrenthal was one of several researchers who urged innovative strategies and improved care coordination to boost women’s follow-up after gestational diabetes mellitus (GDM) and other adverse pregnancy outcomes and complications. “The metabolic stress of pregnancy can uncover underlying susceptibilities,” she said. “And”
Evidence that adverse pregnancy outcomes – including GDM and hypertensive disorders of pregnancy (HDP) – can elevate cardiovascular risk comes most recently from the Nulliparous Pregnancy Outcomes Study – Monitoring Mothers to be Heart Health Study (nuMoM2b–HHS study), a prospective observational cohort that followed 4,484 women 2-7 years after their first pregnancy. Women had a follow-up exam, with blood pressure and anthropometric measurements and clinical/biological testing, an average of 3 years post partum.
An analysis published in October 2019 in the Journal of the American Heart Association shows that women with HDP (including preeclampsia and gestational hypertension) had a relative risk of hypertension of 2.5 at follow-up, compared with women without HDP. Women who had preeclampsia specifically were 2.3 times as likely as were women who did not have preeclampsia to have incident hypertension at follow-up, said Dr. Ehrenthal, a coinvestigator of the study.
The analysis focused on incident hypertension as the primary outcome, and adjusted for age, body mass index, and other important cardiovascular disease risk factors, she noted. Researchers utilized the diagnostic threshold for hypertension extant at the time of study design: A systolic blood pressure of 140 mm Hg or greater, or a diastolic BP of 90 mm Hg or greater ().
HDP was the most common adverse pregnancy outcome in the nuMoM2b–HHS study (14%). Among all participants, 4% had GDM. Approximately 82% had neither HDP nor GDM. Other adverse pregnancy outcomes included in the analysis were preterm birth, small-for-gestational-age birth, and stillbirth.
Additional preliminary estimates presented by Dr. Ehrenthal show that, based on the new (2017) lower threshold for hypertension – 130 mg Hg systolic or 80 mm Hg diastolic – the disorder afflicted 37% of women who had experienced HDP (relative risk 2.1), and 32% of women who had GDM (RR 1.8). Prediabetes/diabetes (using a fasting blood glucose threshold of 100 mg/dL) at follow-up affected an estimated 21% of women who had HDP (RR 1.4) and 38% of women who had GDM (RR 2.5).
Notably, across the entire study cohort, 20% had hypertension at follow-up, “which is extraordinary” considering the short time frame from pregnancy and the young age of the study population – a mean maternal age of 27 years, said Dr. Ehrenthal, associate professor of population health sciences and obstetrics & gynecology at the University of Wisconsin, Madison.
Also across the cohort, 15% had prediabetes/diabetes at follow-up. “We need to think about women more generally,” she cautioned. “While we recognize the significant elevated risk of HDP and GDM [for the development of subsequent hypertension and cardiovascular risk], we will miss a lot of women [if we focus only on the history of HDP and GDM.]”
The majority of women found to have hypertension or prediabetes/diabetes at follow-up had experienced neither HDP nor GDM, but a good many of them (47% of those who had hypertension and 47% of those found to have prediabetes/diabetes) had a BMI of 30 or above, Dr. Ehrenthal said at the DPSG-NA meeting.