Obesity may portend CV risks in pregnancy

In young pregnant women, obesity was associated with parameters that may bring on preeclampsia and other CV complications, researchers reported at the American Heart Association’s Basic Cardiovascular Sciences Scientific Sessions.

Perspective from Robert H. Eckel, MD

“The cardiovascular system of women undergoes profound changes during pregnancy, which return to pre-pregnancy levels 3 to 6 months after delivery. The main goal of this ongoing study is to follow women through pregnancy to detect whether there are differences in how an obese woman’s cardiovascular system changes during pregnancy that might explain their predisposition to preeclampsia and other cardiovascular complications,” Katherine Shreyder, MD, PhD, a medical resident in the department of internal medicine at Texas Tech University Health Sciences Center at Permian Basin in Odessa, Texas, said in a press release.

Shreyder and colleagues analyzed 11 obese women (mean age, 30 years; mean BMI, 33.6 kg/m²) and 13 normal-weight or overweight women (mean age, 26 years; mean BMI, 25.5 kg/m²) to determine heart and chemical changes during their first pregnancies.

The researchers correlated echocardiography changes to messenger RNA and the dynamics of biomarkers including leptin, tumor necrosis factor-alpha, B-type natriuretic peptide, pentraxin-3 and interleukin-6. In the presentation, Shreyder presented results related to echocardiography findings, leptin and tumor necrosis factor-alpha.

According to an abstract provided by the AHA, compared with the normal-weight/overweight group, the obese group had higher systolic BP (125 mm Hg vs. 109 mm Hg; P < .05) and higher diastolic BP (79.7 mm Hg vs. 68.8 mm Hg; P < .05).

In addition, in the obese group, left ventricular mass was higher (122.6 g vs. 97.4 g; P < .05), LV ejection fraction was lower (71% vs. 73.7%; P < .05) and the ratio of the early to late ventricular filling velocities (E/A ratio) was lower (1.5 vs. 1.83; P < .05) compared with the normal-weight/overweight group, Shreyder and colleagues found.

Leptin levels were higher in the obese group (73.1 ng/mL vs. 48.9 ng/mL; P < .05) and tumor necrosis factor-alpha levels were higher in the obese group, but the difference did not reach statistical significance, according to the researchers.

“It seems that the obese patients will be more likely to deteriorate during pregnancy, because we started to observe higher BP (although still in the normal range), an increase in LV mass, and diminished pumping strength and relaxation,” Shreyder said in the release. “Echocardiography might turn out to be a useful screening tool in obese pregnant women if further research establishes a definite connection between changes seen on echocardiography early in pregnancy and the risk of preeclampsia.” – by Erik Swain

Reference:

Shreyder K, et al. Poster Presentation 493. Presented at: American Heart Association’s Basic Cardiovascular Sciences Scientific Sessions; July 30-Aug. 2, 2018; San Antonio.

Disclosure: Shreyder reports no relevant financial disclosures.

Perspective

Robert H. Eckel, MD

The findings are of interest, but there is a lot of hypothesis testing yet to come. The results so far have not related to preeclampsia or eclampsia. The number of subjects is small and there is no control group of non-pregnant women who are similarly obese or have normal BMI. Despite that these data might highlight risks for pregnant women, it’s not clear that the differences in CVD risk are unique to pregnancy. Moreover, most of the metabolic stress of pregnancy does not occur in the first trimester, but in the late second and third trimesters. Thus, we need to see measurements carried out throughout pregnancy. We also need to know a lot more, including obtaining similar data from a control group of nonpregnant women matched for age and obesity or normal weight, a larger sample size and longitudinal measurements covering the later stages of pregnancy when stress on BP and risk for preeclampsia increases dramatically. The door has been cracked, but needs to be opened much more widely before we have a complete understanding of this issue.

Robert H. Eckel, MD

Professor of Medicine

Division of Endocrinology, Metabolism and Diabetes

Division of Cardiology

Professor of Physiology and Biophysics

Charles A. Boettcher II Chair in Atherosclerosis

University of Colorado Anschutz Medical Campus

Past President, American Heart Association

Disclosures: Eckel reports no relevant financial disclosures.