Children born from assisted reproductive technologies such as in vitro fertilization and intracytoplasmic sperm injection may be at risk of developing arterial hypertension due to premature vascular aging, according to a study published in the Journal of the American College of Cardiology.
In a previous study, Emrush Rexhaj, MD, director of arterial hypertension and altitude medicine at Inselspital, University Hospital, Bern, Switzerland, and his colleagues assessed vascular function in participants who were born with assisted reproductive technology (ART) such as in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI); the investigators found vascular dysfunction in this patient population not “related to parental factors but to the ART procedure itself,” they said.
Dr. Rexhaj and his colleagues then reassessed vascular function in 54 participants (mean age 16.5 years old) who returned from the previous study 5 years after the initial assessment and compared the results with 43 matched patients in a control group (mean age, 17.4 years). There were no significant differences regarding body mass index, lipid, creatinine, electrolyte plasma concentrations, high-sensitive C-reactive protein, birth weight, and gestational age between children in either group, as well as no significant differences in maternal BMI, cardiovascular risk profile, and smoking status.
The investigators – with Théo A. Meister, MD, also of the university, as a joint lead author with Dr. Rexhaj – performed blinded endothelium-dependent and endothelium-independent vasodilation of the brachial artery in a supine position at room temperature and after 15 minutes of rest. They also measured carotid intima-media thickness (IMT), large artery stiffness, 24-hour ambulatory blood pressure monitoring, and short-term blood pressure variability.
“It only took five years for differences in arterial blood pressure to show,” Dr. Rexhaj stated in a press release. “This is a rapidly growing population and apparently healthy children are showing serious signs of concern for early cardiovascular risk, especially when it comes to arterial hypertension.”
Specifically, there was an approximately 25% reduction in flow-mediated dilation in the ART group (7%) compared with the control group (9%), which the investigators attributed to endothelial dysfunction (P less than .001). In ART patients, carotid IMT (463 mm) and carotid pulse-wave velocity (7.7 m/s) was significantly increased, compared with carotid IMT (435 mm; P less than .01) and pulse-wave velocity (7.2 m/s; P equals .033) in the control group.
With regard to arterial hypertension, 24-hour systolic blood pressure in the ART group (120 mm Hg) was “markedly” higher than in the control group (116 mm Hg; P equals .02); 24-hour diastolic blood pressure was also significantly higher in the ART group (71 mm Hg) compared with the control group (69 mm Hg; P equals .03). Investigators noted 8 of the 52 patients (15%) in the ART group met clinical criteria for arterial hypertension according to ambulatory blood pressure monitoring, compared with 1 of the 40 patients (2%) in the control group.
“The increased prevalence of arterial hypertension in ART participants is what is most concerning,” Dr. Rexhaj stated in the release. “There is growing evidence that ART alters the blood vessels in children, but the long-term consequences were not known. We now know that this places ART children at a six times higher rate of hypertension than children conceived naturally.”
The investigators cited as a limitation the fact that they studied only children born from singleton births recruited from a single center, which may have a lower cardiovascular risk profile than other patient populations.
This study was supported by the Swiss National Science Foundation, the Placide Nicod Foundation, the Swiss Society of Hypertension, the Swiss Society of Cardiology and Mach-Gaensslen Stiftung (Schweiz). The authors reported no conflicts of interest.
SOURCE: Meister TA et al. J Am Coll Cardiol. 2018 Sep 3. doi: 10.1016/j.jacc.2018.06.060.