The intergenerational metabolic-cardiovascular life course: maternal body mass index (BMI), offspring BMI, and blood pressure of adolescents born extremely preterm.

Background: The aim of this study was to evaluate associations between pre-pregnancy maternal obesity and adolescent blood pressures (BPs) among children born extremely preterm.

Methods: This longitudinal observational cohort study included participants in the multicenter Extremely Low Gestational Age Newborn (ELGAN) study, born before 28 weeks of gestation, recruited at birth between 2002 and 2004, and followed prospectively through late adolescence. Between 2015 and 2022, three oscillometric BPs were obtained from participants (mean age 17.8 years). We used linear regression modeling to evaluate the association between maternal self-reported pre-pregnancy body mass index (BMI) and offspring adolescent systolic BP (SBP). In secondary analyses, we evaluated the association between maternal pre-pregnancy and offspring preadolescent (10-year-old) BMI and between offspring preadolescent BMI and adolescent SBP.

Results: The 100 (24%) participants born to a mother with a history of pre-pregnancy obesity (BMI ≥ 30) had a greater mean SBP of 120.5 (± 14.3) mmHg compared to the 324 (76%) of adolescents born to mothers without pre-pregnancy obesity (SBP 115.6 (± 12.0) mmHg). Pre-pregnancy obesity was associated with higher offspring BMI (aβ 10.8, 95% CI 2.3, 19.2), and higher offspring BMI was associated with higher adolescent SBP (aβ 0.12, 95% CI 0.09,0.16).

Conclusions: For ELGANs, higher maternal pre-pregnancy BMI was associated with higher adolescent SBP. Findings from secondary analyses suggest potential mediation through preadolescent BMI. Future research directions include multi-level interventions to reduce maternal pre-pregnancy obesity, followed by offspring obesity prevention interventions as a way of reducing intergenerational cardiovascular disease in high-risk infants born extremely preterm.