70 - Longitudinal Assessment of Blood Pressure at Ages 3-6 in Growth Restricted Fetuses.

Poster Number: 70
Publication Number: 70.2070

Background: Fetal growth restriction (FGR), defined as a fetus with an estimated fetal weight or abdominal circumference less than the national 10th percentiles on any antepartum ultrasound, is a known risk factor for developing hypertension later in life, likely due to genetic reprogramming in utero. In the US, the prevalence of childhood hypertension ranges from 2.2%-3.9% and is increasing.

Objective: To determine whether FGR children display a trajectory of diastolic (DBP) and systolic (SBP) blood pressures from ages 3-6 that differs from their normative peers.

Design/Methods: A database for FGR was used to conduct this retrospective cohort study. The study population included 155 FGR babies born between 2015 and 2016. BMI, DBP, and SBP were measured at yearly intervals from ages 3 to 6. Using reference data from the CDC, we compared DBP and SBP values for each FGR child to age- and sex-matched 50th percentile DBP/SBP values measured at the sex-specific 50th height percentiles. Model parameters were estimated using full information maximum likelihood to account for missing values and first-order autoregressive residual covariance structure with empirically estimated parameters. Additionally, the total number of FGR children who reached stage I and stage II hypertension were calculated.

Results: Our longitudinal models explained approximately 58.1% of the longitudinal variance in DBP (p=7.5x10-60) and 24.9% of the variance in SBP (p=5.9x10-19). The mean DBP of FGR babies was 9.1 points higher at age 3 (p=6.7x10-20) and decreased by 1.5 points on average each year (p=1.7x10-3). Conversely, the mean SBP of FGR babies at age 3 did not differ from the matched reference (p=0.739) and showed no evidence of change from ages 3-6 (p=0.932). However, female FGR babies had SBP values which were on average 4.6 points higher than their male FGR counterparts (p=3.7x10-3), who did not marginally differ from the reference at any age (p=0.710 ) (Figure 1). 34/151 (22.5%) of FGR children reached Stage I hypertension but not Stage II, and 6/151 (4.0%) reached Stage II from ages 3-6.

Conclusion(s): Our results show higher average DBP and different trajectories of change from ages 3-6 between FGR children and their matched references. We found no evidence that SBP trajectories differed between FGR children and reference values, but strong evidence that FGR females have greater mean SBP from ages 3-6 than their male counterparts. Finally, the prevalence of hypertension in our sample of FGR children is higher than the national range.