The association of gestational age and birthweight with blood pressure, cardiac structure, and function in 4 years old: a prospective birth cohort study

Background Current evidence relating birthweight and gestational age to cardiovascular risk is conflicting. Whether these factors have independent or interactive impacts on cardiovascular parameters during early childhood remains unclear. The goal of this study was to explore whether there were any independent and interactive effects of gestational age and birthweight on blood pressure, left ventricle (LV) structure, and function in 4 years old. Methods This study included 1194 children in the Shanghai Birth Cohort from 2013 to 2016. Information about the mothers and children was recorded at time of birth using a questionnaire. Follow-up measurements, including anthropometric, blood pressure, and echocardiography, were taken between 2018 and 2021, when the children were 4 years old. Multiple linear or logistic regressions and restricted cubic spline were used to explore the association of birthweight and gestational age with cardiovascular measurements. Results Gestational age had a significant negative correlation with both systolic blood pressure [ β = − 0.41, 95% CI: (− 0.76, − 0.07)] and mean arterial pressure [ β = − 0.36, 95%CI: (− 0.66, − 0.07)]. The risk of prehypertension decreased with increased gestational age [OR = 0.54, 95% CI: (0.32, 0.93)]. The relationship between birthweight with blood pressure was U-shape ( P for non-linear < 0.001). The wall thickness, volume, mass, and cardiac output of LV increased with birthweight, though the ejection fraction [ β = − 1.02, 95% CI: (− 1.76, − 0.27)] and shorten fraction [ β = 0.72, 95% CI: (− 1.31, − 0.14)] decreased with birthweight. The risk of LV hypertrophy was not associated with birthweight [OR = 1.59, 95% CI: (0.68, 3.73)]. Conclusions In this study, we found different associations of birthweight and gestational age with cardiovascular measurements in the offspring at 4 years old. Gestational age influenced blood pressure independent of birthweight. Heart size and function at 4 years old was influenced mostly by birthweight and not by gestational age.