Weight Gain and Blood Pressure in Toddlers Born Very Preterm

Preterm birth is a risk factor for elevated blood pressure in childhood and the development of hypertension and cardiometabolic disease in adulthood; however, mechanisms for the development of both are poorly understood. Rapid weight gain early in childhood may serve as a driver directly and indirectly through cortisol levels found to be elevated in early childhood in individuals born preterm.

The objective of this pilot study was to examine the effect sizes of the relationships between weight gain and blood pressure in toddlers born very preterm. A secondary aim was to note any mediating effect of cortisol on the relationships between weight gain and blood pressure.

A cross-sectional design with a convenience sample of 36 toddlers who were born very preterm was used to examine the relationships between postnatal weight gain, cortisol, and blood pressure at follow-up.

Many of the participants experienced rapid weight gain in the first 12 months of life. Mean systolic and diastolic readings were 94 and 56.6, respectively. Diastolic blood pressure readings were obtained from 23 participants, and the majority were elevated. Weight gain was associated with diastolic blood pressure with a medium effect size. A mediating role with cortisol was not supported.

Although findings need to be validated in a larger sample, the blood pressure elevations in this sample were alarming. If readings continue to amplify as these children age, the fact that elevations are already present during the toddler period could indicate more significant cardiovascular disease in adulthood for this population. Rapid weight gain in early life may be a driver for elevated blood pressure even during early childhood in individuals born preterm.