LV Mass in Children With Extremely Low Birth Weight Is Lower But More Sensitive to Increased Blood Pressure

BACKGROUND: 

Epidemiological evidence suggests higher rates of heart failure in adults born at an extremely low birth weight (ELBW). Reports on the echocardiographic phenotype in this population are inconsistent and do not consider the effect of modifiable contributors such as blood pressure. 

METHODS: 

This study reports on the echocardiographic findings of the PREMATurity as predictor of children's Cardiovascular-renal Health (PREMATCH) study, a prospective case-control study evaluating renal and cardiovascular outcomes in children with ELBW in comparison to term-born controls. Left ventricular (LV) mass was the primary outcome. Data were analyzed with multivariable-adjusted regression models considering anthropometric variables and systolic blood pressure as covariates. 

RESULTS: 

Eighty cases (median age, 10.8 years) and 72 controls (median age, 11.4 years) were included. Multivariable-adjusted analyses revealed that the adjusted difference in LV mass in cases versus controls was -8.49 g (CI, -13.78 to -3.20; P=0.002). Sex, height, weight, and body fat percentage were significant covariates. There was a positive interaction between ELBW status and systolic blood pressure (Pinteraction=0.039). There was a -6.47 g (CI, -11.7 to 1.28; P=0.016) difference in LV mass between normotensive cases and controls, while the difference disappeared between subjects with increased blood pressure or hypertension. 

CONCLUSIONS: 

ELBW children exhibit lower LV mass during childhood in comparison with term-born controls. However, elevations in systolic blood pressure are associated with a steeper increase in LV mass in cases than in controls. Our findings question whether cutoffs for the general population are adequate to evaluate and manage hypertension and LV hypertrophy in children with ELBW.