Prevalence of Overweight and Obesity in Pediatric Congenital Heart Disease: Associations with Hypertension and Echocardiographic Findings

Background: The impact of overweight and obesity on blood pressure and cardiac remodelling in pediatric congenital heart disease (CHD) remains incompletely defined, particularly across different ventricular physiologies and cardiac anatomies. Aim: To assess the association of overweight and obesity with arterial blood pressure and cardiac remodelling in pediatric and young adult patients with CHD, according to ventricular physiology and cardiac anatomy. Methods: In this observational study, pediatric CHD patients undergoing clinical and echocardiographic evaluation were classified by weight status and ventricular physiology, with additional stratification by cardiac anatomy. Associations between body mass index (BMI), arterial hypertension, and echocardiographic parameters were analyzed. Results: A total of 451 patients were included (mean age 13.1 ± 3.9 years; 74 univentricular, 377 biventricular). Overall, 16% were overweight and 7% obese. Hypertension was present in 16% and increased across BMI categories (14%, 26%, and 50%). BMI was associated with blood pressure category (p < 0.001), higher systolic blood pressure (p < 0.001), and increased left ventricular (LV) mass (p = 0.007), interventricular septal thickness (p < 0.001), and posterior wall thickness (p < 0.001), without evidence of systolic dysfunction. In adjusted models, overweight/obesity remained associated with worse blood pressure classification, both as a three-category outcome (OR 2.1, 95% CI 1.4–3.2; p < 0.001) and as a binary outcome (OR 2.3, 95% CI 1.5–3.7; p < 0.001), as well as with higher systolic blood pressure (β = 5.1 mmHg, 95% CI 2.4–7.8; p < 0.001), left ventricular mass index (LVMI) (β = 10.0, 95% CI 4.3–15.8; p < 0.001), interventricular septal thickness at end-diastole (IVSd) (p < 0.001), and left ventricular posterior wall in diastole (LVPWd) (p < 0.001), but not with diastolic blood pressure or systolic function. No significant associations were observed in univentricular patients, whereas in biventricular circulation higher BMI was consistently associated with worse blood pressure and remodeling, without systolic dysfunction. Conclusions: Excess body weight is independently associated with adverse blood pressure status and early LV structural remodelling in pediatric and young adult patients with CHD, despite preserved systolic function. These findings support early cardiovascular risk surveillance and preventive strategies targeting overweight and obesity in CHD care.