Assistant Professor/Pediatric Renal Dietitian University of Kentucky College of Medicine University of Kentucky Healthcare Lexington, Kentucky, United States
Background: Left ventricular hypertrophy (LVH) is a predictor of hypertension (HTN) related organ dysfunction and a risk factor for cardiovascular disease. Increased BMI is associated with LVH in youth with HTN, but the interactions among pediatric body mass, blood pressure (BP), and LV mass are not well defined. Objective: Investigate relationships among pediatric BMI and BMI%, 24hr blood pressure status, and LV mass in a cohort of children ages 6-18 yrs referred to our pediatric nephrology division for BP evaluation. The goal was to better define drivers of LV mass and LVH in children with obesity. Design/Methods: With the approval of our IRB, we conducted a retrospective chart review of all patients ages 6-18 years who underwent 24-hr ambulatory BP monitoring via the pediatric nephrology clinic at Kentucky Children’s Hospital from August 2012-December 2022. We excluded those with conditions that could affect BP, such as chronic kidney disease and congenital heart disease. Obesity was defined by BMI and weight-for-length percentiles. LV mass was assessed by standard echocardiography. We compared LV mass index and BP measures among three groups (obese-normotensive, non obese-hypertensive, and obese-hypertensive). Statistical tests included Pearson’s chi-square, Fisher’s exact test, and multivariable logistic modeling using a backwards elimination variables selection criteria with α=0.05. Results: Of the 688 participants, 64% (n=438) were male, 77% (n=524) were obese, and 68% (n=462) completed echocardiograms. LVH was present in 184 patients, with significant differences noted for obesity, male sex, sleep disordered breathing, 24-hr systolic BP, uric acid, TSH, T4, HDL and LDL cholesterol, vitamin D, and HgbA1c compared to patients without LVH. No differences were found for BP severity or nocturnal dipping. Multivariable logistic modeling demonstrated sex, BMI percentile, and uric acid as significant in explaining the variation of LVH in the presence of other variables, whereas hemodynamic variables were not correlated with LVH.
Conclusion(s): These findings confirm the high incidence of LVH in children with obesity and further suggest that increased LV mass childhood may be more linked to and/or driven by adiposity than cardiac mechanical work or afterload. Further investigation of fat-derived factors involved in LV mass during childhood appear warranted.
