Abstract 16135: Higher Body Mass Index in Early Childhood is Associated With Adult Obesity in Patients With a Fontan Circulation

Abstract

Introduction: Obesity is associated with comorbidities that may be detrimental to single-ventricle patients who have had a Fontan procedure. We assessed the prevalence of obesity in adults with a Fontan circulation and evaluated the hypothesis that higher body mass index (BMI) in early childhood is associated with obesity in adulthood. Methods: Retrospective cohort study of patients with a Fontan circulation aged 18-32 years, seen 2011-2019. Those with an atriopulmonary Fontan or chromosomal abnormality known to affect growth were excluded. Historical height and weight measurements, results of recent cardiac testing, and body mass index (BMI) over time were recorded. Obesity was defined as BMI ≥30 kg/m 2 . The associations between childhood anthropometrics, adult BMI, and most recent cardiac testing were assessed. Results: The cohort included 113 adults with a Fontan circulation (median age 22.7 [IQR 20.2-26.4] years; 44% female). There were no significant differences in age, age at Fontan, Fontan type, or ventricular morphology between obese (n=21, 19%; 52% female) and non-obese (n=92, 81%; 41% female) patients. Compared to non-obese adults, obese patients had higher BMI percentiles at age 2 years (80 th [33-95] vs 43 rd [13-82] percentile, p=0.02), at age 4 years (90 th [73-93] vs 57 th [22-81] percentile, p=0.002), and at the time of the Fontan procedure (85 th [51-98] vs 20 th [5-57] percentile, p=0.002). Being overweight at time of Fontan (BMI percentile >85%) strongly predicted later obesity (OR=18.3, 95% CI 3.7-90.3, p<0.001). Obese adults had lower peak VO 2 (19.1±5.2 vs 25.5±6.6 mL/kg/min, p<0.001,) a trend to a lower % predicted VO 2 (59±13 vs 65±14% predicted, p=0.06), higher systolic blood pressure (121±17 vs 112±12 mmHg, p=0.007) and higher ventricular end-diastolic pressure (11±4 vs 9±3 mmHg, p= 0.03). Adult BMI weakly correlated with ventricular end-diastolic pressure (r=0.24, p=0.048). Conclusions: Higher BMI in early childhood is associated with obesity in adults with a Fontan circulation. Adult obesity is associated with worse exercise capacity, higher blood pressure, and higher ventricular end-diastolic pressure. Weight interventions in children with a Fontan circulation may help prevent later obesity and its adverse consequences.