Sumeet S Vaikunth1, Mary B Leonard2, Kevin K Whitehead3, David J Goldberg3, Jack Rychik3, Babette S Zemel4, Catherine M Avitabile5. 1. Division of Cardiovascular Medicine, Stanford University School of Medicine, Palo Alto, CA. 2. Department of Medicine, Stanford University School of Medicine, Palo Alto, CA; Department of Pediatrics, Stanford University School of Medicine, Palo Alto, CA. 3. Division of Cardiology, The Children's Hospital of Philadelphia, Philadelphia, PA; Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA. 4. Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA; Division of Gastroenterology, Hepatology and Nutrition, The Children's Hospital of Philadelphia, Philadelphia, PA. 5. Division of Cardiology, The Children's Hospital of Philadelphia, Philadelphia, PA; Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA. Electronic address: avitabilec@email.chop.edu.
Abstract
OBJECTIVE: To determine whether dual energy X-ray absorptiometry (DXA), a clinically available tool, mirrors the magnitude of deficits in trabecular and cortical bone mineral density (BMD) demonstrated on peripheral quantitative computed tomography in youth with Fontan physiology. STUDY DESIGN: We aimed to describe DXA-derived BMD at multiple sites and to investigate the relationship between BMD and leg lean mass, a surrogate for skeletal muscle loading. Subjects with Fontan (n = 46; aged 5-20 years) underwent DXA in a cross-sectional study of growth and bone and muscle health as described previously. Data from the Bone Mineral Density in Childhood Study were used to calculate age-, sex-, and race-specific BMD z-scores of the whole body, lumbar spine, hip, femoral neck, distal one-third radius, ultradistal radius, and leg lean mass z-score (LLMZ). RESULTS: Fontan BMD z-scores were significantly lower than reference at all sites-whole body, -0.34 ± 0.85 (P = .01); spine, -0.41 ± 0.96 (P = .008); hip, -0.75 ± 1.1 (P < .001); femoral neck, -0.73 ± 1.0 (P < .001); distal one-third radius, -0.87 ± 1.1 (P < .001); and ultradistal radius. -0.92 ± 1.03 (P < .001)-as was LLMZ (-0.93 ± 1.1; P < .001). Lower LLMZ was associated with lower BMD of the whole body (R2 = 0.40; P < .001), lumbar spine (R2 = 0.16; P = .005), total hip (R2 = 0.32; P < .001), femoral neck (R2 = 0.47; P < .001), and ultradistal radius (R2 = 0.35; P < .001). CONCLUSIONS: Patients with Fontan have marked deficits in both cortical (hip, distal one-third radius) and trabecular (lumbar spine, femoral neck, ultradistal radius) BMD. Lower LLMZ is associated with lower BMD and may reflect inadequate skeletal muscle loading. Interventions to increase muscle mass may improve bone accrual.
OBJECTIVE: To determine whether dual energy X-ray absorptiometry (DXA), a clinically available tool, mirrors the magnitude of deficits in trabecular and cortical bone mineral density (BMD) demonstrated on peripheral quantitative computed tomography in youth with Fontan physiology. STUDY DESIGN: We aimed to describe DXA-derived BMD at multiple sites and to investigate the relationship between BMD and leg lean mass, a surrogate for skeletal muscle loading. Subjects with Fontan (n = 46; aged 5-20 years) underwent DXA in a cross-sectional study of growth and bone and muscle health as described previously. Data from the Bone Mineral Density in Childhood Study were used to calculate age-, sex-, and race-specific BMD z-scores of the whole body, lumbar spine, hip, femoral neck, distal one-third radius, ultradistal radius, and leg lean mass z-score (LLMZ). RESULTS: Fontan BMD z-scores were significantly lower than reference at all sites-whole body, -0.34 ± 0.85 (P = .01); spine, -0.41 ± 0.96 (P = .008); hip, -0.75 ± 1.1 (P < .001); femoral neck, -0.73 ± 1.0 (P < .001); distal one-third radius, -0.87 ± 1.1 (P < .001); and ultradistal radius. -0.92 ± 1.03 (P < .001)-as was LLMZ (-0.93 ± 1.1; P < .001). Lower LLMZ was associated with lower BMD of the whole body (R2 = 0.40; P < .001), lumbar spine (R2 = 0.16; P = .005), total hip (R2 = 0.32; P < .001), femoral neck (R2 = 0.47; P < .001), and ultradistal radius (R2 = 0.35; P < .001). CONCLUSIONS:Patients with Fontan have marked deficits in both cortical (hip, distal one-third radius) and trabecular (lumbar spine, femoral neck, ultradistal radius) BMD. Lower LLMZ is associated with lower BMD and may reflect inadequate skeletal muscle loading. Interventions to increase muscle mass may improve bone accrual.
Authors: Jack Rychik; David J Goldberg; Elizabeth Rand; Edna E Mancilla; Jennifer Heimall; Nicholas Seivert; Danielle Campbell; Shannon O'Malley; Kathryn M Dodds Journal: Pediatr Cardiol Date: 2022-05-23 Impact factor: 1.838