Deficits in the Functional Muscle-Bone Unit in Youths with Fontan Physiology.

TitleDeficits in the Functional Muscle-Bone Unit in Youths with Fontan Physiology.
Publication TypeJournal Article
Year of Publication2021
AuthorsVaikunth SS, Leonard MB, Whitehead KK, Goldberg DJ, Rychik J, Zemel BS, Avitabile CM
JournalJ Pediatr
Volume238
Pagination202-207
Date Published2021 11
ISSN1097-6833
KeywordsAbsorptiometry, Photon, Adolescent, Bone Density, Child, Child, Preschool, Cross-Sectional Studies, Female, Fontan Procedure, Heart Defects, Congenital, Humans, Male, Muscle, Skeletal
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 (R = 0.40; P < .001), lumbar spine (R = 0.16; P = .005), total hip (R = 0.32; P < .001), femoral neck (R = 0.47; P < .001), and ultradistal radius (R = 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.

DOI10.1016/j.jpeds.2021.06.068
Alternate JournalJ Pediatr
PubMed ID34214589
PubMed Central IDPMC8634795
Grant ListK23 HL089647 / HL / NHLBI NIH HHS / United States
R01 HL098252 / HL / NHLBI NIH HHS / United States
K23 HL150337 / HL / NHLBI NIH HHS / United States
T32 HL007915 / HL / NHLBI NIH HHS / United States
UL1 TR000003 / TR / NCATS NIH HHS / United States
K24 DK076808 / DK / NIDDK NIH HHS / United States
UL1 RR024134 / RR / NCRR NIH HHS / United States