title: Lean mass deficits, vitamin D status and exercise capacity in children and young adults after Fontan palliation.
abstract: OBJECTIVE
  We sought to evaluate body composition in children and young adults with Fontan physiology. Leg lean mass (LM) deficits correlate with diminished exercise capacity in other populations and may contribute to exercise limitations in this cohort.
  
  
  METHODS
  This cross-sectional study included whole body dual energy X-ray absorptiometry scans in 50 Fontan participants ≥5 years, and measures of peak oxygen consumption (VO2) in 28. Whole body and leg LM (a measure of skeletal muscle) were converted to sex- and race-specific Z-scores, relative to age and stature, based on 992 healthy reference participants.
  
  
  RESULTS
  Median age was 11.5 (range 5.1-33.5) years at 9.3 (1.1-26.7) years from Fontan. Height Z-scores were lower in Fontan compared with reference participants (-0.47±1.08 vs 0.25±0.93, p<0.0001). Body mass index Z-scores were similar (0.15±0.98 vs 0.35±1.02, p=0.18). LM Z-scores were lower in Fontan compared with reference participants (whole body LM -0.33±0.77 vs 0.00±0.74, p=0.003; leg LM -0.89±0.91 vs 0.00±0.89, p<0.0001). LM Z-scores were not associated with age or Fontan characteristics. Leg LM Z-scores were lower in vitamin D deficient versus sufficient Fontan participants (-1.47±0.63 vs -0.71±0.92, p=0.01). Median per cent predicted peak VO2 was 81% (range 13%-113%) and was associated with leg LM Z-scores (r=0.54, p=0.003).
  
  
  CONCLUSIONS
  Following Fontan, children and young adults are shorter than their peers and have significant LM deficits. Skeletal muscle deficits were associated with vitamin D deficiency and reduced exercise capacity. Future studies should examine the progression of these deficits to further understand the contribution of peripheral musculature to Fontan exercise capacity.
authors: Division of Cardiology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA.
authors: Catherine M
authors: CM
authors: Avitabile
authors: Division of Nephrology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA Department of Biostatistics and Epidemiology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA.
authors: Mary B
authors: MB
authors: Leonard
authors: Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA.
authors: Babette S
authors: BS
authors: Zemel
authors: Mid-Hudson Medical Group, Poughkeepsie, New York, USA.
authors: Jill L
authors: JL
authors: Brodsky
authors: Division of Gastroenterology and Nutrition, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA.
authors: Dale
authors: D
authors: Lee
authors: Division of Cardiology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA.
authors: Kathryn
authors: K
authors: Dodds
authors: Division of Cardiology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA.
authors: Christina
authors: C
authors: Hayden-Rush
authors: Division of Cardiology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA.
authors: Kevin K
authors: KK
authors: Whitehead
authors: Division of Cardiology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA.
authors: Elizabeth
authors: E
authors: Goldmuntz
authors: Division of Cardiology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA.
authors: Stephen M
authors: SM
authors: Paridon
authors: Division of Cardiology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA.
authors: Jack
authors: J
authors: Rychik
authors: Division of Cardiology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA.
authors: David J
authors: DJ
authors: Goldberg
mesh_terms: D015502:Absorptiometry, Photon; D000293:Adolescent; D000328:Adult; D001823:Body Composition; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D017079:Exercise Tolerance / Q000502:physiology*; D005260:Female; D005500:Follow-Up Studies; D018729:Fontan Procedure; D006330:Heart Defects, Congenital / Q000601:surgery*; D006801:Humans; D015994:Incidence; D007866:Leg; D008297:Male; D010101:Oxygen Consumption; D011184:Postoperative Period; D011446:Prospective Studies; D013851:Thinness / Q000453:epidemiology / Q000209:etiology*; D013997:Time Factors; D014481:United States / Q000453:epidemiology; D014807:Vitamin D / Q000097:blood*; D055815:Young Adult
chemical_list: D014807:Vitamin D
keywords: CONGENITAL HEART DISEASE