Osteoporosis International

, Volume 17, Issue 1, pp 77–84

Changes in bone mineral density, body composition and biochemical markers of bone turnover during weight gain in adolescents with severe anorexia nervosa: a 1-year prospective study

  • J. E. Compston
  • C. McConachie
  • C. Stott
  • R. A. Hannon
  • S. Kaptoge
  • I. Debiram
  • S. Love
  • A. Jaffa
Original Article

DOI: 10.1007/s00198-005-1904-6

Cite this article as:
Compston, J.E., McConachie, C., Stott, C. et al. Osteoporos Int (2006) 17: 77. doi:10.1007/s00198-005-1904-6

Abstract

Osteoporosis is a serious complication of anorexia nervosa and in affected adolescents may result in a permanent deficit in bone mass. The pathophysiology of this bone disease has not been clearly defined. In this prospective study of 26 young women with anorexia nervosa aged 13–20 years (mean 16.5) we have measured changes in bone mineral density, total body composition and biochemical indices of bone turnover over 1 year. Over this period there was a mean weight gain of 10 kg and significant height gain with baseline and final values for body mass index of 14.2±1.7 and 17.6±2.3 kg/m2 (P<0.001). However, no significant changes were seen in bone mineral density in the spine or proximal femur during the study; total body bone mineral content was significantly higher than baseline at 3 months and 12 months (P=0.001 and P<0.0001), but total body bone mineral density at 3 months was significantly lower than baseline (P=0.003). Serum osteocalcin and bone-specific alkaline phosphatase values increased significantly and remained higher than baseline at all time points whereas urinary NTX/creatinine excretion showed a non-significant increase over the first 6 months of the study, but at 12 months, the mean value was significantly lower than baseline. Mean serum 25-hydroxyvitamin D levels showed a significant decrease at 6 months (P<0.05), but returned towards baseline thereafter. There was a significant increase in serum parathyroid hormone levels at all time points compared to baseline, these occurring within the normal range. These results indicate that although weight gain in young anorexics is associated with linear growth, bone mineral density does not increase. Whether this deficit can be corrected subsequently requires longer-term prospective studies.

Keywords

Anorexia nervosaBody compositionBone mineral densityOsteoporosis

Copyright information

© International Osteoporosis Foundation and National Osteoporosis Foundation 2005

Authors and Affiliations

  • J. E. Compston
    • 1
    • 9
  • C. McConachie
    • 2
  • C. Stott
    • 3
  • R. A. Hannon
    • 4
  • S. Kaptoge
    • 5
  • I. Debiram
    • 6
  • S. Love
    • 7
  • A. Jaffa
    • 8
  1. 1.Department of MedicineUniversity of Cambridge School of Clinical MedicineCambridgeUK
  2. 2.The Croft Children’s UnitCambridgeUK
  3. 3.Department of Developmental PsychiatryDouglas HouseCambridgeUK
  4. 4.Academic Unit of Bone MetabolismUniversity of SheffieldSheffieldUK
  5. 5.Bone Research GroupStrangeways Research LaboratoryCambridgeUK
  6. 6.Department of MedicineAddenbrooke’s HospitalCambridgeUK
  7. 7.Metabolic Bone UnitAddenbrooke’s HospitalCambridgeUK
  8. 8.The Phoenix CentreCambridgeUK
  9. 9.Department of MedicineAddenbrooke’s HospitalCambridgeUK