Bone metabolism in adolescent boys with anorexia nervosa.

Abstract

BACKGROUND:

Anorexia nervosa (AN) is a condition of severe undernutrition associated with low bone mineral density (BMD) in adolescent females with this disorder. Although primarily a disease in females, AN is increasingly being recognized in males. However, there are few or no data regarding BMD, bone turnover markers or their predictors in adolescent AN boys.

HYPOTHESES:

We hypothesized that BMD would be low in adolescent boys with AN compared with controls associated with a decrease in bone turnover markers, and that the gonadal steroids, testosterone and estradiol, and levels of IGF-I and the appetite regulatory hormones leptin, ghrelin, and peptide YY would predict BMD and bone turnover markers.

METHODS:

We assessed BMD using dual-energy x-ray absorptiometry and measured fasting testosterone, estradiol, IGF-I, leptin, ghrelin, and peptide YY and a bone formation (aminoterminal propeptide of type 1 procollagen) and bone resorption (N-telopeptide of type 1 collagen) marker in 17 AN boys and 17 controls 12-19 yr old.

RESULTS:

Boys with AN had lower BMD and corresponding Z-scores at the spine, hip, femoral neck, trochanter, intertrochanteric region, and whole body, compared with controls. Height-adjusted measures (lumbar bone mineral apparent density and whole body bone mineral content/height) were also lower. Bone formation and resorption markers were reduced in AN, indicating decreased bone turnover. Testosterone and lean mass predicted BMD. IGF-I was an important predictor of bone turnover markers.

CONCLUSION:

AN boys have low BMD at multiple sites associated with decreased bone turnover markers at a time when bone mass accrual is critical for attainment of peak bone mass.

• Authors: Madhusmita Misra, Debra K Katzman, Jennalee Cord, Stephanie J Manning, Nara Mendes, David B Herzog, Karen K Miller, Anne Klibanski
• Journal: The Journal of clinical endocrinology and metabolism (J Clin Endocrinol Metab) Vol. 93 Issue 8 Pg. 3029-36 (Aug 2008) ISSN: 0021-972X [Print] United States
• PMID: 18544623 (Publication Type: Journal Article, Research Support, N.I.H., Extramural)

Chemical References

• Peptide Fragments
• Procollagen
• procollagen Type I N-terminal peptide
• Peptide YY
• Insulin-Like Growth Factor I

Topics

• Absorptiometry, Photon
• Adolescent
• Anorexia Nervosa (metabolism)
• Body Composition
• Body Mass Index
• Bone Density
• Bone and Bones (metabolism)
• Humans
• Insulin-Like Growth Factor I (analysis)
• Male
• Peptide Fragments (blood)
• Peptide YY (blood)
• Procollagen (blood)