This Article Full Text Full Text (PDF) Submit a related Letter to the Editor Purchase Article View Shopping Cart Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Copyright Permission Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Bakalov, V. K. Articles by Bondy, C. A. Search for Related Content PubMed PubMed Citation Articles by Bakalov, V. K. Articles by Bondy, C. A.

Selective Reduction in Cortical Bone Mineral Density in Turner Syndrome Independent of Ovarian Hormone Deficiency

Developmental Endocrinology Branch (V.K.B., L.A., J.B., L.H., L.M.N., C.A.B.) and Division of Epidemiology, Statistics, and Prevention Research (J.T.), National Institute of Child Health and Human Development, and Warren G. Magnuson Clinical Center Radiology Department (J.C.R., S.H.), National Institutes of Health, Bethesda, Maryland 20892

Address all correspondence and requests for reprints to: Vladimir K. Bakalov, M.D., 10 Center Drive, Building 10/10N262, National Institutes of Health, Bethesda, Maryland 20892. E-mail: bakalov{at}mail.nih.gov.

Women with Turner syndrome (TS) are at risk for osteoporosis from ovarian failure and possibly from haploinsufficiency for bone-related X-chromosome genes. To establish whether cortical or trabecular bone is predominantly affected, and to control for the ovarian failure, we studied forearm bone mineral density (BMD) in 41 women with TS ages 18–45 yr and in 35 age-matched women with karyotypically normal premature ovarian failure (POF). We measured BMD at the 1/3 distal radius (D-Rad_1/3; predominantly cortical bone) and at the ultradistal radius (UD-Rad; predominantly trabecular bone) by dual x-ray absorptiometry.

Women with TS had lower cortical BMD compared with POF (D-Rad_1/3 Z-score = -1.5 ± 0.8 for TS and 0.08 ± 0.7 for POF; P < 0.0001). In contrast, the primarily trabecular UD-Rad BMD was normal in TS and not significantly different from POF (Z-score = -0.62 ± 1.1 for TS and -0.34 ± 1.0 for POF; P = 0.26). The difference in cortical BMD remained after adjustment for height, age of puberty, lifetime estrogen exposure, and serum 25-hydroxyvitamin D (P = 0.0013). Cortical BMD was independent of serum IGF-I and -II, PTH, and testosterone in TS.

We conclude that there is a selective deficiency in forearm cortical bone in TS that appears independent of ovarian hormone exposure and is probably related to X-chromosome gene(s) haploinsufficiency.

Abbreviations: BMAD, Bone mineral apparent density; BMD, bone mineral density; D-Rad_1/3, 1/3 distal radius; DXA, dual x-ray absorptiometry; HRT, hormone replacement therapy; POF, premature ovarian failure; TS, Turner syndrome; UD-Rad, ultradistal radius.

This article has been cited by other articles:

				C. A. Bondy and for The Turner Syndrome Consensus Study Group Care of Girls and Women with Turner Syndrome: A Guideline of the Turner Syndrome Study Group J. Clin. Endocrinol. Metab., January 1, 2007; 92(1): 10 - 25. [Abstract] [Full Text] [PDF]

				M. Ari, V. K. Bakalov, S. Hill, and C. A. Bondy The Effects of Growth Hormone Treatment on Bone Mineral Density and Body Composition in Girls with Turner Syndrome J. Clin. Endocrinol. Metab., November 1, 2006; 91(11): 4302 - 4305. [Abstract] [Full Text] [PDF]

				P. J. Schmidt, G. M. P. Cardoso, J. L. Ross, N. Haq, D. R. Rubinow, and C. A. Bondy Shyness, Social Anxiety, and Impaired Self-esteem in Turner Syndrome and Premature Ovarian Failure JAMA, March 22, 2006; 295(12): 1374 - 1376. [Full Text] [PDF]

				V. K. Bakalov, P. L. Van, J. Baron, J. C. Reynolds, and C. A. Bondy Growth Hormone Therapy and Bone Mineral Density in Turner Syndrome J. Clin. Endocrinol. Metab., October 1, 2004; 89(10): 4886 - 4889. [Abstract] [Full Text] [PDF]