title: Relationship between subclinical thyroid dysfunction and femoral neck bone mineral density in women.
abstract: BACKGROUND
  Osteoporosis associated with thyroid dysfunction has been traditionally viewed as a secondary consequence of altered thyroid function, but there was recently a report about the direct effects of thyroid-stimulating hormone (TSH) on bone remodeling, which was mediated via the TSH receptor found on osteoblast and osteoclast precursor cells. Endogenous subclinical thyroid dysfunction seems to be an appropriate model to examine the direct effect of TSH on bone metabolism while ruling out the direct effect of thyroid hormone on bone metabolism. Thus, we aimed to investigate the relationship between subclinical thyroid dysfunction and bone mineral metabolism in women.
  
  
  METHODS
  We enrolled 413 women (mean age: 52.2 +/- 6.6 years) in our study. Serum levels of TSH, free T4 and the biochemical markers of bone turnover were measured by the standard methods. BMD at the lumbar spine and femoral neck were measured by dual energy X-ray absorptiometry.
  
  
  RESULTS
  Femoral neck BMD was significantly reduced both in the subclinical hyperthyroid group and in the subclinical hypothyroid group as compared with the euthyroid group (one-way ANOVA, p <0.001; post-hoc analysis, p = 0.041, p = 0.033). In contrast to the femoral neck BMD, the lumbar spine BMD showed no difference between the two groups. Additionally, serum calcium and alkaline phosphatase levels, urine deoxypyridinoline levels, and urine calcium to creatinine ratio showed no differences between the two groups.
  
  
  CONCLUSIONS
  Women having subclinical hyperthyroidism and women with subclinical hypothyroidsm have reduced femoral neck BMD. Additional studies are required to elucidate the mechanism for this finding.
authors.affiliation: Department of Internal Medicine, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Won Young
authors.initials: WY
authors.lastname: Lee
authors.forename: Ki Won
authors.initials: KW
authors.lastname: Oh
authors.forename: Eun Jung
authors.initials: EJ
authors.lastname: Rhee
authors.forename: Chan Hee
authors.initials: CH
authors.lastname: Jung
authors.forename: Sun Woo
authors.initials: SW
authors.lastname: Kim
authors.forename: Eun Joo
authors.initials: EJ
authors.lastname: Yun
authors.forename: Hyun Jung
authors.initials: HJ
authors.lastname: Tae
authors.forename: Ki Hyun
authors.initials: KH
authors.lastname: Baek
authors.forename: Moo Il
authors.initials: MI
authors.lastname: Kang
authors.forename: Moon Gi
authors.initials: MG
authors.lastname: Choi
authors.forename: Hyung Joon
authors.initials: HJ
authors.lastname: Yoo
authors.forename: Sung Woo
authors.initials: SW
authors.lastname: Park
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers; D015992:Body Mass Index; D015519:Bone Density / Q000502:physiology*; D005260:Female; D005272:Femur Neck / Q000502:physiology*; D006801:Humans; D008593:Menopause; D008875:Middle Aged; D013959:Thyroid Diseases / Q000503:physiopathology*
chemical_list: D015415:Biomarkers