title: Subclinical thyroid dysfunction and hip fracture and bone mineral density in older adults: the cardiovascular health study.
abstract: BACKGROUND
  Subclinical thyroid dysfunction is common in the elderly, yet its relationship with hip fracture and bone mineral density (BMD) is unclear.
  
  
  OBJECTIVE
  We examined the association between endogenous subclinical hyper- and hypothyroidism and hip fracture and BMD in older adults.
  
  
  METHODS
  A total of 4936 US individuals 65 years old or older enrolled in the Cardiovascular Health Study and not taking thyroid preparations were included. Analyses of incident hip fracture were performed by thyroid status, over a median follow-up of 12 years. A cross-sectional analysis of thyroid status and BMD was performed in a subset of 1317 participants who had dual-energy x-ray absorptiometry scans. Models were adjusted for risk factors and stratified by sex.
  
  
  RESULTS
  No association was found between subclinical hypothyroidism and incident hip fracture compared with euthyroidism, when assessed at a single time point or persisting at two time points, in either women [hazard ratio (HR) 0.91, 95% confidence interval (CI) 0.69-1.20 for a single and HR 0.79, 95% CI 0.52-1.21 for two time points] or men (HR 1.27, 95% CI 0.82-1.95 for a single and HR 1.09, 95% CI 0.57-2.10 for two time points). Likewise, no association was found between subclinical hyperthyroidism and incident hip fracture in either sex (HR 1.11, 95% CI 0.55-2.25 in women and HR 1.78, 95% CI 0.56-5.66 in men). No association was found between subclinical thyroid dysfunction and BMD at the lumbar spine, total hip, or femoral neck sites.
  
  
  CONCLUSIONS
  Our data suggest no association between subclinical hypothyroidism or subclinical hyperthyroidism and hip fracture risk or BMD in older men and women. Additional data are needed to improve the precision of estimates for subclinical hyperthyroidism and in men.
authors.affiliation: Division of Endocrinology, Diabetes, and Metabolism (M.C.G., A.R.C.), Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104; Department of Biostatistics (A.M.A.), University of Washington, Seattle, Washington 98155; Division of Endocrinology, Gerontology, and Metabolism (J.S.L.), Stanford University School of Medicine and Veterans Affairs Palo Alto Health Care System (J.S.L.), Palo Alto, California 94305; and Division of General Medicine (J.R.), University of California, Davis, Sacramento, California 95817.
authors.forename: Margaret C
authors.initials: MC
authors.lastname: Garin
authors.forename: Alice M
authors.initials: AM
authors.lastname: Arnold
authors.forename: Jennifer S
authors.initials: JS
authors.lastname: Lee
authors.forename: John
authors.initials: J
authors.lastname: Robbins
authors.forename: Anne R
authors.initials: AR
authors.lastname: Cappola
mesh_terms: D015502:Absorptiometry, Photon; D000368:Aged; D000369:Aged, 80 and over; D058070:Asymptomatic Diseases; D015519:Bone Density; D002319:Cardiovascular System; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D005260:Female; D006620:Hip Fractures / Q000000981:diagnostic imaging / Q000453:epidemiology*; D006801:Humans; D008297:Male; D058866:Osteoporotic Fractures / Q000000981:diagnostic imaging / Q000453:epidemiology*; D012307:Risk Factors; D012737:Sex Factors; D013959:Thyroid Diseases / Q000453:epidemiology*