title: Serum 25-hydroxyvitamin D levels and rate of hip bone loss in older men.
abstract: BACKGROUND
  Vitamin D deficiency is common among older adults, but the association between 25-hydroxyvitamin D [25(OH)D] levels and rates of bone loss is uncertain.
  
  
  OBJECTIVE
  Our aim was to test the hypothesis that lower 25(OH)D levels are associated with higher rates of hip bone loss in older men.
  
  
  METHODS
  We conducted a prospective cohort study in six U.S. centers.
  
  
  METHODS
  A total of 1279 community-dwelling men aged 65 yr or older with 25(OH)D levels (liquid chromatography-tandem mass spectroscopy) and hip bone mineral density (BMD) (dual-energy x-ray absorptiometry) at baseline and repeat hip BMD an average of 4.4 yr later participated in the study.
  
  
  METHODS
  We measured the annualized percentage rate of change in hip BMD.
  
  
  RESULTS
  After adjustment for multiple potential confounders, the average rate of decline in total hip BMD was -0.59%/yr among men with 25(OH)D levels below 15.0 ng/ml, -0.54%/yr among men with 25(OH)D levels 15.0-19.9 ng/ml, -0.35%/yr among men with 25(OH)D levels 20.0-29.9 ng/ml, and -0.37%/yr among men with 25(OH)D levels of at least 30 ng/ml (P trend = 0.008 for multivariable model). Evidence was strong to support an association among men aged 75 yr and older (P trend <0.001), but not among younger men (P trend = 0.55). Findings were similar when 25(OH)D level was expressed in quintiles and when BMD at hip subregions was substituted for total hip BMD.
  
  
  CONCLUSIONS
  In this cohort of community-dwelling older men, men with 25(OH)D levels below 20 ng/ml had greater subsequent rates of hip bone loss, but rates of loss were similar among men with higher levels. These results lend support to the view that low 25(OH)D levels are detrimental to BMD in older men.
authors.affiliation: Center for Chronic Disease Outcomes Research, VA Medical Center, One Veterans Drive (111-0), Minneapolis, MN 55417, USA. ensru001@umn.edu
authors.forename: Kristine E
authors.initials: KE
authors.lastname: Ensrud
authors.forename: Brent C
authors.initials: BC
authors.lastname: Taylor
authors.forename: Misti L
authors.initials: ML
authors.lastname: Paudel
authors.forename: Jane A
authors.initials: JA
authors.lastname: Cauley
authors.forename: Peggy M
authors.initials: PM
authors.lastname: Cawthon
authors.forename: Steven R
authors.initials: SR
authors.lastname: Cummings
authors.forename: Howard A
authors.initials: HA
authors.lastname: Fink
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Barrett-Connor
authors.forename: Joseph M
authors.initials: JM
authors.lastname: Zmuda
authors.forename: James M
authors.initials: JM
authors.lastname: Shikany
authors.forename: Eric S
authors.initials: ES
authors.lastname: Orwoll
mesh_terms: D000368:Aged; D015519:Bone Density; D015331:Cohort Studies; D006801:Humans; D008297:Male; D010024:Osteoporosis / Q000097:blood / Q000453:epidemiology*; D010384:Pelvic Bones / Q000473:pathology*; D011446:Prospective Studies; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood
chemical_list: D014807:Vitamin D; C104450:25-hydroxyvitamin D