title: Active vitamin D (1,25-dihydroxyvitamin D) and bone health in middle-aged and elderly men: the European Male Aging Study (EMAS).
abstract: BACKGROUND
  There is little information on the potential impact of serum 1,25-dihydroxyvitamin D [1,25(OH)2D] on bone health including turnover.
  
  
  OBJECTIVE
  The objective of the study was to determine the influence of 1,25(OH)2D and 25-hydroxyvitamin D [25(OH)D] on bone health in middle-aged and older European men.
  
  
  METHODS
  Men aged 40-79 years were recruited from population registers in 8 European centers. Subjects completed questionnaires that included questions concerning lifestyle and were invited to attend for quantitative ultrasound (QUS) of the heel, assessment of height and weight, and a fasting blood sample from which 1,25(OH)2D, 25(OH)D, and PTH were measured. 1,25(OH)2D was measured using liquid chromatography tandem mass spectrometry. Bone markers serum N-terminal propeptide of type 1 procollagen (P1NP) and crosslinks (β-cTX) were also measured. Dual-energy x-ray absorptiometry (DXA) of the hip and lumbar spine was performed in 2 centers.
  
  
  METHODS
  QUS of the heel, bone markers P1NP and β-cTX, and DXA of the hip and lumbar spine were measured.
  
  
  RESULTS
  A total of 2783 men, mean age 60.0 years (SD 11.0) were included in the analysis. After adjustment for age and center, 1,25(OH)2D was positively associated with 25(OH)D but not with PTH. 25(OH)D was negatively associated with PTH. After adjustment for age, center, height, weight, lifestyle factors, and season, 1,25(OH)2D was associated negatively with QUS and DXA parameters and associated positively with β-cTX. 1,25(OH)2D was not correlated with P1NP. 25(OH)D was positively associated with the QUS and DXA parameters but not related to either bone turnover marker. Subjects with both high 1,25(OH)2D (upper tertile) and low 25(OH)D (lower tertile) had the lowest QUS and DXA parameters and the highest β-cTX levels.
  
  
  CONCLUSIONS
  Serum 1,25(OH)2D is associated with higher bone turnover and poorer bone health despite being positively related to 25(OH)D. A combination of high 1,25(OH)2D and low 25(OH)D is associated with the poorest bone health.
authors: Department of Andrology and Endocrinology, Katholieke Universiteit Leuven, B-3001 Leuven, Belgium. dirk.vanderschueren@uzleuven.be
authors: Dirk
authors: D
authors: Vanderschueren
authors: Stephen R
authors: SR
authors: Pye
authors: Terence W
authors: TW
authors: O'Neill
authors: David M
authors: DM
authors: Lee
authors: Ivo
authors: I
authors: Jans
authors: Jaak
authors: J
authors: Billen
authors: Evelien
authors: E
authors: Gielen
authors: Michaël
authors: M
authors: Laurent
authors: Frank
authors: F
authors: Claessens
authors: Judith E
authors: JE
authors: Adams
authors: Kate A
authors: KA
authors: Ward
authors: Gyorgy
authors: G
authors: Bartfai
authors: Felipe F
authors: FF
authors: Casanueva
authors: Joseph D
authors: JD
authors: Finn
authors: Gianni
authors: G
authors: Forti
authors: Aleksander
authors: A
authors: Giwercman
authors: Thang S
authors: TS
authors: Han
authors: Ilpo T
authors: IT
authors: Huhtaniemi
authors: Krzysztof
authors: K
authors: Kula
authors: Michael E J
authors: ME
authors: Lean
authors: Neil
authors: N
authors: Pendleton
authors: Margus
authors: M
authors: Punab
authors: Frederick C W
authors: FC
authors: Wu
authors: Steven
authors: S
authors: Boonen
mesh_terms: D015502:Absorptiometry, Photon; D000328:Adult; D000368:Aged; D000375:Aging / Q000378:metabolism*; D015415:Biomarkers / Q000378:metabolism; D015519:Bone Density / Q000502:physiology; D001851:Bone Diseases, Metabolic / Q000000981:diagnostic imaging / Q000378:metabolism*; D016723:Bone Remodeling / Q000502:physiology*; D002111:Calcaneus / Q000000981:diagnostic imaging / Q000378:metabolism; D002117:Calcitriol / Q000097:blood*; D024042:Collagen Type I / Q000378:metabolism; D006621:Hip Joint / Q000000981:diagnostic imaging; D006801:Humans; D008019:Life Style; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood; D010455:Peptides / Q000378:metabolism; D011795:Surveys and Questionnaires; D014463:Ultrasonography; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood; D014808:Vitamin D Deficiency / Q000378:metabolism*; D044465:White People
chemical_list: D015415:Biomarkers; D024042:Collagen Type I; D010281:Parathyroid Hormone; D010455:Peptides; C052929:collagen type I trimeric cross-linked peptide; D014807:Vitamin D; C097949:1,25-dihydroxyvitamin D; D002117:Calcitriol