title: Prevalence of vitamin D insufficiency among adolescents and its correlation with bone parameters using high-resolution peripheral quantitative computed tomography.
abstract: Vitamin D deficiency and insufficiency are highly prevalent among adolescents in Hong Kong, which is a sub-tropical city with ample sunshine. Vitamin D level is significantly correlated with key bone density and bone quality parameters. Further interventional studies are warranted to define the role of vitamin D supplementation for improvement of bone health among adolescents.
  
  
  
  The relationship between bone quality parameters and vitamin D (Vit-D) status remains undefined among adolescents. The aims of this study were to evaluate Vit-D status and its association with both bone density and bone quality parameters among adolescents.
  
  
  
  Three hundred thirty-three girls and 230 boys (12-16 years old) with normal health were recruited in summer and winter separately from local schools. Serum 25(OH) Vit-D level, bone density and quality parameters by Dual Energy X-ray Absorptiometry (DXA) and High-Resolution peripheral Quantitative Computed Tomography (HR-pQCT), dietary calcium intake, and physical activity level were assessed.
  
  
  
  Sixty-four point seven percent and 11.4 % of subjects were insufficient [25 ≤ 25(OH)Vit-D ≤ 50 nmol/L] and deficient [25(OH)Vit-D < 25 nmol/L] in Vit-D, respectively. The mean level of serum 25(OH)Vit-D in summer was significantly higher than that in winter (44.7 ± 13.6 and 35.9 ± 12.6 nmol/L, respectively) without obvious gender difference. In girls, areal bone mineral density (aBMD) and bone mineral content (BMC) of bilateral femoral necks, cortical area, cortical thickness, total volumetric bone mineral density (vBMD), and trabecular thickness were significantly correlated with 25(OH)Vit-D levels. In boys, aBMD of bilateral femoral necks, BMC of the dominant femoral neck, cortical area, cortical thickness, total vBMD, trabecular vBMD, BV/TV, and trabecular separation were significantly correlated with 25(OH)Vit-D levels.
  
  
  
  Vit-D insufficiency was highly prevalent among adolescents in Hong Kong with significant correlation between Vit-D levels and key bone density and bone quality parameters being detected in this study. Given that this is a cross-sectional study and causality relationship cannot be inferred, further interventional studies investigating the role of Vit-D supplementation on improving bone health among adolescents are warranted.
authors.affiliation: Bone Quality and Health Centre, Department of Orthopaedics and Traumatology, Faculty of Medicine, The Chinese University of Hong Kong, Prince of Wales Hospital, General Office, 5/F LCW Clinical Sciences Building, Sha Tin, NT, Hong Kong, China.
authors.forename: T F
authors.initials: TF
authors.lastname: Cheung
authors.affiliation: Bone Quality and Health Centre, Department of Orthopaedics and Traumatology, Faculty of Medicine, The Chinese University of Hong Kong, Prince of Wales Hospital, General Office, 5/F LCW Clinical Sciences Building, Sha Tin, NT, Hong Kong, China.
authors.forename: K Y
authors.initials: KY
authors.lastname: Cheuk
authors.affiliation: Bone Quality and Health Centre, Department of Orthopaedics and Traumatology, Faculty of Medicine, The Chinese University of Hong Kong, Prince of Wales Hospital, General Office, 5/F LCW Clinical Sciences Building, Sha Tin, NT, Hong Kong, China.
authors.forename: F W P
authors.initials: FW
authors.lastname: Yu
authors.affiliation: Bone Quality and Health Centre, Department of Orthopaedics and Traumatology, Faculty of Medicine, The Chinese University of Hong Kong, Prince of Wales Hospital, General Office, 5/F LCW Clinical Sciences Building, Sha Tin, NT, Hong Kong, China.
authors.forename: V W Y
authors.initials: VW
authors.lastname: Hung
authors.affiliation: Department of Chemical Pathology, Faculty of Medicine, The Chinese University of Hong Kong, Sha Tin, Hong Kong, China.
authors.forename: C S
authors.initials: CS
authors.lastname: Ho
authors.affiliation: Bone Quality and Health Centre, Department of Orthopaedics and Traumatology, Faculty of Medicine, The Chinese University of Hong Kong, Prince of Wales Hospital, General Office, 5/F LCW Clinical Sciences Building, Sha Tin, NT, Hong Kong, China.
authors.forename: T Y
authors.initials: TY
authors.lastname: Zhu
authors.affiliation: Bone Quality and Health Centre, Department of Orthopaedics and Traumatology, Faculty of Medicine, The Chinese University of Hong Kong, Prince of Wales Hospital, General Office, 5/F LCW Clinical Sciences Building, Sha Tin, NT, Hong Kong, China.
authors.forename: B K W
authors.initials: BK
authors.lastname: Ng
authors.affiliation: Lee Hysan Clinical Research Laboratory, Faculty of Medicine, The Chinese University of Hong Kong, Sha Tin, Hong Kong, China.
authors.forename: K M
authors.initials: KM
authors.lastname: Lee
authors.affiliation: Bone Quality and Health Centre, Department of Orthopaedics and Traumatology, Faculty of Medicine, The Chinese University of Hong Kong, Prince of Wales Hospital, General Office, 5/F LCW Clinical Sciences Building, Sha Tin, NT, Hong Kong, China.
authors.forename: L
authors.initials: L
authors.lastname: Qin
authors.affiliation: The Jockey Club School of Public Health and Primary Care, Faculty of Medicine, The Chinese University of Hong Kong, Sha Tin, Hong Kong, China.
authors.forename: S S Y
authors.initials: SS
authors.lastname: Ho
authors.affiliation: Department of Paediatrics, Faculty of Medicine, The Chinese University of Hong Kong, Sha Tin, Hong Kong, China.
authors.forename: G W K
authors.initials: GW
authors.lastname: Wong
authors.affiliation: Bone Quality and Health Centre, Department of Orthopaedics and Traumatology, Faculty of Medicine, The Chinese University of Hong Kong, Prince of Wales Hospital, General Office, 5/F LCW Clinical Sciences Building, Sha Tin, NT, Hong Kong, China.|SH Ho Scoliosis Research Laboratory, Sha Tin, Hong Kong, China.
authors.forename: J C Y
authors.initials: JC
authors.lastname: Cheng
authors.affiliation: Bone Quality and Health Centre, Department of Orthopaedics and Traumatology, Faculty of Medicine, The Chinese University of Hong Kong, Prince of Wales Hospital, General Office, 5/F LCW Clinical Sciences Building, Sha Tin, NT, Hong Kong, China. tplam@ort.cuhk.edu.hk.|SH Ho Scoliosis Research Laboratory, Sha Tin, Hong Kong, China. tplam@ort.cuhk.edu.hk.
authors.forename: T P
authors.identifier: 0000-0002-2427-2719
authors.initials: TP
authors.lastname: Lam
mesh_terms: D015502:Absorptiometry, Photon; D000293:Adolescent; D015519:Bone Density; D002648:Child; D003430:Cross-Sectional Studies; D005260:Female; D005272:Femur Neck / Q000000981:diagnostic imaging; D006723:Hong Kong; D006801:Humans; D008297:Male; D015995:Prevalence; D012621:Seasons; D014057:Tomography, X-Ray Computed; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood; D014808:Vitamin D Deficiency / Q000000981:diagnostic imaging / Q000453:epidemiology*
chemical_list: D014807:Vitamin D; C104450:25-hydroxyvitamin D
keywords: Adolescent; Bone quality; DXA; HR-pQCT; Vitamin D insufficiency