title: Poor vitamin D status is prospectively associated with greater muscle mass loss in middle-aged and elderly Chinese individuals.
abstract: BACKGROUND
  Poor vitamin D status can increase age-related muscle mass loss. However, existing prospective evidence is limited and controversial.
  
  
  OBJECTIVE
  This study aimed to investigate the association of plasma 25-hydroxyvitamin D [25(OH)D] with muscle mass loss in middle-aged and elderly Chinese individuals over 6 years.
  
  
  METHODS
  We conducted a prospective cohort study.
  
  
  METHODS
  This community-based study included 568 men and women aged 50 to 70 years at baseline.
  
  
  METHODS
  Baseline plasma concentrations of 25(OH)D and biomarkers of liver and kidney functions and inflammation were measured. Body composition was assessed at baseline and 6-year follow-up by dual-energy x-ray absorptiometry. Appendicular skeletal muscle mass (ASMM) and trunk lean mass were calculated and total body lean mass was defined as an overall measure of total nonfat and nonbone tissues.
  
  
  METHODS
  Descriptive statistics and multiple linear regression were applied.
  
  
  RESULTS
  The 6-year loss of ASMM was 1.14 kg (5.3%) in men and 0.47 kg (3.1%) in women (all P values <0.001). Compared with the highest 25(OH)D tertile, participants in the lowest tertile had significantly more absolute loss of ASMM (-1.21 vs -1.00 kg; P for trend=0.024) after multivariate adjustments for conventional confounders, as well as protein intake. The association persisted after additional adjustment of bone mineral density and inflammatory markers (P for trend=0.017). No significant associations were detected between 25(OH)D and absolute loss of trunk lean mass or total body lean mass.
  
  
  CONCLUSIONS
  Lower 25(OH)D concentrations were prospectively associated with greater ASMM loss in middle-aged and elderly Chinese individuals independent of bone mineral density, inflammation, diet, and other risk factors.
authors.forename: Gang
authors.initials: G
authors.lastname: Liu
authors.forename: Ling
authors.initials: L
authors.lastname: Lu
authors.forename: Qi
authors.initials: Q
authors.lastname: Sun
authors.forename: Xingwang
authors.initials: X
authors.lastname: Ye
authors.forename: Liang
authors.initials: L
authors.lastname: Sun
authors.forename: Xin
authors.initials: X
authors.lastname: Liu
authors.forename: Geng
authors.initials: G
authors.lastname: Zong
authors.forename: Qianlu
authors.initials: Q
authors.lastname: Jin
authors.forename: Huaixing
authors.initials: H
authors.lastname: Li
authors.forename: Xu
authors.initials: X
authors.lastname: Lin
mesh_terms: D015652:25-Hydroxyvitamin D 2 / Q000097:blood; D000368:Aged; D000375:Aging; D015415:Biomarkers / Q000097:blood; D002112:Calcifediol / Q000097:blood; D002681:China; D015331:Cohort Studies; D005260:Female; D006306:Health Surveys; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000473:pathology; D009752:Nutritional Status; D011446:Prospective Studies; D055948:Sarcopenia / Q000097:blood / Q000209:etiology* / Q000473:pathology / Q000503:physiopathology; D012720:Severity of Illness Index; D012727:Sex Characteristics; D014808:Vitamin D Deficiency / Q000503:physiopathology*
chemical_list: D015415:Biomarkers; D015652:25-Hydroxyvitamin D 2; D002112:Calcifediol
keywords: 25-hydroxyvitamin D; Cohort study; Dual-energy x-ray absorptiometry; Inflammation; Muscle mass