title: Circulating 25-hydroxyvitamin D concentrations are correlated with cardiometabolic risk among American black and white adolescents living in a year-round sunny climate.
abstract: OBJECTIVE
  Low vitamin D status is common among healthy black and white adolescents residing at southern U.S. latitudes with a year-round sunny climate. Thus we aimed to study the relationships between circulating 25-hydroxyvitamin D [25(OH)D] and cardiometabolic risk factors in this population.
  
  
  METHODS
  25(OH)D concentrations were measured with liquid chromatography tandem mass spectroscopy in 701 girls and boys (14-18 years old, 54% blacks, 49% females). Cardiometabolic risk was indexed by adipokines, inflammatory markers, fasting glucose, homeostatic model assessment-insulin resistance (HOMA-IR), lipid profile, and blood pressure (BP).
  
  
  RESULTS
  Controlling for age, sex, race, sexual maturation, season, physical activity, and percent body fat, 25(OH)D concentrations were significantly correlated with adiponectin (r = 0.06, P = 0.05), leptin (r = -0.32, P < 0.01), fibrinogen (r = -0.05, P = 0.03), glucose (r = -0.16, P = 0.02), HOMA-IR (r = -0.17, P < 0.01), HDL cholesterol (r = 0.14, P = 0.02), systolic BP (r = -0.10, P = 0.02), and diastolic BP (r = -0.21, P < 0.01). When 25(OH)D concentrations were stratified into increasing tertiles, there were significant linear upward trends for adiponectin (P = 0.01) and HDL cholesterol (P = 0.04), but significant linear down trends for glucose (P < 0.01), HOMA-IR (P < 0.01), and systolic BP (P < 0.01), after adjusting for the above covariates.
  
  
  CONCLUSIONS
  Circulating 25(OH)D concentrations are associated with various adverse cardiometabolic risk factors, independent of adiposity. Clinical trials addressing the effects of vitamin D supplementation on cardiometabolic risk are warranted in adolescents irrespective of their geographical regions.
authors.affiliation: Corresponding author: Yanbin Dong, ydong@georgiahealth.edu.
authors.forename: Samip
authors.initials: S
authors.lastname: Parikh
authors.forename: De-Huang
authors.initials: DH
authors.lastname: Guo
authors.forename: Norman K
authors.initials: NK
authors.lastname: Pollock
authors.forename: Karen
authors.initials: K
authors.lastname: Petty
authors.forename: Jigar
authors.initials: J
authors.lastname: Bhagatwala
authors.forename: Bernard
authors.initials: B
authors.lastname: Gutin
authors.forename: Chris
authors.initials: C
authors.lastname: Houk
authors.forename: Haidong
authors.initials: H
authors.lastname: Zhu
authors.forename: Yanbin
authors.initials: Y
authors.lastname: Dong
mesh_terms: D054392:Adipokines / Q000097:blood; D052242:Adiponectin / Q000097:blood; D050154:Adiposity; D000293:Adolescent; D001741:Black or African American; D001786:Blood Glucose / Q000378:metabolism; D001794:Blood Pressure / Q000502:physiology; D002980:Climate; D005215:Fasting / Q000097:blood; D005260:Female; D005340:Fibrinogen / Q000378:metabolism; D006801:Humans; D020738:Leptin / Q000097:blood; D008297:Male; D009043:Motor Activity; D013472:Sunlight; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood; D044465:White People
chemical_list: D054392:Adipokines; D052242:Adiponectin; D001786:Blood Glucose; D020738:Leptin; D014807:Vitamin D; D005340:Fibrinogen; C104450:25-hydroxyvitamin D