title: Cross-sectional study of vitamin D levels, immunologic and virologic outcomes in HIV-infected adults.
abstract: BACKGROUND
  Vitamin D is increasingly recognized as an important immunomodulator. Lower levels of 25-hydroxyvitamin D (25[OH]D) and 1,25-dihydroxyvitamin D (1,25[OH]2D) are observed in persons living with HIV.
  
  
  OBJECTIVE
  The purpose of this study was to evaluate the relationship of 25(OH)D, and 1,25(OH)2D to HIV viral load, and CD4+ T cells in HIV-infected adults.
  
  
  METHODS
  This was a cross-sectional study completed between January 2010 and April 2011.
  
  
  METHODS
  This study was conducted with volunteers who received HIV care in Wisconsin at either a University-based HIV clinic or an urban community HIV clinic.
  
  
  METHODS
  One hundred twelve adults with HIV infection participated in this study.
  
  
  METHODS
  The primary outcome for this study was the relationship between 1,25(OH)2D and HIV viral load. Secondary outcomes included relationships between 25(OH)D and HIV viral load, 25(OH)D and 1,25(OH)2D to CD4+ T cells, and predictors of vitamin D deficiency.
  
  
  RESULTS
  The 112 volunteers included 24 women and 3 transgender individuals; 68% were from the university clinic, and 32% were from the urban clinic. Mean age was 44.2 years. The mean 25(OH)D level was 22.5 ng/mL; mean 1,25(OH)2D level was 23.5 pg/mL. Twenty-two percent had 25(OH)D ≤10 ng/mL; 53% had values <20 ng/mL, and 73% were ≤30 ng/mL. There was no association between vitamin D and CD4. A nonlinear relationship between viral load and 1,25(OH)2D was found. For 1,25(OH)2D below 32 pg/mL, for each 10 pg/mL decrease in 1,25(OH)2D, (log10) viral load increased by 0.84 (95% CI: 0.16-1.51, P = .015). For 1,25(OH)2D above 32 pg/mL, for each 10 pg/mL increase in 1,25(OH)2D, (log10) viral load increased by 0.36 (95% CI: 0.15-0.57, P = .0009).
  
  
  CONCLUSIONS
  Vitamin D deficiency was common in this HIV population, as seen in other HIV cohorts. A novel, U-shaped relationship between 1,25(OH)2D and viral load, with the lowest and highest 1,25(OH)2D levels seen with high viral loads, was found and deserves further study.
authors: University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA. allison.bearden@usc-mca.org
authors: Allison
authors: A
authors: Bearden
authors: Cybele
authors: C
authors: Abad
authors: Ron
authors: R
authors: Gangnon
authors: James M
authors: JM
authors: Sosman
authors: Neil
authors: N
authors: Binkley
authors: Nasia
authors: N
authors: Safdar
mesh_terms: D000328:Adult; D018791:CD4 Lymphocyte Count; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D005260:Female; D015658:HIV Infections / Q000097:blood / Q000150:complications* / Q000175:diagnosis* / Q000276:immunology; D015497:HIV-1 / Q000276:immunology / Q000502:physiology; D006801:Humans; D007107:Immune System / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012621:Seasons; D019562:Viral Load / Q000276:immunology; D014807:Vitamin D / Q000097:blood*; D014808:Vitamin D Deficiency / Q000097:blood / Q000150:complications* / Q000276:immunology / Q000821:virology
chemical_list: D014807:Vitamin D