title: In HIV/hepatitis C virus co-infected patients, higher 25-hydroxyvitamin D concentrations were not related to hepatitis C virus treatment responses but were associated with ritonavir use.
abstract: BACKGROUND
  Among patients with hepatitis C virus (HCV) monoinfection, 25-hydroxyvitamin D [25(OH)D] concentrations are positively associated with a response to peg-interferon/ribavirin. Data on the relation between 25(OH)D concentrations and HCV treatment response in HIV-infected patients are limited.
  
  
  OBJECTIVE
  The objective was to determine whether baseline 25(OH)D concentrations predict virologic response in HIV/HCV co-infected patients and to examine variables associated with 25(OH)D concentrations ≥30 ng/mL.
  
  
  METHODS
  Data and samples from 144 HCV genotype 1, treatment-naive patients from a completed HCV treatment trial were examined in this retrospective study. Early virologic response (EVR) was defined as ≥2 log10 reduction in HCV RNA and/or HCV RNA <600 IU/mL at week 12 of peg-interferon/ribavirin treatment. Baseline 25(OH)D was measured by liquid chromatography/tandem mass spectrometry.
  
  
  RESULTS
  Compared with the non-EVR control group (n = 68), the EVR group (n = 76) was younger, had fewer cirrhotic subjects, had a higher proportion with the IL28B CC genotype, had a higher albumin concentration, and had a lower HCV viral load at baseline (P ≤ 0.05). The difference in baseline 25(OH)D concentrations between EVR and non-EVR patients was not statistically significant (median: 25 ng/mL compared with 20 ng/mL; P = 0.23). Similar results were found for sustained virologic response (SVR). In multivariable analysis, white and Hispanic race-ethnicity (OR: 6.26; 95% CI: 2.47, 15.88; P = 0.0001) and ritonavir use (OR: 2.68; 95% CI: 1.08, 6.65; P = 0.033) were associated with higher 25(OH)D concentrations (≥30 ng/mL).
  
  
  CONCLUSIONS
  Baseline 25(OH)D concentrations did not predict EVR or SVR. Because ritonavir impairs the conversion of 25(OH)D to the active metabolite, utilization of 25(OH)D may have been impaired in subjects taking ritonavir. This trial was registered at www.clinicaltrials.gov as NCT00078403.
authors.affiliation: Divisions of Liver Diseases and Nephrology, Mount Sinai School of Medicine, New York, NY 10029, USA. andrea.branch@mssm.edu
authors.forename: Andrea D
authors.initials: AD
authors.lastname: Branch
authors.forename: Minhee
authors.initials: M
authors.lastname: Kang
authors.forename: Kimberly
authors.initials: K
authors.lastname: Hollabaugh
authors.forename: Christina M
authors.initials: CM
authors.lastname: Wyatt
authors.forename: Raymond T
authors.initials: RT
authors.lastname: Chung
authors.forename: Marshall J
authors.initials: MJ
authors.lastname: Glesby
mesh_terms: D000328:Adult; D000998:Antiviral Agents / Q000627:therapeutic use; D060085:Coinfection; D004359:Drug Therapy, Combination; D005260:Female; D005838:Genotype; D006678:HIV; D015658:HIV Infections / Q000188:drug therapy*; D016174:Hepacivirus; D006526:Hepatitis C / Q000188:drug therapy*; D006801:Humans; D016898:Interferon-alpha / Q000627:therapeutic use; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D012367:RNA, Viral / Q000302:isolation & purification; D012189:Retrospective Studies; D012254:Ribavirin / Q000627:therapeutic use; D019438:Ritonavir / Q000627:therapeutic use*; D019562:Viral Load; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood
chemical_list: D000998:Antiviral Agents; D016898:Interferon-alpha; D012367:RNA, Viral; D014807:Vitamin D; D012254:Ribavirin; C104450:25-hydroxyvitamin D; D019438:Ritonavir