title: Incomplete adherence to antiretroviral therapy is associated with higher levels of residual HIV-1 viremia.
abstract: OBJECTIVE
  To evaluate the relationship between incomplete antiretroviral therapy (ART) adherence and levels of residual HIV-1 viremia.
  
  
  METHODS
  Medication adherence and residual viremia less than 50 copies/ml were quantified in participants of a cohort of homeless and marginally housed individuals with HIV/AIDS.
  
  
  METHODS
  Participants had at least 6 months of virologic suppression of less than 50 copies/ml and were in the adherence monitoring cohort with monthly unannounced pill counts. Residual viremia was measured by the single-copy assay.
  
  
  RESULTS
  The median average ART adherence over the prior 1 and 2 months were 94% [interquartile range (IQR) 79-100%] and 93% (IQR 82-98%), respectively. Average ART adherence over the past 2 months was significantly associated with levels of residual HIV viremia (Spearman r = -0.25, P = 0.04). One-third of participants with 100% ART adherence over the past 2 months had detectable residual viremia. On multivariate regression analysis, ART adherence over the past 2 months, but not duration of virologic suppression, CD4 T-cell count or ART regimen, was significantly associated with levels of residual HIV viremia. Detectable residual viremia was associated with virologic failure (>50 copies/ml) on univariate Cox proportional hazard analysis (hazard ratio 2.08, P = 0.02). However, on multivariate analysis, only ART adherence was associated with risk of virologic failure.
  
  
  CONCLUSIONS
  Incomplete ART adherence is associated with higher levels of residual HIV-1 viremia, but detectable residual viremia can be present despite 100% measured ART adherence.
authors.affiliation: Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: Jonathan Z
authors.initials: JZ
authors.lastname: Li
authors.affiliation: Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.|Hôpital Saint Louis, Paris, France.
authors.forename: Sebastien
authors.initials: S
authors.lastname: Gallien
authors.affiliation: Center for Biostatistics in AIDS Research, Harvard School of Public Health, Boston, MA, USA.
authors.forename: Heather
authors.initials: H
authors.lastname: Ribaudo
authors.affiliation: Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: Andrea
authors.initials: A
authors.lastname: Heisey
authors.affiliation: Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: David R
authors.initials: DR
authors.lastname: Bangsberg
authors.affiliation: Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: Daniel R
authors.initials: DR
authors.lastname: Kuritzkes
mesh_terms: D000328:Adult; D044966:Anti-Retroviral Agents / Q000008:administration & dosage*; D023241:Antiretroviral Therapy, Highly Active / Q000379:methods*; D005260:Female; D015658:HIV Infections / Q000188:drug therapy* / Q000821:virology; D015497:HIV-1 / Q000302:isolation & purification*; D006801:Humans; D008297:Male; D008875:Middle Aged; D019562:Viral Load; D014766:Viremia; D016903:Drug Monitoring
chemical_list: D044966:Anti-Retroviral Agents