title: Are previous treatment interruptions associated with higher viral rebound rates in patients with viral suppression?
abstract: OBJECTIVE
  We investigated whether previous treatment interruptions are associated with a raised risk of viral rebound in individuals who have attained virological suppression.
  
  
  METHODS
  All patients achieving an undetectable viral load while on therapy were followed until viral rebound or the time of the last viral load. Poisson regression was used to describe the independent impact of treatment interruptions on rebound rates.
  
  
  RESULTS
  A total of 12,977 patients from the United Kingdom Collaborative HIV Cohort (UK CHIC) Study achieved a viral load of less than 50 copies/ml. These patients contributed a total of 37,314 person-years of follow-up. The overall rebound rate was 8.07 (7.78, 8.36) per 100 person-years. In adjusted analyses, rates of viral rebound were up to 64% higher (rate ratio 1.64; 1.43, 1.88) in those who had previously interrupted therapy compared with those who had not. Patients who had interrupted at detectable viral loads had up to a 74% (1.74; 1.42, 2.14) higher chance of rebounding compared with those who had not interrupted with a detectable viral load. We found no evidence to suggest interrupting treatment at an undetectable viral load was associated with viral rebound.
  
  
  CONCLUSIONS
  Among patients with an undetectable viral load, having previously interrupted therapy while the viral load was detectable is associated with a raised risk of rebound.
authors.affiliation: Department of Primary Care and Population Sciences, Royal Free and University College Medical School, Hampstead Campus, Rowland Hill Street, London, NW3 2PF, UK. l.bansi@pcps.ucl.ac.uk
authors.forename: Loveleen K
authors.initials: LK
authors.lastname: Bansi
authors.forename: Andrew A
authors.initials: AA
authors.lastname: Benzie
authors.forename: Andrew N
authors.initials: AN
authors.lastname: Phillips
authors.forename: Simon
authors.initials: S
authors.lastname: Portsmouth
authors.forename: Teresa
authors.initials: T
authors.lastname: Hill
authors.forename: Clifford
authors.initials: C
authors.lastname: Leen
authors.forename: Achim
authors.initials: A
authors.lastname: Schwenk
authors.forename: Margaret
authors.initials: M
authors.lastname: Johnson
authors.forename: Jane
authors.initials: J
authors.lastname: Anderson
authors.forename: Richard
authors.initials: R
authors.lastname: Gilson
authors.forename: Philippa
authors.initials: P
authors.lastname: Easterbrook
authors.forename: Brian
authors.initials: B
authors.lastname: Gazzard
authors.forename: Martin
authors.initials: M
authors.lastname: Fisher
authors.forename: Chloe
authors.initials: C
authors.lastname: Orkin
authors.forename: Kholoud
authors.initials: K
authors.lastname: Porter
authors.forename: Deenan
authors.initials: D
authors.lastname: Pillay
authors.forename: Graham P
authors.initials: GP
authors.lastname: Taylor
authors.forename: John C
authors.initials: JC
authors.lastname: Walsh
authors.forename: Caroline A
authors.initials: CA
authors.lastname: Sabin
mesh_terms: D000328:Adult; D019380:Anti-HIV Agents / Q000008:administration & dosage* / Q000627:therapeutic use; D023241:Antiretroviral Therapy, Highly Active; D015331:Cohort Studies; D004334:Drug Administration Schedule; D004359:Drug Therapy, Combination; D005260:Female; D015658:HIV Infections / Q000188:drug therapy* / Q000821:virology; D015497:HIV-1 / Q000502:physiology; D006801:Humans; D008297:Male; D016012:Poisson Distribution; D018894:Reverse Transcriptase Inhibitors / Q000008:administration & dosage* / Q000627:therapeutic use; D017211:Treatment Failure; D006113:United Kingdom; D019562:Viral Load
chemical_list: D019380:Anti-HIV Agents; D018894:Reverse Transcriptase Inhibitors