title: Risk of Late Relapse or Reinfection With Hepatitis C Virus After Achieving a Sustained Virological Response: A Systematic Review and Meta-analysis.
abstract: BACKGROUND
  Treatment for hepatitis C virus (HCV) can lead to sustained virological response (SVR) in over 90% of people. Subsequent recurrence of HCV, either from late relapse or reinfection, reverses the beneficial effects of SVR.
  
  
  METHODS
  A search identified studies analysing HCV recurrence post-SVR. The recurrence rate for each study was calculated using events/person years of follow-up (PYFU). Results were pooled using a random-effects model and used to calculate 5-year recurrence risk. Three patient groups were analysed: (1) Mono-HCV infected "low-risk" patients; (2) Mono-HCV infected "high-risk" patients (injecting drug users or prisoners); (3) human immunodeficiency virus (HIV)/HCV coinfected patients. Recurrence was defined as confirmed HCV RNA detectability post-SVR.
  
  
  RESULTS
  In the 43 studies of HCV mono-infected "low-risk" patients (n = 7969) the pooled recurrence rate was 1.85/1000 PYFU (95% confidence interval [CI], .71-3.35; I(2) = 73%) leading to a summary 5-year recurrence risk of 0.95% (95% CI, .35%-1.69%). For the 14 studies of HCV monoinfected "high-risk" patients (n = 771) the pooled recurrence rate was 22.32/1000 PYFU (95% CI, 13.07-33.46; I(2) = 27%) leading to a summary 5-year risk of 10.67% (95% CI, 6.38%-15.66%). For the 4 studies of HIV/HCV coinfected patients the pooled recurrence rate was 32.02/1000 PYFU (95% CI, .00-123.49; I(2) = 96%) leading to a summary 5-year risk of 15.02% (95% CI, .00%-48.26%). The higher pooled estimates of recurrence in the high-risk and coinfected cohorts were driven by an increase in reinfection rather than late relapse.
  
  
  CONCLUSIONS
  SVR appears durable in the majority of patients at 5 years post-treatment. The large difference in 5 year event rate by risk group is driven mainly by an increased reinfection risk.
authors.affiliation: Division of Medicine, Imperial College London.
authors.forename: Bryony
authors.initials: B
authors.lastname: Simmons
authors.affiliation: Division of Medicine, Imperial College London.
authors.forename: Jawaad
authors.initials: J
authors.lastname: Saleem
authors.affiliation: Pharmacology and Therapeutics, Liverpool University.
authors.forename: Andrew
authors.initials: A
authors.lastname: Hill
authors.affiliation: Research Institute of Primary Care and Health Sciences, Keele University, Staffordshire, United Kingdom.
authors.forename: Richard D
authors.initials: RD
authors.lastname: Riley
authors.affiliation: Division of Medicine, Imperial College London.
authors.forename: Graham S
authors.initials: GS
authors.lastname: Cooke
mesh_terms: D000293:Adolescent; D000328:Adult; D000998:Antiviral Agents / Q000627:therapeutic use; D060085:Coinfection / Q000188:drug therapy / Q000821:virology; D055030:Drug Users; D005260:Female; D005500:Follow-Up Studies; D015658:HIV Infections / Q000453:epidemiology / Q000821:virology; D016174:Hepacivirus / Q000235:genetics / Q000302:isolation & purification; D006526:Hepatitis C / Q000188:drug therapy* / Q000453:epidemiology / Q000821:virology*; D019698:Hepatitis C, Chronic / Q000188:drug therapy* / Q000453:epidemiology / Q000821:virology*; D006801:Humans; D008297:Male; D012367:RNA, Viral / Q000235:genetics; D012008:Recurrence; D012254:Ribavirin / Q000627:therapeutic use; D012307:Risk Factors; D000072230:Sustained Virologic Response; D019562:Viral Load; D055815:Young Adult
chemical_list: D000998:Antiviral Agents; D012367:RNA, Viral; D012254:Ribavirin
keywords: hepatitis C; recurrence; reinfection; relapse; sustained virologic response