title: Factors associated with the immune response to hepatitis A vaccination in HIV-infected patients in the era of highly active antiretroviral therapy.
abstract: BACKGROUND
  HIV seropositivity is considered a risk factor for complications in hepatitis A virus (HAV) infection. HAV vaccination schedules are widely implemented in HIV-infected patients, but the immune response remains impaired.
  
  
  METHODS
  We analysed the response to vaccination (antiHAV titres ≥20IU/l) in 282 HIV-infected patients included in a standard (1440 Elisa Units (EU) at 0, 6 months) or rapidly accelerated schedule (720 EU at 0, 7, 21 days and 6 months) between 1997 and 2009. Factors associated with the response to vaccination were analysed using logistic regression.
  
  
  RESULTS
  The overall response rate was 73.4%. Male sex (OR: 0.16, 95% CI 0.05-0.51) and hepatitis C virus co-infection (OR: 0.30, 95% CI 0.14-0.74) were associated with a lower probability of response. Protective antibody response was associated with a higher CD4/CD8 ratio (OR: 3.69, 95% CI 1.3-10.5) and having received two doses of standard schedule (compared with patients receiving only one dose of the same schedule) (OR: 2.51, 95% CI 1.22-5.15). Three doses of the rapidly accelerated schedule were not more effective than a single dose of 1440 EU (OR: 1.32, 95% CI 0.48-3.63).
  
  
  CONCLUSIONS
  The low responses observed in patients receiving a single dose suggest the need to emphasize adhesion to vaccination protocols to avoid failure. The CD4/CD8 ratio may be considered as an immune status marker which could help to better choose the moment of vaccination. Our findings underscore the importance of identifying strategies that optimize the timing and effectiveness of hepatitis A vaccination in HIV-infected patients and of the need for further studies on individual factors such as sex and hepatitis C co-infection that may affect the response to vaccination. Likewise, the sub-optimal effectiveness of three doses of 720 EU in the rapidly accelerated schedule, if confirmed in future studies, might lead to a revision of the current schedule recommended for HIV-infected travellers.
authors.affiliation: Preventive Medicine and Epidemiology Unit, Hospital Clínic, Barcelona, Spain. guille.menapinilla@gmail.com
authors.forename: Guillermo
authors.initials: G
authors.lastname: Mena
authors.forename: Alberto L
authors.initials: AL
authors.lastname: García-Basteiro
authors.forename: Anna
authors.initials: A
authors.lastname: Llupià
authors.forename: Consolación
authors.initials: C
authors.lastname: Díez
authors.forename: Josep
authors.initials: J
authors.lastname: Costa
authors.forename: Josep-María
authors.initials: JM
authors.lastname: Gatell
authors.forename: Felipe
authors.initials: F
authors.lastname: García
authors.forename: José-María
authors.initials: JM
authors.lastname: Bayas
mesh_terms: D000328:Adult; D023241:Antiretroviral Therapy, Highly Active; D016516:CD4-CD8 Ratio; D060085:Coinfection; D005260:Female; D015658:HIV Infections / Q000150:complications / Q000276:immunology* / Q000821:virology; D006679:HIV Seropositivity / Q000150:complications; D006506:Hepatitis A / Q000517:prevention & control*; D022362:Hepatitis A Vaccines / Q000627:therapeutic use*; D006526:Hepatitis C / Q000150:complications; D006801:Humans; D056724:Immunity, Humoral; D007115:Immunization Schedule; D008297:Male; D012189:Retrospective Studies; D019562:Viral Load
chemical_list: D022362:Hepatitis A Vaccines
keywords: AVC; Adult Vaccination Centre; Associated factors; HAART; HAV; HIV; Hepatitis A vaccination; IDD; IDU; Immune response; Infectious Diseases Department; MSM; Rapidly accelerated schedule; hepatitis A virus; highly-active antiretroviral therapy; injection drug users; men who have sex with men