title: Revisiting long-term adherence to highly active antiretroviral therapy in Senegal using latent class analysis.
abstract: BACKGROUND
  Adherence is one of the main predictors of antiretroviral treatment success. A governmental initiative was launched in 1998 for HIV-infected patients in Senegal to provide access to highly active antiretroviral therapy.
  
  
  METHODS
  Between August 1998 and April 2002, 404 adult patients were enrolled. Adherence measurements, defined as pills taken/pills prescribed, were assessed between November 1999 and April 2009 using a pill count along with a questionnaire for 330 patients. Predictors of adherence were explored through a random-intercept Tobit model and a latent class analysis (LCA) was performed to identify adherence trajectories. We also performed a survival analysis taking into account gender and latent adherence classes.
  
  
  RESULTS
  Median treatment duration was 91 months (interquartile range, 84-101). On average, adherence declined by 7% every year, was 30% lower for patients taking indinavir, and 12% higher for those receiving cotrimoxazole prophylaxis. Based on the predicted probability of having an adherence ≥ 95%, LCA revealed 3 adherence behaviors and a better adherence for women. A quarter of patients had a high adherence trajectory over time and half had an intermediate one. Male gender and low adherence behavior over time were independently associated with a higher mortality rate.
  
  
  CONCLUSIONS
  This study shows that an overall good adherence can be obtained in the long term in Senegal. LCA suggests a better adherence for women and points out a large subsample of patients with intermediate level of adherence behavior who are at risk for developing resistance to antiretroviral drugs. This study warrants further research into gender issues.
authors.affiliation: Hospices Civils de Lyon, Service de Biostatistique, Lyon, France. mathieu.bastard@epicentre.msf.org
authors.forename: Mathieu
authors.initials: M
authors.lastname: Bastard
authors.forename: Mame Basty Koita
authors.initials: MB
authors.lastname: Fall
authors.forename: Isabelle
authors.initials: I
authors.lastname: Lanièce
authors.forename: Bernard
authors.initials: B
authors.lastname: Taverne
authors.forename: Alice
authors.initials: A
authors.lastname: Desclaux
authors.forename: René
authors.initials: R
authors.lastname: Ecochard
authors.forename: Papa Salif
authors.initials: PS
authors.lastname: Sow
authors.forename: Eric
authors.initials: E
authors.lastname: Delaporte
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Etard
mesh_terms: D000328:Adult; D019380:Anti-HIV Agents / Q000008:administration & dosage*; D023241:Antiretroviral Therapy, Highly Active / Q000379:methods* / Q000523:psychology / Q000592:standards; D018791:CD4 Lymphocyte Count; D015331:Cohort Studies; D005260:Female; D006678:HIV / Q000302:isolation & purification*; D015658:HIV Infections / Q000188:drug therapy* / Q000276:immunology / Q000523:psychology; D006801:Humans; D008297:Male; D010349:Patient Compliance; D012675:Senegal; D016019:Survival Analysis
chemical_list: D019380:Anti-HIV Agents