title: The impact of first year adherence to antiretroviral therapy on long-term clinical and immunological outcomes in the DART trial in Uganda and Zimbabwe.
abstract: OBJECTIVE
  To describe associations between different summaries of adherence in the first year on antiretroviral therapy (ART) and the subsequent risk of mortality, to identify patients at high risk because of early adherence behaviour.
  
  
  METHODS
  We previously described an approach where adherence behaviour at successive clinic visits during the first year on ART was seen as a Markov chain (MC), and the individually estimated transition probabilities between 'good', 'poor' and 'non-response' adherence states were used to classify HIV-infected adults in the DART trial into subgroups with similar behaviour. The impact of this classification and classifications based on traditional 'averaged' measures [mean drug possession ratio (DPR) and self-reported adherence] were compared in terms of their impact on longer-term mortality over the 2-5 years on ART using Cox proportional hazards models.
  
  
  RESULTS
  Of 2960 participants in follow-up after 1 year on ART, 29% had never missed pills in the last month and 11% had 100% DPR throughout the first year. The poorest adherers by self-reported measures were more likely to have only none/primary education (P < 0.01). Being in the poorest adherence subgroup by MC and DPR was independently associated with increased mortality [HR = 1.57 (95% CI 1.02, 2.42); 1.82 (1.32, 2.51) respectively].
  
  
  CONCLUSIONS
  Classification based on dynamic adherence behaviour is associated with mortality independently of DPR. The classifications could be useful in understanding adherence, targeting focused interventions and improving longer-term adherence to therapy.
authors.affiliation: School of Health Sciences, University of Tampere, Finland. skiwuwa@yahoo.com
authors.forename: S
authors.initials: S
authors.lastname: Kiwuwa-Muyingo
authors.forename: A S
authors.initials: AS
authors.lastname: Walker
authors.forename: H
authors.initials: H
authors.lastname: Oja
authors.forename: J
authors.initials: J
authors.lastname: Levin
authors.forename: G
authors.initials: G
authors.lastname: Miiro
authors.forename: E
authors.initials: E
authors.lastname: Katabira
authors.forename: C
authors.initials: C
authors.lastname: Kityo
authors.forename: J
authors.initials: J
authors.lastname: Hakim
authors.forename: J
authors.initials: J
authors.lastname: Todd
mesh_terms: D000328:Adult; D019380:Anti-HIV Agents / Q000627:therapeutic use*; D023241:Antiretroviral Therapy, Highly Active / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D015658:HIV Infections / Q000188:drug therapy* / Q000276:immunology; D006801:Humans; D008297:Male; D008390:Markov Chains; D010349:Patient Compliance / Q000706:statistics & numerical data*; D016016:Proportional Hazards Models; D011795:Surveys and Questionnaires; D016896:Treatment Outcome; D014454:Uganda; D015030:Zimbabwe
chemical_list: D019380:Anti-HIV Agents