Differential impact of adherence on long-term treatment response among naive HIV-infected individuals

AIDS. 2008 Nov 12;22(17):2371-80. doi: 10.1097/QAD.0b013e328315cdd3.

Abstract

Objectives: To examine the long-term impact of adherence on virologic, immunologic, and dual response stratified by type of HAART regimen in treatment-naive patients starting HAART in British Columbia, Canada; and to assess the degree of virologic and immunologic response associated with emergence of drug resistance, progression to AIDS, and mortality.

Methods: Eligible participants initiated HAART between 1 January 2000 and 30 November 2004, were followed until 30 November 2005, and had at least 2 years of follow-up. Virologic and immunologic responses were dichotomized at their median values. Virologic response was defined as at least 65% of follow-up time with plasma viral load (pVL) of less than 50 copies/ml. Immunologic response was defined as a CD4 cell count increase of at least 145 cells/microl. Adherence measures were based on prescription refill compliance. Proportional odds models and logistic regression were used to address our objectives.

Results: The distribution of patient responses was 394 (44.9%) for CD4+/pVL+ (best), 350 (39.9%) for CD4-/pVL+ or CD4+/pVL- (incomplete), and 134 (15.3%) for CD4-/pVL- (worst). We found a positive correlation between adherence and virologic and immunologic responses (P < 0.01). Having worst compared with best response (reference group) was associated with higher odds of mortality (odds ratio: 6.09; 95% confidence interval: 2.57-14.42) and emergence of drug resistance (odds ratio: 10.56; 95% confidence interval: 5.93-18.81) even after adjusting for adherence and HAART regimen.

Conclusion: Patients not attaining the best virologic and immunologic responses are at a high risk for emergence of drug resistance and mortality, and these responses are highly dependent on the adherence level and initial HAART regimen. Patients on protease inhibitor-single did worse no matter the adherence level.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Anti-HIV Agents / therapeutic use*
  • Antiretroviral Therapy, Highly Active / methods*
  • British Columbia
  • CD4 Lymphocyte Count
  • Disease Progression
  • Drug Resistance, Viral / immunology*
  • Female
  • HIV Infections / drug therapy*
  • HIV Infections / immunology
  • HIV Infections / virology
  • HIV Protease Inhibitors / immunology
  • HIV Protease Inhibitors / therapeutic use*
  • HIV-1* / genetics
  • Humans
  • Male
  • Middle Aged
  • Patient Compliance
  • Practice Guidelines as Topic
  • Treatment Outcome
  • Viral Load

Substances

  • Anti-HIV Agents
  • HIV Protease Inhibitors