Rates and predictors of failure of first-line antiretroviral therapy and switch to second-line ART in South Africa.

Center for Global Health and Development, Boston University, 801 Massachusetts Ave., Boston, MA 02118, USA.
JAIDS Journal of Acquired Immune Deficiency Syndromes (Impact Factor: 4.39). 03/2012; 60(4):428-37. DOI: 10.1097/QAI.0b013e3182557785
Source: PubMed

ABSTRACT To measure rates and predictors of virologic failure and switch to second-line antiretroviral therapy (ART) in South Africa.
: Observational cohort study.
We included ART-naive adult patients initiated on public sector ART (January 2000 to July 2008) at 5 sites in South Africa who completed ≥6 months of follow-up. We estimated cumulative risk of virologic failure (viral load ≥400 copies/mL with confirmation above varying thresholds) and switching to second-line ART.
Nineteen thousand six hundred forty-five patients (29,935 person-years) had a median of 1.3 years of study follow-up (1.8 years on ART) and a median CD4 count of 93 (IQR: 39-155) cells per microliter at ART initiation. About 9.9% (4.5 per 100 person-years) failed ART in median 16 (IQR: 12-23) months since ART initiation, with median 2.7 months (IQR: 1.6-4.7) months between first elevated and confirmatory viral loads. By survival analysis, using a confirmatory threshold of 400 copies per milliliter, 16.9% [95% confidence interval (CI): 15.4% to 18.6%] failed by 5 years on ART, but only 7.8% (95% CI: 6.6% to 9.3%) using a threshold of 10,000. CD4 <25 versus 100-199 (adjusted HR: 1.60; 95% CI: 1.37 to 1.87), ART initiation viral load ≥1,000,000 versus <10,000, (1.32; 0.91 to 1.93), and 2+ gaps in care versus 0 (95% CI: 7.25; 4.95 to 10.6) were predictive of failure. Overall, 10.1% (95% CI: 9.0% to 11.4%) switched to second-line by 5 years on ART. Lower CD4 at failure and higher rate of CD4 decline were predictive of switch (decline 100% to 51% versus 25% to -25%, adjusted HR: 1.96; 95% CI: 1.35 to 2.85).
In resource-limited settings with viral load monitoring, virologic failure rates are highly sensitive to thresholds for confirmation. Despite clear guidelines there is considerable variability in switching failing patients, partially in response to immunologic status and postfailure evolution.

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: This study explores factors associated with virological detectability, and viral re-suppression after enhanced adherence counselling, in adults and children on antiretroviral therapy (ART) in Swaziland. This descriptive study used laboratory data from 7/5/2012 to 30/9/2013, which were linked with the national ART database to provide information on time on ART and CD4 count; information on enhanced adherence counselling was obtained from file review in health facilities. Multivariable logistic regression was used to explore the relationship between viral load, gender, age, time on ART, CD4 count and receiving (or not receiving) enhanced adherence counselling. From 12,063 patients undergoing routine viral load monitoring, 1941 (16%) had detectable viral loads. Children were more likely to have detectable viral loads (AOR 2.6, 95%CI 1.5-4.5), as were adolescents (AOR 3.2, 95%CI 2.2-4.8), patients with last CD4<350 cells/µl (AOR 2.2, 95%CI 1.7-2.9) or WHO Stage 3/4 disease (AOR 1.3, 95%CI 1.1-1.6), and patients on ART for longer (AOR 1.1, 95%CI 1.1-1.2). At retesting, 450 (54% of those tested) showed viral re-suppression. Children were less likely to re-suppress (AOR 0.2, 95%CI 0.1-0.7), as were adolescents (AOR 0.3, 95%CI 0.2-0.8), those with initial viral load> 1000 copies/ml (AOR 0.3, 95%CI 0.1-0.7), and those with last CD4<350 cells/µl (AOR 0.4, 95%CI 0.2-0.7). Receiving (or not receiving) enhanced adherence counselling was not associated with likelihood of re-suppression. Children, adolescents and those with advanced disease were most likely to have high viral loads and least likely to achieve viral suppression at retesting; receiving adherence counselling was not associated with higher likelihood of viral suppression. Although the level of viral resistance was not quantified, this study suggests the need for ART treatment support that addresses the adherence problems of younger people; and to define the elements of optimal enhanced adherence support for patients of all ages with detectable viral loads.
    PLoS ONE 02/2015; 10(2):e0116144. DOI:10.1371/journal.pone.0116144 · 3.53 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: We sought to examine which socioeconomic indicators are risk factors for virologic failure among HIV-1 infected patients receiving antiretroviral therapy (ART) in KwaZulu-Natal, South Africa. A case-control study of virologic failure was conducted among patients recruited from the outpatient clinic at McCord Hospital in Durban, South Africa between October 1, 2010 and June 30, 2012. Cases were those failing first-line ART, defined as viral load >1,000 copies/mL. Univariate logistic regression was performed on sociodemographic data for the outcome of virologic failure. Variables found significant (p < 0.05) were used in multivariate models and all models were stratified by gender. Of 158 cases and 300 controls, 35 % were male and median age was 40 years. Gender stratification of models revealed automobile ownership was a risk factor among males, while variables of financial insecurity (unemployment, non-spouse family paying for care, staying with family) were risk factors for women. In this cohort, financial insecurity among women and automobile ownership among men were risk factors for virologic failure. Risk factor differences between genders demonstrate limitations of generalized risk factor analysis.
    AIDS and Behavior 07/2014; 18(11). DOI:10.1007/s10461-014-0849-1 · 3.49 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Background While Brazil has had a long-standing policy of free access to antiretroviral therapy (ART) for all in need, the epidemiological impact of ART on human immunodeficiency virus (HIV) RNA suppression in this middle-income country has not been well evaluated. We estimate first-line ART effectiveness in a large Brazilian cohort and examine the socio-demographic, behavioral, clinical and structural factors associated with virologic suppression. Methods Virologic suppression on first-line ART at 6, 12, and 24 months from start of ART was defined as having a viral load measurement ≤400 copies/mL without drug class modification and/or discontinuation. Drug class modification and/or discontinuation were defined based on the class of a particular drug. Quasi-Poisson regression was used to quantify the association of factors with virologic suppression. Results From January 2000 through June 2010, 1311 patients started first-line ART; 987 (75%) patients used NNRTI-based regimens. Virologic suppression was achieved by 77%, 76% and 68% of patients at 6, 12 and 24 months, respectively. Factors associated with virologic suppression at 12 months were: >8 years of formal education (compared to <4 years, risk ratio (RR) 1.13, 95% confidence interval (95% CI) 1.03-1.24), starting ART in 2005-2010 (compared to 2000-2004, RR 1.25 95% CI 1.15-1.35), and clinical trial participation (compared to no participation, RR 1.08 95% CI 1.01-1.16). Also at 12 months, women showed less virologic suppression compared to heterosexual men (RR 0.90 95% CI 0.82-0.99). For the 24-month endpoint, in addition to higher education, starting ART in the later period, and clinical trial participation, older age and an NNRTI-based regimen were also independently associated with virologic suppression. Conclusions Our results show that in Brazil, a middle-income country with free access to treatment, over three-quarters of patients receiving routine care reached virologic suppression on first-line ART by the end of the first year. Higher education, more recent ART initiation and clinical trial participation were associated with improved outcomes both for the 12-month and the 24-month endpoints, suggesting that further studies are needed to understand what aspects relating to these factors lead to higher virologic suppression.
    AIDS Research and Therapy 09/2014; 11:29. DOI:10.1186/1742-6405-11-29 · 1.84 Impact Factor