Journal Article > ResearchFull Text
PLOS One. 28 February 2013; Volume 8 (Issue 2); e57611.; DOI:10.1371/journal.pone.0057611
Estill J, Egger M, Johnson LF, Gsponer T, Wandeler G, et al.
PLOS One. 28 February 2013; Volume 8 (Issue 2); e57611.; DOI:10.1371/journal.pone.0057611
OBJECTIVES
Mortality in patients starting antiretroviral therapy (ART) is higher in Malawi and Zambia than in South Africa. We examined whether different monitoring of ART (viral load [VL] in South Africa and CD4 count in Malawi and Zambia) could explain this mortality difference.
DESIGN
Mathematical modelling study based on data from ART programmes.
METHODS
We used a stochastic simulation model to study the effect of VL monitoring on mortality over 5 years. In baseline scenario A all parameters were identical between strategies except for more timely and complete detection of treatment failure with VL monitoring. Additional scenarios introduced delays in switching to second-line ART (scenario B) or higher virologic failure rates (due to worse adherence) when monitoring was based on CD4 counts only (scenario C). Results are presented as relative risks (RR) with 95% prediction intervals and percent of observed mortality difference explained.
RESULTS
RRs comparing VL with CD4 cell count monitoring were 0.94 (0.74-1.03) in scenario A, 0.94 (0.77-1.02) with delayed switching (scenario B) and 0.80 (0.44-1.07) when assuming a 3-times higher rate of failure (scenario C). The observed mortality at 3 years was 10.9% in Malawi and Zambia and 8.6% in South Africa (absolute difference 2.3%). The percentage of the mortality difference explained by VL monitoring ranged from 4% (scenario A) to 32% (scenarios B and C combined, assuming a 3-times higher failure rate). Eleven percent was explained by non-HIV related mortality.
CONCLUSIONS
VL monitoring reduces mortality moderately when assuming improved adherence and decreased failure rates.
Mortality in patients starting antiretroviral therapy (ART) is higher in Malawi and Zambia than in South Africa. We examined whether different monitoring of ART (viral load [VL] in South Africa and CD4 count in Malawi and Zambia) could explain this mortality difference.
DESIGN
Mathematical modelling study based on data from ART programmes.
METHODS
We used a stochastic simulation model to study the effect of VL monitoring on mortality over 5 years. In baseline scenario A all parameters were identical between strategies except for more timely and complete detection of treatment failure with VL monitoring. Additional scenarios introduced delays in switching to second-line ART (scenario B) or higher virologic failure rates (due to worse adherence) when monitoring was based on CD4 counts only (scenario C). Results are presented as relative risks (RR) with 95% prediction intervals and percent of observed mortality difference explained.
RESULTS
RRs comparing VL with CD4 cell count monitoring were 0.94 (0.74-1.03) in scenario A, 0.94 (0.77-1.02) with delayed switching (scenario B) and 0.80 (0.44-1.07) when assuming a 3-times higher rate of failure (scenario C). The observed mortality at 3 years was 10.9% in Malawi and Zambia and 8.6% in South Africa (absolute difference 2.3%). The percentage of the mortality difference explained by VL monitoring ranged from 4% (scenario A) to 32% (scenarios B and C combined, assuming a 3-times higher failure rate). Eleven percent was explained by non-HIV related mortality.
CONCLUSIONS
VL monitoring reduces mortality moderately when assuming improved adherence and decreased failure rates.
Journal Article > ResearchFull Text
Pediatrics. 17 September 2012; Volume 130 (Issue 4); e966-e977.; DOI:10.1542/peds.2011-3020
Gsponer T, Weigel R, Davies MA, Bolton C, Moultrie H, et al.
Pediatrics. 17 September 2012; Volume 130 (Issue 4); e966-e977.; DOI:10.1542/peds.2011-3020
BACKGROUND
Poor growth is an indication for antiretroviral therapy (ART) and a criterion for treatment failure. We examined variability in growth response to ART in 12 programs in Malawi, Zambia, Zimbabwe, Mozambique, and South Africa.
METHODS
Treatment naïve children aged <10 years were included. We calculated weight for age z scores (WAZs), height for age z scores (HAZs), and weight for height z scores (WHZs) up to 3 years after starting ART, by using the World Health Organization standards. Multilevel regression models were used.
RESULTS
A total of 17 990 children (range, 238–8975) were followed for 36 181 person-years. At ART initiation, most children were underweight (50%) and stunted (66%). Lower baseline WAZ, HAZ, and WHZ were the most important determinants of faster catch-up growth on ART. WAZ and WHZ increased rapidly in the first year and stagnated or reversed thereafter, whereas HAZ increased continuously over time. Three years after starting ART, WAZ ranged from −2.80 (95% confidence interval [CI]: −3.66 to −2.02) to −1.98 (95% CI: −2.41 to −1.48) in children with a baseline z score < −3 and from −0.79 (95% CI: −1.62 to 0.02) to 0.05 (95% CI: −0.42 to 0.51) in children with a baseline WAZ ≥ −1. For HAZ, the corresponding range was −2.33 (95% CI: −2.62 to −2.02) to −1.27 (95% CI: −1.58 to −1.00) for baseline HAZ < −3 and −0.24 (95% CI: −0.56 to 0.15) to 0.84 (95% CI: 0.53 to 1.16) for HAZ ≥ −1.
CONCLUSIONS
Despite a sustained growth response and catch-up growth in children with advanced HIV disease treated with ART, normal weights and heights are not achieved over 3 years of ART.
Poor growth is an indication for antiretroviral therapy (ART) and a criterion for treatment failure. We examined variability in growth response to ART in 12 programs in Malawi, Zambia, Zimbabwe, Mozambique, and South Africa.
METHODS
Treatment naïve children aged <10 years were included. We calculated weight for age z scores (WAZs), height for age z scores (HAZs), and weight for height z scores (WHZs) up to 3 years after starting ART, by using the World Health Organization standards. Multilevel regression models were used.
RESULTS
A total of 17 990 children (range, 238–8975) were followed for 36 181 person-years. At ART initiation, most children were underweight (50%) and stunted (66%). Lower baseline WAZ, HAZ, and WHZ were the most important determinants of faster catch-up growth on ART. WAZ and WHZ increased rapidly in the first year and stagnated or reversed thereafter, whereas HAZ increased continuously over time. Three years after starting ART, WAZ ranged from −2.80 (95% confidence interval [CI]: −3.66 to −2.02) to −1.98 (95% CI: −2.41 to −1.48) in children with a baseline z score < −3 and from −0.79 (95% CI: −1.62 to 0.02) to 0.05 (95% CI: −0.42 to 0.51) in children with a baseline WAZ ≥ −1. For HAZ, the corresponding range was −2.33 (95% CI: −2.62 to −2.02) to −1.27 (95% CI: −1.58 to −1.00) for baseline HAZ < −3 and −0.24 (95% CI: −0.56 to 0.15) to 0.84 (95% CI: 0.53 to 1.16) for HAZ ≥ −1.
CONCLUSIONS
Despite a sustained growth response and catch-up growth in children with advanced HIV disease treated with ART, normal weights and heights are not achieved over 3 years of ART.
Journal Article > ResearchFull Text
AIDS. 1 September 2013; Volume 27 (Issue 14); 2225-32.; DOI:10.1097/QAD.0b013e328362d887
Wandeler G, Gsponer T, Mulenga L, Garone DB, Wood R, et al.
AIDS. 1 September 2013; Volume 27 (Issue 14); 2225-32.; DOI:10.1097/QAD.0b013e328362d887
OBJECTIVES
Zidovudine (ZDV) is recommended for first-line antiretroviral therapy (ART) in resource-limited settings. ZDV may, however, lead to anemia and impaired immunological response. We compared CD4+ cell counts over 5 years between patients starting ART with and without ZDV in southern Africa.
DESIGN
Cohort study.
METHODS
Patients aged at least 16 years who started first-line ART in South Africa, Botswana, Zambia, or Lesotho were included. We used linear mixed-effect models to compare CD4+ cell count trajectories between patients on ZDV-containing regimens and patients on other regimens, censoring follow-up at first treatment change. Impaired immunological recovery, defined as a CD4+ cell count below 100 cells/μl at 1 year, was assessed in logistic regression. Analyses were adjusted for baseline CD4+ cell count and hemoglobin level, age, sex, type of regimen, viral load monitoring, and calendar year.
RESULTS
A total of 72,597 patients starting ART, including 19,758 (27.2%) on ZDV, were analyzed. Patients on ZDV had higher CD4+ cell counts (150 vs.128 cells/μl) and hemoglobin level (12.0 vs. 11.0 g/dl) at baseline, and were less likely to be women than those on other regimens. Adjusted differences in CD4+ cell counts between regimens containing and not containing ZDV were -16 cells/μl [95% confidence interval (CI) -18 to -14] at 1 year and -56 cells/μl (95% CI -59 to -52) at 5 years. Impaired immunological recovery was more likely with ZDV compared to other regimens (odds ratio 1.40, 95% CI 1.22-1.61).
CONCLUSION
In southern Africa, ZDV is associated with inferior immunological recovery compared to other backbones. Replacing ZDV with another nucleoside reverse transcriptase inhibitor could avoid unnecessary switches to second-line ART.
Zidovudine (ZDV) is recommended for first-line antiretroviral therapy (ART) in resource-limited settings. ZDV may, however, lead to anemia and impaired immunological response. We compared CD4+ cell counts over 5 years between patients starting ART with and without ZDV in southern Africa.
DESIGN
Cohort study.
METHODS
Patients aged at least 16 years who started first-line ART in South Africa, Botswana, Zambia, or Lesotho were included. We used linear mixed-effect models to compare CD4+ cell count trajectories between patients on ZDV-containing regimens and patients on other regimens, censoring follow-up at first treatment change. Impaired immunological recovery, defined as a CD4+ cell count below 100 cells/μl at 1 year, was assessed in logistic regression. Analyses were adjusted for baseline CD4+ cell count and hemoglobin level, age, sex, type of regimen, viral load monitoring, and calendar year.
RESULTS
A total of 72,597 patients starting ART, including 19,758 (27.2%) on ZDV, were analyzed. Patients on ZDV had higher CD4+ cell counts (150 vs.128 cells/μl) and hemoglobin level (12.0 vs. 11.0 g/dl) at baseline, and were less likely to be women than those on other regimens. Adjusted differences in CD4+ cell counts between regimens containing and not containing ZDV were -16 cells/μl [95% confidence interval (CI) -18 to -14] at 1 year and -56 cells/μl (95% CI -59 to -52) at 5 years. Impaired immunological recovery was more likely with ZDV compared to other regimens (odds ratio 1.40, 95% CI 1.22-1.61).
CONCLUSION
In southern Africa, ZDV is associated with inferior immunological recovery compared to other backbones. Replacing ZDV with another nucleoside reverse transcriptase inhibitor could avoid unnecessary switches to second-line ART.
Journal Article > ResearchFull Text
AIDS. 20 March 2012; Volume 26 (Issue 11); DOI:10.1097/QAD.0b013e3283536988
Estill J, Aubriere C, Egger M, Johnson LF, Wood R, et al.
AIDS. 20 March 2012; Volume 26 (Issue 11); DOI:10.1097/QAD.0b013e3283536988
In low-income settings, treatment failure is often identified using CD4 cell count monitoring. Consequently, patients remain on a failing regimen, resulting in a higher risk of transmission. We investigated the benefit of routine viral load monitoring for reducing HIV transmission.