Initiating highly active antiretroviral therapy in sub-Saharan Africa: an assessment of the revised World Health Organization scaling-up guidelines

Diagnosis of Human Immunodeficiency Virus Infection

HIV diagnostics have played a central role in the remarkable progress in identifying, staging, initiating, and monitoring infected individuals on life-saving antiretroviral therapy. They are also useful in surveillance and outbreak responses, allowing for assessment of disease burden and identification of vulnerable populations and transmission "hot spots," thus enabling planning, appropriate interventions, and allocation of appropriate funding. HIV diagnostics are critical in achieving epidemic control and require a hybrid of conventional laboratory-based diagnostic tests and new technologies, including point-of-care (POC) testing, to expand coverage, increase access, and positively impact patient management. In this review, we provide (i) a historical perspective on the evolution of HIV diagnostics (serologic and molecular) and their interplay with WHO normative guidelines, (ii) a description of the role of conventional and POC testing within the tiered laboratory diagnostic network, (iii) information on the evaluations and selection of appropriate diagnostics, (iv) a description of the quality management systems needed to ensure reliability of testing, and (v) strategies to increase access while reducing the time to return results to patients. Maintaining the central role of HIV diagnostics in programs requires periodic monitoring and optimization with quality assurance in order to inform adjustments or alignment to achieve epidemic control.

Predictors of Survival among Adult Ethiopian Patients in the National ART Program at Seven University Teaching Hospitals: A Prospective Cohort Study

Background

In Ethiopia, the publicly funded antiretroviral treatment (ART) program was started in 2005. Two hundred seventy-five thousand patients were enrolled in the national ART program by 2012. However, there is limited data on mortality and predictors of death among adult patients in the ART program. The study aimed to estimate mortality and risk factors for death among adult, ART-naïve patients, started in the national ART program from January 2009 to July 2013.

Methods

Multi-site, prospective, observational cohort study of adult, age > 18 years, ART-naïve patients, started in the national ART program at seven university-affiliated hospitals from January 2009 – July 2013. Kaplan-Meier and Cox regression analyses were used to estimate survival and determine risk factors for death.

Results

A total of 976 patients, 594 females (60.9 %), were enrolled into the study. Median age of the cohort was 33years. The median CD4 count at start of ART was 144 cells/µl (interquartile range (IQR) 78–205), and 34.2% (330/965) had CD4 < 100. Sixty-three percent (536/851) had viral load greater than 5 log copies/ml (IQR 4.7–5.7) at base line. One hundred and one deaths were recorded during follow-up period, all-cause mortality rate 10.3%; 5.4 deaths/100 person years of observation, 95% confidence interval 4.4–6.5. Seventy percent of the deaths occurred within six months of starting ART. Cox regression analyses showed that the following measures independently predicted mortality: age >51 years, (Adjusted Hazard Ratio (AHR) 4.01, P=0.003), WHO stages III&IV, (AHR 1.76, p = 0.025), CD4 count, <100, (AHR 2.36, p =0.006), and viral load >5 log copies /ml (CHR 1.71, p = 0.037).

Conclusion

There is high early on- ART mortality in patients presenting with advanced immunodeficiency. Detecting cases and initiating ART before onset of advanced immunodeficiency might improve survival.

Cost-effectiveness analysis of the national decentralization policy of antiretroviral treatment programme in Zambia

Background

In resource-limited settings with a high prevalence of human immunodeficiency virus (HIV) infection such as Zambia, decentralization of HIV/acquired immunodeficiency syndrome (HIV/AIDS) treatment and care with effective use of resources is a cornerstone of universal treatment and care.

Objectives

This research aims to analyse the cost effectiveness of the National Mobile Antiretroviral Therapy (ART) Services Programme in Zambia as a means of decentralizing ART services.

Methods

Cost-effectiveness analyses were performed using a decision analytic model and Markov model to compare the original ART programme, ‘Hospital-based ART’, with the intervention programme, Hospital-based plus ‘Mobile ART’, from the perspective of the district government health office in Zambia. The total cost of ART services, quality-adjusted life years (QALYs) and incremental cost-effectiveness ratios (ICERs) were examined.

Results

The mean annual per-patient costs were 1259.16 USD for the original programme and 2601.02 USD for the intervention programme, while the mean number of QALYs was 6.81 for the original and 7.27 for the intervention programme. The ICER of the intervention programme relative to the original programme was 2965.17 USD/QALY, which was much below the willingness-to-pay (WTP), or three times the GDP per capita (4224 USD), but still over the GDP per capita (1408 USD). In the sensitivity analysis, the ICER of the intervention programme did not substantially change.

Conclusion

The National Mobile ART Services Programme in Zambia could be a cost-effective approach to decentralizing ART services into rural areas in Zambia. This programme could be expanded to more districts where it has not yet been introduced to improve access to ART services and the health of people living with HIV (PLHIV) in rural areas.

Electronic supplementary material

The online version of this article (doi:10.1186/s12962-017-0065-8) contains supplementary material, which is available to authorized users.

Home testing and counselling to reduce HIV incidence in a generalised epidemic setting: a mathematical modelling analysis

BACKGROUND

Home HIV testing and counselling (HTC) achieves high levels of HIV testing and linkage to care. Periodic home HTC, particularly targeted to those with high HIV viral load, might facilitate expansion of antiretroviral therapy (ART) coverage. We used a mathematical model to assess the effect of periodic home HTC programmes on HIV incidence in KwaZulu-Natal, South Africa.

METHODS

We developed a dynamic HIV transmission model with parameters, primary cost data, and measures of viral suppression collected from a prospective study of home HTC in KwaZulu-Natal. In our model, we assumed home HTC took place every 5 years with ART initiation for people with CD4 counts of 350 cells per μL or less. For individuals with CD4 counts of more than 350 cells per μL, we compared increasing ART coverage for those with 350-500 cells per μL with initiating treatment for those who have viral loads of more than 10 000 copies per mL.

FINDINGS

Maintaining the presently observed level of 36% viral suppression in HIV-positive people, HIV incidence decreases by 33·8% over 10 years. Home HTC every 5 years with linkage to care with ART initiation at CD4 counts of 350 cells per μL or less reduces HIV incidence by 40·6% over 10 years. Expansion of ART to people with CD4 counts of more than 350 cells per μL who also have a viral load of 10 000 copies per mL or more decreases HIV incidence by 51·6%, and this was the most cost-effective strategy for prevention of HIV infections at US$2960 per infection averted. Expansion of ART eligibility CD4 counts of 350-500 cells per μL is cost-effective at $900 per quality-adjusted life-year gained. Following health economic guidelines, expansion of ART use to individuals who have viral loads of more than 10 000 copies per mL among those with CD4 counts of more than 350 cells per μL was cost-effective to reduce HIV-related morbidity.

INTERPRETATION

Our results show that province-wide home HTC every 5 years can be a cost-effective strategy to increase ART coverage and reduce HIV burden. Expanded ART initiation criteria that includes individuals with high viral load will improve the effectiveness of home HTC in linking individuals to ART who are at high risk of transmitting HIV, thereby preventing morbidity and onward transmission.

FUNDING

National Institutes of Health.

Delay Between First HIV-Related Symptoms and Diagnosis of HIV Infection in Patients Attending the Internal Medicine Department of the Fondation Jeanne Ebori (FJE), Libreville, Gabon

BACKGROUND

HIV-infected patients (pts) in Africa are often diagnosed at very advanced stages of disease. They seek relief using traditional medicine or religious beliefs. General practitioners (GPs) are often consulted first. Once the HIV diagnosis has been made, concomitant use of alternative and allopathic medicine is also frequent.

OBJECTIVE

To describe the delay between presentation of HIV-related symptoms and diagnosis, the first physician consulted, and the use of traditional medicine or religion as an alternative or complement to allopathic medicine in HIV-infected patients.

METHOD

Patients followed for HIV infection at Fondation Jeanne Ebori were retrospectively interviewed to trace their therapeutic itinerary.

RESULTS

150 pts were interviewed. There were 63% females, mean age was 39 years, median CD4 count was 242 cells/microL (102-394), CDC stage A/B/C was 32%/40%/28%, and 57% had very low income. Religious affiliations were Catholic (52%), Protestant (21%), Muslim (3%), "progressive" Church (16%), and none (7%). The median time elapsed between their first symptoms and HIV diagnosis was 124 (20-292) days. The first person consulted was a traditional healer (5%), GP (61%), or private clinics (23%). Traditional healers were consulted for initiation rites in 23%, cure of disease in 90%, or sorcery in 20%. Once allopathic medicine was started, concomitant alternative therapy occurred in 25 (17%) for traditional medicine and 4 (3%) for faith healing. Resort to traditional healer (odds ratio [OR] 2.6, p = .02) and to faith healing (OR 3.1, p = .048) were risk factors for diagnosis delay.

CONCLUSION

Many factors related to patients, the health system, and culture or society are detrimental to an early diagnosis of HIV infection in Gabon. Increasing awareness of the risk of HIV infection throughout the general population and hope and trust in western medicine in patients and non-HIV-specialist physicians, as well as suppression of social stigma, could shorten the delay before diagnosis. Better communication between allopathic physicians and traditional or faith healers could also improve the care of HIV-infected patients.

Early initiation of antiretroviral therapy in HIV-infected adults and adolescents: a systematic review

OBJECTIVES

The objective of this review was to update evidence on when to initiate antiretroviral therapy (ART) to inform revision of the 2013 WHO guidelines for ART in low and middle-income countries.

DESIGN

A systematic review and meta-analysis.

METHODS

We comprehensively searchescohorts. Outcomes were mortality, clinical progression, virologic failure, immunologic recover, and severe adverse events. We pooled data across studies and estimated summary effect sizes. We graded the quality of evidence from the literature for each outcome.

RESULTS

We identified 24 studies; 3 were RCTs. Studies found reduced risk of mortality [1 RCT: hazard ratio 0.77, 95% confidence interval (CI) 0.34-1.76; 13 cohorts: relative risk (RR) 0.66, 95% CI 0.55-0.79], progression to AIDS or death (2 RCTs: RR 0.48, 95% CI 0.26-0.91; 9 cohorts: RR 0.70, 95% CI 0.40-1.24) and diagnosis of a non-AIDS-defining illness (1 RCT: RR 0.14, 95% CI 0.03-0.64; 1 cohort: RR 0.47, 95% CI 0.23-0.98), and an increased risk of grade 3/4 laboratory abnormalities in patients initiating ART at at least 350 cells/μl (1 RCT: RR 1.49, 95% CI 1.25-1.77). The quality of evidence was low or very low for clinical outcomes due to few events and imprecision, and high for adverse events.

CONCLUSIONS

Our findings contributed to the evidence base for the revised 2013 WHO guidelines on ART, which recommend initiating ART at CD4 T-cell counts of 350-500 cells/μl, but not above 500 cells/μl compared to initiating it later when CD4 T-cell counts fall below 350 cells/μl.

No association of cryptococcal antigenemia with poor outcomes among antiretroviral therapy-experienced HIV-infected patients in Addis Ababa, Ethiopia

Introduction

There are limited data on clinical outcomes of ART-experienced patients with cryptococcal antigenemia. We assessed clinical outcomes of a predominantly asymptomatic, ART-experienced cohort of HIV+ patients previously found to have a high (8.4%) prevalence of cryptococcal antigenemia.

Methods

The study took place at All Africa Leprosy, Tuberculosis and Rehabilitative Training Centre and Black Lion Hospital HIV Clinics in Addis Ababa, Ethiopia. A retrospective study design was used to perform 12-month follow-up of 367 mostly asymptomatic HIV-infected patients (CD4<200 cells/µl) with high levels of antiretroviral therapy use (74%) who were previously screened for cryptococcal antigenemia. Medical chart abstraction was performed approximately one year after initial screening to obtain data on clinic visit history, ART use, CD4 count, opportunistic infections, and patient outcome. We evaluated the association of cryptococcal antigenemia and a composite poor outcome of death and loss to follow-up using logistic regression.

Results

Overall, 323 (88%) patients were alive, 8 (2%) dead, and 36 (10%) lost to follow-up. Among the 31 patients with a positive cryptococcal antigen test (titers ≥1∶8) at baseline, 28 were alive (all titers ≤1∶512), 1 dead and 2 lost to follow-up (titers ≥1∶1024). In multivariate analysis, cryptococcal antigenemia was not predictive of a poor outcome (aOR = 1.3, 95% CI 0.3–4.8). A baseline CD4 count <100 cells/µl was associated with an increased risk of a poor outcome (aOR 3.0, 95% CI 1.4–6.7) while an increasing CD4 count (aOR 0.1, 95% CI 0.1–0.3) and receiving antiretroviral therapy at last follow-up visit (aOR 0.1, 95% CI 0.02–0.2) were associated with a reduced risk of a poor outcome.

Conclusions

Unlike prior ART-naïve cohorts, we found that among persons receiving ART and with CD4 counts <200 cells/µl, asymptomatic cryptococcal antigenemia was not predictive of a poor outcome.

Estimation of HIV-testing rates to maximize early diagnosis-derived benefits at the individual and population level

Background

In HIV infection, initiation of treatment is associated with improved clinical outcom and reduced rate of sexual transmission. However, difficulty in detecting infection in early stages impairs those benefits. We determined the minimum testing rate that maximizes benefits derived from early diagnosis.

Methods

We developed a mathematical model of HIV infection, diagnosis and treatment that allows studying both diagnosed and undiagnosed populations, as well as determining the impact of modifying time to diagnosis and testing rates. The model’s external consistency was assessed by estimating time to AIDS and death in absence of treatment as well as by estimating age-dependent mortality rates during treatment, and comparing them with data previously reported from CASCADE and DHCS cohorts.

Results

In our model, life expectancy of patients diagnosed before 8 years post infection is the same as HIV-negative population. After this time point, age at death is significantly dependent on diagnosis delay but initiation of treatment increases life expectancy to similar levels as HIV-negative population. Early mortality during HAART is dependent on treatment CD4 threshold until 6 years post infection and becomes dependent on diagnosis delay after 6 years post infection. By modifying testing rates, we estimate that an annual testing rate of 20% leads to diagnosis of 90% of infected individuals within the first 8.2 years of infection and that current testing rate in middle-high income settings stands close to 10%. In addition, many differences between low-income and middle-high incomes can be predicted by solely modifying the diagnosis delay.

Conclusions

To increase testing rate of undiagnosed HIV population by two-fold in middle-high income settings will minimize early mortality during initiation of treatment and global mortality rate as well as maximize life expectancy. Our results highlight the impact of achieving early diagnosis and the importance of strongly work on improving HIV testing rates.

[Dynamic of respiratory pathology in a service of pneumology in black Africa in the context of HIV infection from 1998 to 2007]

INTRODUCTION

The pneumology in developing countries is practiced in a singular context: population mostly younger, endemic tuberculosis, high prevalence of HIV infection and growing pollution.

OBJECTIVE

The aim of this study is to present respiratory pathology evolution in hospitalization of pneumology department in black Africa.

METHODOLOGY

Our study is retrospective and descriptive. We consulted the register of hospitalization activities from January 1998 to December 2007.

RESULTS

The age group of 20-49 years represents 78.36% of all patients. Tuberculosis (TB) remains the first affection from 1998 to 2007 with a frequency varying between 38.2% and 45.2%. The cases of pneumonia are in regression since 2001, but cases of febrile alveolar interstitial pneumonia (FAIP) increase. The pathologies bound to tobacco addiction are rare. HIV infection is associated to TB (82.86%), to pneumonia (77.22%), to FAIP (92.23%). On 832 cases of death recorded, 46.15% of deaths are assigned to TB, 15.98% to pneumonia and 14.66% to FAIP. The global lethality of the TB and the pneumonia is respectively 20.1% and 17.6%. The one of FAIP is 32.5%. Mortality attributable to TB and pneumonia decreases progressively but the one attributable to FAIP remains important.

CONCLUSION

Respiratory pathology is dominated by TB, pneumonia and FAIP. These pathologies associated to HIV infection cause a strong mortality.

A randomized trial of punctuated antiretroviral therapy in Ugandan HIV-seropositive adults with pulmonary tuberculosis and CD4⁺ T-cell counts of ≥ 350 cells/μL

BACKGROUND

Optimal treatment of human immunodeficiency virus (HIV)-associated tuberculosis in patients with high CD4⁺ T-cell counts is unknown. Suppression of viral replication during therapy for tuberculosis may block effects of immune activation on T cells and slow HIV disease progression.

METHODS

We conducted a randomized trial in 214 HIV-infected patients with active tuberculosis and CD4⁺ T-cell counts of ≥ 350 cells/μL to determine whether 6 months of antiretroviral therapy given during tuberculosis treatment would improve clinical outcomes. Subjects were randomized to receive 6 months of abacavir-lamivudine-zidovudine concurrent with tuberculosis therapy or delayed antiretroviral therapy. Endpoints were CD4⁺ T-cell counts of < 250 cells/μL, AIDS, or death.

RESULTS

Intervention and comparison arms had similar median CD4⁺ counts (517 and 534 cells/μL, respectively) and HIV RNA levels (4.6 and 4.7 log₁₀ copies/μL, respectively). Viral suppression was achieved in 86% of patients allocated to intervention. Seventeen subjects (15.6%) in the intervention arm developed study outcome compared to 25 subjects (22.8%) in the comparison arm (P = .17). Grade 3 or 4 adverse events were less frequent in the intervention arm. By 2 months, 90% of subjects in both arms were culture-negative for tuberculosis.

CONCLUSIONS

Short-term antiretroviral therapy during tuberculosis treatment in patients with CD4⁺T-cell counts of >350 cells/μL was safe and associated with clinical benefits.

Normal Range of CD4 Cell Counts and Temporal Changes in Two HIVNegative Malawian Populations

Longitudinal studies were carried out to determine trends in CD4 cell counts over a four year period in healthy HIV-negative adults in a rural (134 individuals) and an urban (80 individuals) site in Malawi, using TruCountTM and FACScountTM platforms. At baseline, median counts and 95% ranges were 890 (359-1954) cells per microlitre (μl) and 725 (114-1074) cells/μl respectively. 1.5% and 6% respectively had baseline counts below 350 cells/μl and 1.5% and 2.5% below 250 cells per μl. Transient dips to below 250 cells/μl were observed in seven individuals, with two individuals having persistently low CD4 counts over more than one year. Women and individuals from the urban site were significantly more likely to have "low CD4 count" (< 500 cells/μl) even when adjusted for other factors. In common with neighbouring countries, HIV-negative populations in Malawi have CD4 counts considerably lower than European reference ranges, and healthy individuals may have persistently or transiently low counts. Within Malawi, ranges differ according to the selected population.

Why reinvent the wheel? Leveraging the lessons of HIV scale-up to confront non-communicable diseases

The dramatic scale-up of HIV services in lower-income countries has led to the development of service delivery models reflecting the specific characteristics of HIV and its treatment as well as local contexts and cultures. Given the shared barriers and challenges faced by health programmes in lower-income countries, many of the implementation approaches developed for HIV programmes have the potential to contribute to the continuity care framework needed to address non-communicable diseases (NCDs) in resource-limited settings. HIV programmes are, in fact, the first large-scale chronic disease programmes in many countries, offering local and effective tools, models and approaches that can be replicated, adapted and expanded. As such, they might be used to 'jumpstart' the development of initiatives to provide prevention, care and treatment services for NCDs and other chronic conditions.

Validation of World Health Organisation HIV/AIDS clinical staging in predicting initiation of antiretroviral therapy and clinical predictors of low CD4 cell count in Uganda

Introduction

The WHO clinical guidelines for HIV/AIDS are widely used in resource limited settings to represent the gold standard of CD4 counts for antiviral therapy initiation. The utility of the WHO-defined stage 1 and 2 clinical factors used in WHO HIV/AIDS clinical staging in predicting low CD4 cell count has not been established in Uganda. Although the WHO staging has shown low sensitivity for predicting CD4<200cells/mm³, it has not been evaluated at for CD4 cut-offs of <250cells/mm³ or <350 cells/mm³.

Objective

To validate the World Health Organisation HIV/AIDS clinical staging in predicting initiation of antiretroviral therapy in a low-resource setting and to determine the clinical predictors of low CD4 cell count in Uganda.

Results

Data was collected on 395 participants from the Joint Clinical Research Centre, of whom 242 (61.3%) were classified as in stages 1 and 2 and 262 (68%) were females. Participants had a mean age of 36.8 years (SD 8.5). We found a significant inverse correlation between the CD4 lymphocyte count and WHO clinical stages. The sensitivity the WHO clinical staging at CD4 cell count of 250 cells/mm³ and 350cells/mm³ was 53.5% and 49.1% respectively. Angular cheilitis, papular pruritic eruptions and recurrent upper respiratory tract infections were found to be significant predictors of low CD4 cell count among participants in WHO stage 1 and 2.

Conclusion

The WHO HIV/AIDS clinical staging guidelines have a low sensitivity and about half of the participants in stages 1 and 2 would be eligible for ART initiation if they had been tested for CD4 count. Angular cheilitis and papular pruritic eruptions and recurrent upper respiratory tract infections may be used, in addition to the WHO staging, to improve sensitivity in the interim, as access to CD4 machines increases in Uganda.

Equity and efficiency in HIV-treatment in South Africa: the contribution of mathematical programming to priority setting

The HIV-epidemic is one of the greatest public health crises to face South Africa. A health care response to the treatment needs of HIV-positive people is a prime example of the desirability of an economic, rational approach to resource allocation in the face of scarcity. Despite this, almost no input based on economic analysis is currently used in national strategic planning. While cost-utility analysis is theoretically able to establish technical efficiency, in practice this is accomplished by comparing an intervention's ICER to a threshold level representing society's maximum willingness to pay to avoid death and improve health-related quality of life. Such an approach has been criticised for a number of reasons, including that it is inconsistent with a fixed budget for health care and that equity is not taken into account. It is also impractical if no national policy on the threshold exists. As an alternative, this paper proposes a mathematical programming approach that is capable of highlighting technical efficiency, equity, the equity/efficiency trade-off and the affordability of alternative HIV-treatment interventions. Government could use this information to plan an HIV-treatment strategy that best meets equity and efficiency objectives within budget constraints.

Economic evaluation of ART in resource-limited countries

PURPOSE OF REVIEW

In the face of increasing economic constraints, it is critically important to evaluate how best to utilize available resources. In this article, we review the growing number of cost-effectiveness analyses of HIV treatment with antiretroviral therapy (ART) in resource-limited settings. We focus on studies that evaluate when to start therapy, what therapy to start with and what to switch to based on what criteria.

RECENT FINDINGS

Recent findings show that earlier ART initiation based on CD4 cell count criteria (CD4 cell counts <350 cells/microl) can be cost effective in most resource-limited settings. They also suggest that initiating ART with tenofovir as a component of the first-line regimen is an efficient use of resources compared with initiating ART with stavudine. Finally, they show that HIV RNA monitoring combined with CD4 monitoring is more effective than CD4 monitoring alone, although this strategy was not yet found to be cost effective in all studies. Nearly all studies demonstrate, however, that the cost-effectiveness ratio of HIV RNA monitoring will become more attractive as the cost of HIV RNA tests and second-line ART regimens decrease.

SUMMARY

Substantial research shows that ART for HIV disease in resource-limited settings is cost effective. Improved initial regimens and increased laboratory monitoring may provide both clinical benefit and good value for money. Further price reductions of laboratory tests and recent antiretroviral drugs are needed to guarantee the cost-effectiveness of these required improvements.

Additive contribution of HLA class I alleles in the immune control of HIV-1 infection

Previous studies have identified a central role for HLA-B alleles in influencing control of HIV infection. An alternative possibility is that a small number of HLA-B alleles may have a very strong impact on HIV disease outcome, dominating the contribution of other HLA alleles. Here, we find that even following the exclusion of subjects expressing any of the HLA-B class I alleles (B*57, B*58, and B*18) identified to have the strongest influence on control, the dominant impact of HLA-B alleles on virus set point and absolute CD4 count variation remains significant. However, we also find that the influence of HLA on HIV control in this C-clade-infected cohort from South Africa extends beyond HLA-B as HLA-Cw type remains a significant predictor of virus and CD4 count following exclusion of the strongest HLA-B associations. Furthermore, there is evidence of interdependent protective effects of the HLA-Cw*0401-B*8101, HLA-Cw*1203-B*3910, and HLA-A*7401-B*5703 haplotypes that cannot be explained solely by linkage to a protective HLA-B allele. Analysis of individuals expressing both protective and detrimental alleles shows that even the strongest HLA alleles appear to have an additive rather than dominant effect on HIV control at the individual level. Finally, weak but significant frequency-dependent effects in this cohort can be detected only by looking at an individual's combined HLA allele frequencies. Taken together, these data suggest that although individual HLA alleles, particularly HLA-B, can have a strong impact, HIV control overall is likely to be influenced by the additive effect of some or all of the other HLA alleles present.

Optimal time for initiation of antiretroviral therapy in asymptomatic, HIV-infected, treatment-naive adults

BACKGROUND

According to consensus, initiation of therapy is best based on CD4 cell count, a marker of immune status, rather than on viral load, a marker of virologic replication. For patients with advanced symptoms, treatment should be started regardless of CD4 count. However, the point during the course of HIV infection at which antiretroviral therapy (ART) is best initiated in asymptomatic patients remains unclear. Guidelines issued by various agencies provide different initiation recommendations according to resource availability. This can be confusing for clinicians and policy-makers when determining the best time to initiate therapy. Optimizing the initiation of ART is clearly complex and must, therefore, be balanced between individual and broader public health needs.

OBJECTIVES

To assess the evidence for the optimal time to initiate ART in treatment-naive, asymptomatic, HIV-infected adults

SEARCH STRATEGY

We formulated a comprehensive and exhaustive search strategy in an attempt to identify all relevant studies regardless of language or publication status (published, unpublished, in press, and in progress). In August 2009, we searched the following electronic journal and trial databases: MEDLINE, EMBASE, and CENTRAL. We also searched the electronic conference database of NLM Gateway, individual conference proceedings and prospective trials registers. We contacted researchers and relevant organizations and checked reference lists of all included studies.

SELECTION CRITERIA

Randomized controlled trials that compared the effect of ART consisting of three drugs initiated early in the disease at high CD4 counts as defined by the trial. Early initiation could be at levels of 201-350, 351-500, or >500 cells/microL, with the comparison group initiating ART at CD4 counts below 200 x 10(6) cells/microL or as defined by the trial.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed study eligibility, extracted data, and graded methodological quality. Data extraction and methodological quality were checked by a third author who resolved differences when these arose. Where clinically meaningful to do so, we meta-analysed dichotomous outcomes using the relative risk (RR) and report the 95% confidence intervals (95% CIs).

MAIN RESULTS

One completed trial (N = 816) and one sub-group (N = 249) of a larger trial met inclusion criteria. We combined the mortality data for both trials comparing initiating ART at CD4 levels at 350 cells/microL or between 200 and 350 cells/microL with deferring initiation of ART to CD4 levels of 250 cells/microL or 200 cells/microL. There was a statistically significant reduction in death when starting ART at higher CD4 counts. Risk of death was reduced by 74% (RR = 0.26; 95% CI: 0.11, 0.62; P = 0.002). Risk of tuberculosis was reduced by 50% in the groups starting ART early; this was not statistically significant, with the reduction as much as 74% or an increased risk of up to 12% (RR = 0.54; 95% CI: 0.26, 1.12; P = 0.01). Starting ART at enrollment (when participants had CD4 counts of 350 cells/microL) rather than deferring to starting at a CD4 count of 250 cells/microL reduced the risk of disease progression by 70%; this was not statistically significant, with the reduction in risk as much as 97% or an increased risk of up to 185% (RR = 0.30; 95% CI: 0.03, 2.85; P = 0.29).One RCT found no statistically significant difference in the number of independent Grade 3 or 4 adverse events occurring in the early and standard ART groups when we conducted an intention-to-treat analysis (RR = 1.72; 95% CI: 0.98, 3.03; P = 0.06). However, when analyzing only participants who actually commenced ART in the deferred group (n = 160), the trial authors report a statistically significant increase in the incidence of zidovudine-related anaemia (8.1%) compared with those in the early initiation group (3.4%) (RR = 0.42; 95% CI: 0.20, 0.88; P = 0.02).

AUTHORS' CONCLUSIONS

There is evidence of moderate quality that initiating ART at CD4 levels higher than 200 or 250 cells/microL reduces mortality rates in asymptomatic, ART-naive, HIV-infected people. Practitioners and policy-makers may consider initiating ART at levels </= 350 cells/microL for patients who present to health services and are diagnosed with HIV early in the infection.

Further benefits by early start of HIV treatment in low income countries: survival estimates of early versus deferred antiretroviral therapy

BACKGROUND

International HIV guidelines have recently shifted from a medium-late to an early-start treatment strategy. As a consequence, more people will be eligible to Highly Active Antiretroviral Therapy (HAART). We estimate mean life years gained using different treatment indications in low income countries.

METHODS

We carried out a systematic search to identify relevant studies on the treatment effect of HAART. Outcome from identified observational studies were combined in a pooled-analyses and we apply these data in a Markov life cycle model based on a hypothetical Tanzanian HIV population. Survival for three different HIV populations with and without any treatment is estimated. The number of patients included in our pooled-analysis is 35,047.

RESULTS

Providing HAART early when CD4 is 200-350 cells/microl is likely to be the best outcome strategy with an expected net benefit of 14.5 life years per patient. The model predicts diminishing treatment benefits for patients starting treatment when CD4 counts are lower. Patients starting treatment at CD4 50-199 and <50 cells/microl have expected net health benefits of 7.6 and 7.3 life years. Without treatment, HIV patients with CD4 counts 200-350; 50-199 and < 50 cells/microl can expect to live 4.8; 2.0 and 0.7 life years respectively.

CONCLUSIONS

This study demonstrates that HIV patients live longer with early start strategies in low income countries. Since low income countries have many constraints to full coverage of HAART, this study provides input to a more transparent debate regarding where to draw explicit eligibility criteria during further scale up of HAART.

Strategies to reduce early morbidity and mortality in adults receiving antiretroviral therapy in resource-limited settings

PURPOSE OF REVIEW

We review recently published literature concerning early morbidity and mortality during antiretroviral therapy (ART) among patients in resource-limited settings. We focus on articles providing insights into this burden of disease and strategies to address it.

RECENT FINDINGS

In sub-Saharan Africa, mortality rates during the first year of ART are very high (8-26%), with most deaths occurring in the first few months. This figure compares with 3-13% in programmes in Latin America and the Caribbean and 11-13% in south-east Asia. Risk factors generally reflect late presentation with advanced symptomatic disease. Key causes of morbidity and mortality include tuberculosis (TB), acute sepsis, cryptococcal meningitis, malignancy and wasting syndrome/chronic diarrhoea. Current literature shows that the fundamental need is for much earlier HIV diagnosis and initiation of ART. In addition, further studies provide data on the role of screening and prophylaxis against opportunistic diseases (particularly TB, bacterial sepsis and cryptococcal disease) and the management of specific opportunistic diseases and complications of ART. Effective and sustainable delivery of these interventions requires strengthening of programmes.

SUMMARY

Strategies to address this disease burden should include earlier HIV diagnosis and ART initiation, screening and prophylaxis for opportunistic infections, optimized management of specific diseases and treatment complications, and programme strengthening.

Early antiretroviral therapy mortality in resource-limited settings: what can we do about it?

PURPOSE OF REVIEW

Highly active antiretroviral therapy has markedly reduced HIV morbidity and mortality in industrialized countries. Expanded access to the 6.5 million individuals in immediate need of antiretroviral therapy using a public-health-systems approach is now promulgated as an international policy. An approximate 1.6 million individuals have already accessed antiretroviral therapy within programs in resource-poor settings.

RECENT FINDINGS

Early studies from these treatment programs confirm similar virologic and immunologic responses to antiretroviral therapy as were observed earlier in industrialized settings. While medium-term reductions in morbidity and mortality also parallel those reported from Europe and North America, of particular concern is the observation that mortality immediately after starting antiretroviral therapy in resource-poor settings is several-fold higher than that of similar patients initiating antiretroviral therapy in industrialized settings.

SUMMARY

This early mortality is multifactorial and is both a reflection of a very high preantiretroviral therapy mortality and a variety of factors such as comorbid conditions, late presentation, immune restoration disease, together with limited treatment and diagnostic options. Causes of mortality immediately prior to and during early antiretroviral therapy are reviewed and strategies to reduce mortality are identified and discussed.

Clinical prognostic value of RNA viral load and CD4 cell counts during untreated HIV-1 infection--a quantitative review

Background

The prognostic value of CD4 counts and RNA viral load for identifying treatment need in HIV-infected individuals depends on (a) variation within and among individuals, and (b) relative risks of clinical progression per unit CD4 or RNA difference.

Methodology/Principal Findings

We reviewed these measurements across (a) 30 studies, and (b) 16 cohorts of untreated seropositive adults. Median within-population interquartile ranges were 74,000 copies/mL for RNA with no significant change during the course of infection; and 330 cells/µL for CD4, with a slight proportional increase over infection. Applying measurement and physiological fluctuations observed on chronically infected patients, we estimate that 45% of population-level variation in RNA, and 25% of variation in CD4, were due to within-patient fluctuations. Comparing a patient with RNA at upper 75^th centile with a patient at median RNA, 5-year relative risks were 1.4 (95% CI 1.2–1.7) for AIDS and 1.5 (1.3–1.9) for death, without change over the course of infection. In contrast, for a patient with CD4 count at the lower 75^th centile, relative risks increased from 1.0 at seroconversion to maxima of 6.3 (4.4–8.9) for AIDS and 5.5 (2.7–10.1) for death by year 6, when the population median had fallen to 300 cells/µL. Below 300 cells/µL, prognostic power did not increase, due to a narrower CD4 range.

Conclusions

Findings support the current WHO recommendation (used with clinical criteria) to start antiretroviral treatment in low-income settings at CD4 thresholds of 200–350 cells/µL, without pre-treatment RNA monitoring – while not precluding earlier treatment based on clinical, socio-demographic or public health criteria.

HIV type 1 drug resistance in adults receiving highly active antiretroviral therapy in Abidjan, Côte d'Ivoire

As antiretroviral therapy continues to scale-up in developing countries, there is concern that high levels of HIV drug resistance to antiretroviral drugs will occur. Here we describe rates of emergence of HIV-1 drug resistance and factors associated with their occurrence among adults who received antiretroviral therapy (ART) for >1 year through the Côte d'Ivoire national drug access program from 1998 to 2003. To detect genotypic drug resistance, we sequenced all 1- and 2-year specimens with detectable HIV RNA viral load. To assess factors associated with emerging drug resistance, we used log normal regression with interval censoring, including covariates in the model for self-reported drug adherence, CD4 cell count, and HIV viral load at therapy initiation, and observed changes in these measures, type of prescribed ART drugs, diagnoses of opportunistic illness, and demographic characteristics. An estimated 14.2% [95% confidence limits (CL) 11.7, 16.9] and 26.6% (95% CL 22.7, 30.8) of patients developed primary drug-resistant mutations within 1 year and 2 years after initiation of therapy, respectively. Factors associated with drug resistance included drug nonadherence, partial or lack of viral suppression, higher viral load or lower CD4 at initiation of therapy, and initiation of ART with what is now considered substandard dual combination therapy. Our results demonstrate the need to strengthen adherence and continuity in treatment programs in order to avoid interruption of ART drugs. Treatment programs should pay attention to indicators of emerging drug resistance: incomplete or lesser decreases in viral load or increases in CD4 cell counts following initiation of therapy, and the occurrence of AIDS opportunistic illnesses.

Youth, unemployment, and male gender predict mortality in AIDS patients started on HAART in Nigeria

This retrospective study identifies risk factors for mortality in a cohort of HIV-positive adult patients treated with highly active antiretroviral therapy (HAART) in Jos, Nigeria. We analyzed clinical data from a cohort of 1552 patients enrolled in a HIV/acquired immune deficiency syndrome treatment program and started on HAART between December 2004 and 30 April 2006. Death was our study endpoint. Patients were followed in the study until death, being lost to follow-up, or the end of data collection, 1 December 2006. Baseline patient characteristics were compared using Wilcoxon Rank Sum Test for continuous variables and Pearson Chi-Square test for categorical variables to determine if certain demographic factors were associated with more rapid progression to death. The Cox proportional hazard multivariate model analysis was used to find risk factors. As of 1 December 2006, a total of 104 cases progressed to death. In addition to the expected association of CD4 count less than 50 at initiation of therapy and active tuberculosis with mortality, the patient characteristics independently associated with a more rapid progression to death after initiation of HAART were male gender, age less than 30 years old, and unemployment or unknown occupation status. Future research is needed to identify the confounding variables that may be amenable to targeted interventions aimed at ameliorating these health disparities.

Cost effectiveness of facility-based care, home-based care and mobile clinics for provision of antiretroviral therapy in Uganda

Stakeholders in HIV/AIDS care currently use different programmes for provision of antiretroviral therapy (ART) in Uganda. It is not known which of these represents the best value for money. To compare the cost effectiveness of home-based care (HBC), facility-based care (FBC) and mobile clinic care (MCC) for provision of ART in Uganda. Incremental cost-effectiveness analysis was performed using decision and Markov modeling of adult AIDS patients in WHO Clinical Stage 3 and 4 from the perspective of the Ugandan healthcare system. The main outcome measures were cost (year 2008 values), life expectancy in life-years (LY) and the incremental cost-effectiveness ratio (ICER) measured as cost per QALY or LY gained over 10 years. Ten-year mean undiscounted life expectancy was lowest for FBC (3.6 LY), followed by MCC (4.3 LY) and highest for HBC (5.3 LY), while the mean discounted QALYs were also lowest for FBC (2.3), followed by MCC (2.9) and highest for HBC (3.7). The 10-year mean costs per patient were lowest for FBC ($US3212), followed by MCC ($US4782) and highest for HBC ($US7033). The ICER was lower for MCC versus FBC ($US2241 per LY and $US2615 per QALY) than for HBC versus MCC ($US2251 per LY and $US2814 per QALY). FBC remained cost effective in univariate and probabilistic sensitivity analyses. FBC appears to be the most cost-effective programme for provision of ART in Uganda. This analysis supports the implementation of FBC for scale-up and sustainability of ART in Uganda. HBC and MCC would be competitive only if there is increased access, increased adherence or reduced cost.

Good adherence to HAART and improved survival in a community HIV/AIDS treatment and care programme: the experience of The AIDS Support Organization (TASO), Kampala, Uganda

Background

Poor adherence to highly active antiretroviral therapy (HAART) may result in treatment failure and death. Most reports of the effect of adherence to HAART on mortality come from studies where special efforts are made to provide HAART under ideal conditions. However, there are few reports of the impact of non-adherence to HAART on mortality from community HIV/AIDS treatment and care programmes in developing countries. We therefore conducted a study to assess the effect of adherence to HAART on survival in The AIDS Support Organization (TASO) community HAART programme in Kampala, Uganda.

Methods

The study was a retrospective cohort of 897 patients who initiated HAART at TASO clinic, Kampala, between May 2004 and December 2006. A total of 7,856 adherence assessments were performed on the data. Adherence was assessed using a combination of self-report and pill count methods. Patients who took ≤ 95% of their regimens were classified as non-adherent. The data was stratified at a CD4 count of 50 cells/mm³. Kaplan Meier curves and Cox proportional hazards regression models were used in the analysis.

Results

A total of 701 (78.2%) patients had a mean adherence to ART of > 95%. The crude death rate was 12.2 deaths per 100 patient-years, with a rate of 42.5 deaths per 100 patient-years for non-adherent patients and 6.1 deaths per 100 patient-years for adherent patients. Non-adherence to ART was significantly associated with mortality. Patients with a CD4 count of less than 50 cells/mm³ had a higher mortality (HR = 4.3; 95% CI: 2.22–5.56) compared to patients with a CD4 count equal to or greater than 50 cells/mm³ (HR = 2.4; 95% CI: 1.79–2.38).

Conclusion

Our study showed that good adherence and improved survival are feasible in community HIV/AIDS programmes such as that of TASO, Uganda. However, there is need to support community HAART programmes to overcome the challenges of funding to provide sustainable supplies particularly of antiretroviral drugs; provision of high quality clinical and laboratory support; and achieving a balance between expansion and quality of services. Measures for the early identification and treatment of HIV infected people including home-based VCT and HAART should be strengthened.

Cost-effectiveness of HIV monitoring strategies in resource-limited settings: a southern African analysis

BACKGROUND

Although the number of infected persons receiving highly active antiretroviral therapy (HAART) in low- and middle-income countries has increased dramatically, optimal disease management is not well defined.

METHODS

We developed a model to compare the costs and benefits of 3 types of human immunodeficiency virus monitoring strategies: symptom-based strategies, CD4-based strategies, and CD4 counts plus viral load strategies for starting, switching, and stopping HAART. We used clinical and cost data from southern Africa and performed a cost-effectiveness analysis. All assumptions were tested in sensitivity analyses.

RESULTS

Compared with the symptom-based approaches, monitoring CD4 counts every 6 months and starting treatment at a threshold of 200/muL was associated with a gain in life expectancy of 6.5 months (61.9 months vs 68.4 months) and a discounted lifetime cost savings of US $464 per person (US $4069 vs US $3605, discounted 2007 dollars). The CD4-based strategies in which treatment was started at the higher threshold of 350/microL provided an additional gain in life expectancy of 5.3 months at a cost-effectiveness of US $107 per life-year gained compared with a threshold of 200/microL. Monitoring viral load with CD4 was more expensive than monitoring CD4 counts alone, added 2.0 months of life, and had an incremental cost-effectiveness ratio of US $5414 per life-year gained relative to monitoring of CD4 counts. In sensitivity analyses, the cost savings from CD4 count monitoring compared with the symptom-based approaches was sensitive to cost of inpatient care, and the cost-effectiveness of viral load monitoring was influenced by the per test costs and rates of virologic failure.

CONCLUSIONS

Use of CD4 monitoring and early initiation of HAART in southern Africa provides large health benefits relative to symptom-based approaches for HAART management. In southern African countries with relatively high costs of hospitalization, CD4 monitoring would likely reduce total health care expenditures. The cost-effectiveness of viral load monitoring depends on test prices and rates of virologic failure.

Early mortality among adults accessing antiretroviral treatment programmes in sub-Saharan Africa

Two-thirds of the world's HIV-infected people live in sub-Saharan Africa, and more than 1.5 million of them die annually. As access to antiretroviral treatment has expanded within the region; early pessimism concerning the delivery of antiretroviral treatment using a large-scale public health approach has, at least in the short term, proved to be broadly unfounded. Immunological and virological responses to ART are similar to responses in patients treated in high-income countries. Despite this, however, early mortality rates in sub-Saharan Africa are very high; between 8 and 26% of patients die in the first year of antiretroviral treatment, with most deaths occurring in the first few months. Patients typically access antiretroviral treatment with advanced symptomatic disease, and mortality is strongly associated with baseline CD4 cell count less than 50 cells/mul and WHO stage 4 disease (AIDS). Although data are limited, leading causes of death appear to be tuberculosis, acute sepsis, cryptococcal meningitis, malignancy and wasting syndrome. Mortality rates are likely to depend not only on the care delivered by antiretroviral treatment programmes, but more fundamentally on how advanced disease is at programme enrollment and the quality of preceding healthcare. In addition to improving delivery of antiretroviral treatment and providing it free of charge to the patient, strategies to reduce mortality must include earlier diagnosis of HIV infection, strengthening of longitudinal HIV care and timely initiation of antiretroviral treatment. Health systems delays in antiretroviral treatment initiation must be minimized, especially in patients who present with advanced immunodeficiency.

Duration from seroconversion to eligibility for antiretroviral therapy and from ART eligibility to death in adult HIV-infected patients from low and middle-income countries: collaborative analysis of prospective studies

BACKGROUND

Estimation of the number of people in need of antiretroviral therapy (ART) in resource-limited settings requires information on the time from seroconversion to ART eligibility and from ART eligibility to death.

OBJECTIVES

To estimate duration from seroconversion to different ART eligibility criteria and from ART eligibility to death in HIV-infected adults in low-income and middle-income countries.

METHODS

Participants with documented seroconversion from five cohorts (two cohorts from Uganda, two from Thailand and one from Côte d'Ivoire) were analysed. We used Weibull survival models and Bayesian simulation methods to model true (unobserved) first time of treatment eligibility. We set a consistency constraint so that the mean duration from seroconversion to death was equal to the mean from seroconversion to ART eligibility plus the mean from eligibility to death.

RESULTS

We analysed data from 2072 participants, 16 157 person-years of follow-up and 794 deaths. For the criterion CD4 T-lymphocyte count <200 cells x10(6)/l, the median duration from seroconversion to ART eligibility was 6.1 years (95% credibility interval 3.3-10.4) for all studies and 7.6 years (95% credibility interval 3.4-15.2) for all but the Thai cohorts. Corresponding estimates for the time from CD4 T-lymphocyte count <200 cells x10(6)/l to death were 2.1 years (0.7-4.8) and 2.7 years (0.8-8.4). When including all cohorts, the mean time from serconversion to CD4 T-lymphocyte count <200 cells x10(6)/l and from CD4 T-lymphocyte count <200 cells x10(6)/l to death represented 66% (38-87%) and 34% (13-62%), respectively of the total survival time.

CONCLUSIONS

The duration of different ART eligibility criteria to death was longer than the estimates used in previous calculations of the number of people needing ART. However, uncertainty in estimates was considerable and heterogeneity across cohorts important.

Scaling up antiretroviral therapy in South Africa: the impact of speed on survival

BACKGROUND

Only 33% of eligible human immunodeficiency virus (HIV)-infected patients in South Africa receive antiretroviral therapy (ART). We sought to estimate the impact of alternative ART scale-up scenarios on patient outcomes from 2007-2012.

METHODS

Using a simulation model of HIV infection with South African data, we projected HIV-associated mortality with and without effective ART for an adult cohort in need of therapy (2007) and for adults who became eligible for treatment (2008-2012). We compared 5 scale-up scenarios: (1) zero growth, with a total of 100,000 new treatment slots; (2) constant growth, with 600,000; (3) moderate growth, with 2.1 million; (4) rapid growth, with 2.4 million); and (5) full capacity, with 3.2 million.

RESULTS

Our projections showed that by 2011, the rapid growth scenario fully met the South African need for ART; by 2012, the moderate scenario met 97% of the need, but the zero and constant growth scenarios met only 28% and 52% of the need, respectively. The latter scenarios resulted in 364,000 and 831,000 people alive and on ART in 2012. From 2007 to 2012, cumulative deaths in South Africa ranged from 2.5 million under the zero growth scenario to 1.2 million under the rapid growth scenario.

CONCLUSIONS

Alternative ART scale-up scenarios in South Africa will lead to differences in the death rate that amount to more than 1.2 million deaths by 2012. More rapid scale-up remains critically important.

Assessing efficiency and costs of scaling up HIV treatment

INTRODUCTION

Whereas cost-effectiveness/utility analyses theoretically assess efficiency in HIV treatment, in practice they are of limited use to policy makers who are also concerned with the total costs of scaling up. This paper proposes an approach to simultaneously assessing both factors when setting priorities for HIV treatment.

METHODS

Three interventions were assessed: a no antiretroviral therapy (ART) status quo, ART including first-line only, and ART including first and second-line regimens. Data were from a cohort receiving healthcare in a poor South African setting. Markov modelling was used to calculate patient-level lifetime costs and quality-adjusted life-years (QALY) as well as population-level total costs and QALY in each intervention. Linear programming was used to assess efficiency at the population level.

RESULTS

First-line ART costs US$795 per QALY gained compared to no ART, while first and second-line costs US$1625 compared to first-line alone. The efficiency of either ART strategy depends on the HIV treatment budget. If this is less than US$10 billion during the planning period, first-line ART is most efficient. A combination of first-line with first and second-line treatment is most efficient if the budget is US$10-12 billion. Using both first and second-line treatment for everyone becomes efficient as the main strategy only at budgets greater than US$13 billion.

CONCLUSION

An approach has been developed to HIV treatment priority setting that simultaneously considers efficiency and the costs of scaling up. This can help to establish explicit and evidence-based priorities and budgets to meet scaling up challenges.

Outcomes from monitoring of patients on antiretroviral therapy in resource-limited settings with viral load, CD4 cell count, or clinical observation alone: a computer simulation model

BACKGROUND

In lower-income countries, WHO recommends a population-based approach to antiretroviral treatment with standardised regimens and clinical decision making based on clinical status and, where available CD4 cell count, rather than viral load. Our aim was to study the potential consequences of such monitoring strategies, especially in terms of survival and resistance development.

METHODS

A validated computer simulation model of HIV infection and the effect of antiretroviral therapy was used to compare survival, use of second-line regimens, and development of resistance that result from different strategies-based on viral load, CD4 cell count, or clinical observation alone-for determining when to switch people starting antiretroviral treatment with the WHO-recommended first-line regimen of stavudine, lamivudine, and nevirapine to second-line antiretroviral treatment.

FINDINGS

Over 5 years, the predicted proportion of potential life-years survived was 83% with viral load monitoring (switch when viral load >500 copies per mL), 82% with CD4 cell count monitoring (switch at 50% drop from peak), and 82% with clinical monitoring (switch when two new WHO stage 3 events or a WHO stage 4 event occur). Corresponding values over 20 years were 67%, 64%, and 64%. Findings were robust to variations in model specification in extensive univariable and multivariable sensitivity analyses. Although survival was slightly longer with viral load monitoring, this strategy was not the most cost effective.

INTERPRETATION

For patients on the first-line regimen of stavudine, lamivudine, and nevirapine the benefits of viral load or CD4 cell count monitoring over clinical monitoring alone are modest. Development of cheap and robust versions of these assays is important, but widening access to antiretrovirals-with or without laboratory monitoring-is currently the highest priority.

Mortality in HIV-infected Ugandan adults receiving antiretroviral treatment and survival of their HIV-uninfected children: a prospective cohort study

BACKGROUND

Antiretroviral therapy (ART) is increasingly available in Africa, but physicians and clinical services are few. We therefore assessed the effect of a home-based ART programme in Uganda on mortality, hospital admissions, and orphanhood in people with HIV-1 and their household members.

METHODS

In 2001, we enrolled and followed up 466 HIV-infected adults and 1481 HIV-uninfected household members in a prospective cohort study. After 5 months, we provided daily co-trimoxazole (160 mg trimethoprim and 800 mg sulfamethoxazole) prophylaxis to HIV-infected participants. Between May, 2003, and December, 2005, we followed up 138 infected adults who were eligible and 907 new HIV-infected participants and their HIV-negative household members in a study of ART (mainly stavudine, lamivudine, and nevirapine). Households were visited every week by lay providers, and no clinic visits were scheduled after enrolment. We compared rates of death, hospitalisation, and orphanhood during different study periods and calculated the number needed to treat to prevent an outcome.

FINDINGS

233 (17%) of 1373 participants with HIV and 40 (1%) of 4601 HIV-uninfected household members died. During the first 16 weeks of ART and co-trimoxazole, mortality in HIV-infected participants was 55% lower than that during co-trimoxazole alone (14 vs 16 deaths per 100 person-years; adjusted hazard ratio 0.45, 95% CI 0.27-0.74, p=0.0018), and after 16 weeks, was reduced by 92% (3 vs 16 deaths per 100 person-years; 0.08, 0.06-0.13, p<0.0001). Compared with no intervention, ART and co-trimoxazole were associated with a 95% reduction in mortality in HIV-infected participants (5 vs 27 deaths per 100 person-years; 0.05, 0.03-0.08, p<0.0001), 81% reduction in mortality in their uninfected children younger than 10 years (0.2 vs 1.2 deaths per 100 person-years; 0.19, 0.06-0.59, p=0.004), and a 93% estimated reduction in orphanhood (0.9 vs 12.8 per 100 person-years of adults treated; 0.07, 0.04-0.13, p<0.0001).

INTERPRETATION

Expansion of access to ART and co-trimoxazole prophylaxis could substantially reduce mortality and orphanhood among adults with HIV and their families living in resource-poor settings.

Change over time of mortality predictors after HAART initiation in a Senegalese cohort

BACKGROUND

In 1998, Senegal was among the first sub-Saharan African countries to launch a Highly active anti-retroviral therapy (HAART) access program. Initial studies have demonstrated the feasibility and efficacy of this initiative. Analyses showed a peak of mortality short after starting HAART warranting an investigation of early and late mortality predictors.

METHODS

404 HIV-1-infected Senegalese adult patients were enrolled and data censored as of September 2005. Predictor effects on mortality were first examined over the whole follow-up period (median 46 months) using a Cox model and Shoenfeld residuals. Then, changes of these effects were examined separately over the early and late treatment periods; i.e., less and more than 6-month follow-up.

RESULTS

During the early period, baseline body mass index and baseline total lymphocyte count were significant predictors of mortality (Hazard Ratios 0.82 [0.72-0.93] and 0.80 [0.69-0.92] per 200 cell/mm3, respectively) while baseline viral load was not significantly associated with mortality. During the late period, viro-immunological markers (baseline CD4-cell count and 6-month viral load) had the highest impact. In addition, the viral load at 6-month was a significant predictor (HR = 1.42 [1.20-1.66]).

CONCLUSION

In this cohort, impaired clinical status could explain the high early mortality rate while viro-immunological markers were rather predictors of late mortality.

Morbidity before and after HAART initiation in Sub-Saharan African HIV-infected adults: a recurrent event analysis

The incidence and determinants of severe morbidity recurrence in sub-Saharan African HIV-infected adults on antiretroviral therapy (ART) have never been reported. In a prospective cohort study of HIV-infected adults in Abidjan the association of severe morbidity occurrence and recurrence with follow-up CD4 counts and ART on/off status was analyzed by means of multivariate failure analysis for recurrent events (Prentice, Williams, and Peterson model). A total of 608 patients (median CD4 290/mm3 ) was followed off ART for 1824 person-years (PY). Of these 187 started HAART (median CD4 174/mm3 ) and were followed for 328 PY. The incidence of first, second, and third severe morbidity events was 40.6/100 PY, 68.4/100 PY, and 93.9/100 PY during the off-ART period, and 28.4/100 PY, 39.4/100 PY, and 37.6/100 PY during the on-ART period, respectively. The rates of recurrences were higher than the rates of first episodes for almost all diseases, even after stratifying by CD4 count and by ART on/off status. In multivariate analysis, the time-updated CD4 count was independently associated with increasing rates of morbidity first events and recurrences, after adjustment on other covariates (p > 10(4) ). By contrast, there was no association between the ART on/off status and the morbidity rates after adjustment for CD4 count (p = 0.37). Introducing ART led to a clear reduction in morbidity, mainly related to the ART-induced increase in CD4 count. In HIV-infected patients on ART, the incidence of severe morbidity varied with the past history of morbidity. The past history of morbidity should be taken into account when comparing HIV morbidity rates before and after ART initiation.

Estimates of opportunistic infection incidence or death within specific CD4 strata in HIV-infected patients in Abidjan, Côte d'Ivoire: impact of alternative methods of CD4 count modelling

CD4 lymphocyte count is an important surrogate marker of HIV disease progression, but it is often unavailable at the time of clinical events. We analysed data from the Cotrame cohort (1999-2004) and the Trivacan Structured Treatment Interruption trial (2002-2005) to estimate the incidence of opportunistic infections and death within specific CD4 strata in HIV-infected patients receiving highly active antiretroviral therapy (HAART) in sub-Saharan Africa. We used three methods of CD4 modelling: the first assumed that CD4 cell count remained constant until the next measurement; the second assumed that it changed immediately to the level of the subsequent measurement; and the third assumed that it followed a linear function between two consecutive CD4 measurements. The cohort used in this analysis consisted of 981 patients. The incidence rates of opportunistic infections were highest in the lower CD4 strata and decreased in the higher CD4 count strata. The incidence rates of mild opportunistic infections and severe bacterial infections, however, remained high in the highest CD4 stratum. Although all confidence intervals overlapped among the three methods, the incidence rate estimates showed differences of up to 74% in the lowest CD4 stratum. Different methods of estimating CD4 counts at the time of clinical events led to minor differences in incidence rates, except in the CD4 stratum <50 cells/mm(3), where the follow-up time was shorter. All of the models indicate that the overall incidence of opportunistic infections under HAART in sub-Saharan Africa is high. This suggests that prophylaxis against opportunistic infections may be needed even for patients receiving HAART.

Gender distribution of adult patients on highly active antiretroviral therapy (HAART) in Southern Africa: a systematic review

Background

HIV and AIDS are significant and growing public health concerns in southern Africa. The majority of countries in the region have national adult HIV prevalence estimates exceeding 10 percent. The increasing availability of highly active antiretroviral therapy (HAART) has potential to mitigate the situation. There is however concern that women may experience more barriers in accessing treatment programs than men.

Methods

A systematic review of the literature was carried out to describe the gender distribution of patients accessing highly active antiretroviral therapy (HAART) in Southern Africa. Data on number of patients on treatment, their mean or median age and gender were obtained and compared across studies and reports.

Results

The median or mean age of patients in the studies ranged from 33 to 39 years. While female to male HIV infection prevalence ratios in the southern African countries ranged from 1.2:1 to 1.6:1, female to male ratios on HAART ranged from 0.8: 1 to 2.3: 1. The majority of the reports had female: male ratio in treatment exceeding 1.6. Overall, there were more females on HAART than there were males and this was not solely explained by the higher HIV prevalence among females compared to males.

Conclusion

In most Southern African countries, proportionally more females are on HIV antiretroviral treatment than men, even when the higher HIV infection prevalence in females is accounted for. There is need to identify the factors that are facilitating women's accessibility to HIV treatment. As more patients access HAART in the region, it will be important to continue assessing the gender distribution of patients on HAART.

The cost-effectiveness of antiretroviral treatment in Khayelitsha, South Africa--a primary data analysis

Background

Given the size of the HIV epidemic in South Africa and other developing countries, scaling up antiretroviral treatment (ART) represents one of the key public health challenges of the next decade. Appropriate priority setting and budgeting can be assisted by economic data on the costs and cost-effectiveness of ART. The objectives of this research were therefore to estimate HIV healthcare utilisation, the unit costs of HIV services and the cost per life year (LY) and quality adjusted life year (QALY) gained of HIV treatment interventions from a provider's perspective.

Methods

Data on service utilisation, outcomes and costs were collected in the Western Cape Province of South Africa. Utilisation of a full range of HIV healthcare services was estimated from 1,729 patients in the Khayelitsha cohort (1,146 No-ART patient-years, 2,229 ART patient-years) using a before and after study design. Full economic costs of HIV-related services were calculated and were complemented by appropriate secondary data. ART effects (deaths, therapy discontinuation and switching to second-line) were from the same 1,729 patients followed for a maximum of 4 years on ART. No-ART outcomes were estimated from a local natural history cohort. Health-related quality of life was assessed on a sub-sample of 95 patients. Markov modelling was used to calculate lifetime costs, LYs and QALYs and uncertainty was assessed through probabilistic sensitivity analysis on all utilisation and outcome variables. An alternative scenario was constructed to enhance generalizability.

Results

Discounted lifetime costs for No-ART and ART were US$2,743 and US$9,435 over 2 and 8 QALYs respectively. The incremental cost-effectiveness ratio through the use of ART versus No-ART was US$1,102 (95% CI 1,043-1,210) per QALY and US$984 (95% CI 913-1,078) per life year gained. In an alternative scenario where adjustments were made across cost, outcome and utilisation parameters, costs and outcomes were lower, but the ICER was similar.

Conclusion

Decisions to scale-up ART across sub-Saharan Africa have been made in the absence of incremental lifetime cost and cost-effectiveness data which seriously limits attempts to secure funds at the global level for HIV treatment or to set priorities at the country level. This article presents baseline cost-effectiveness data from one of the longest running public healthcare antiretroviral treatment programmes in Africa that could assist in enhancing efficient resource allocation and equitable access to HIV treatment.

Short-term risk of AIDS or death in people infected with HIV-1 before antiretroviral therapy in South Africa: a longitudinal study

BACKGROUND

In sub-Saharan Africa, data for short-term risk of AIDS or death, which might inform decisions about when to start antiretroviral therapy (ART), are scarce. Our aim was to investigate these risks in patients who had no access to ART or who were given zidovudine alone.

METHODS

6-month risks (%) of death, AIDS, and combined risk of AIDS and death (AIDS/death) were calculated according to CD4-cell count category of less than 200 cells per microL, 200-350 cells per microL, or greater than 350 cells per microL, stratified by WHO clinical stages 1 and 2 combined, 3, or 4 in untreated patients (n=1399) seeking care in tertiary public-sector HIV clinics before widespread availability of ART in Cape Town, South Africa.

FINDINGS

Risk of death for WHO stages 1 and 2 was 3.5% for those with less than 200 cells per microL, 2.8% for 200-350 cells per microL, and 1.2% for greater than 350 cells per microL. The corresponding rates for WHO stage 3 were 10.8%, 4.3%, and 4.9% and for stage 4, 22.2%, 10.3%, and 13.8%. 52% (90) of deaths took place in patients without AIDS. 6-month risk of AIDS for WHO stages 1 and 2 was 3.5% for those with less than 200 cells per microL, 1.6% for 200-350 cells per microL, and zero for greater than 350 cells per microL. The corresponding rates for those with WHO stage 3 disease were 17.4%, 7.0%, and 2.2%.

INTERPRETATION

In this study, risk of AIDS in patients with a CD4-cell count of less than 200 cells per microL or greater than 350 cells per microL was similar to that previously reported from European cohorts, but was 1.9 times greater for those with CD4-cell counts of between 200 and 350 cells per microL. The high death rate before development of AIDS and a high risk of AIDS in those with CD4-cell counts of 200-350 cells per microL indicate that delay in initiation of ART is associated with increased morbidity and mortality. These findings might help to amend criteria for start of ART in resource-limited settings.

HIV/AIDS epidemiology, pathogenesis, prevention, and treatment

The HIV-1 pandemic is a complex mix of diverse epidemics within and between countries and regions of the world, and is undoubtedly the defining public-health crisis of our time. Research has deepened our understanding of how the virus replicates, manipulates, and hides in an infected person. Although our understanding of pathogenesis and transmission dynamics has become more nuanced and prevention options have expanded, a cure or protective vaccine remains elusive. Antiretroviral treatment has transformed AIDS from an inevitably fatal condition to a chronic, manageable disease in some settings. This transformation has yet to be realised in those parts of the world that continue to bear a disproportionate burden of new HIV-1 infections and are most affected by increasing morbidity and mortality. This Seminar provides an update on epidemiology, pathogenesis, treatment, and prevention interventions pertinent to HIV-1.

The potential impact of enhanced diagnostic techniques for tuberculosis driven by HIV: a mathematical model

OBJECTIVE

To explore the potential impact of enhanced tuberculosis (TB) diagnostic techniques as a TB control strategy in an adult population with high HIV prevalence.

DESIGN

A compartmental difference-equation model of TB/HIV was developed using parameter estimates from the literature.

METHODS

The impact of five TB control interventions (rapid molecular testing, mycobacterial culture, community-wide and HIV-targeted active case finding, and highly active antiretroviral therapy) on TB incidence, prevalence, and mortality was modeled in a steady-state population with an HIV prevalence of 17% and annual TB incidence of 409 per 100 000. Sensitivity analyses assessed the influence of each model parameter on the interventions' mortality impact.

RESULTS

Enhanced diagnostic techniques (rapid molecular testing or culture) are each projected to reduce TB prevalence and mortality by 20% or more, an impact similar to that of active case-finding in 33% of the general community and greater than the effect achievable by case-finding or antiretroviral treatment efforts in HIV-positive patients alone. The projected impact of enhanced diagnostics on TB incidence (< 10% reduction) is smaller. The impact of TB diagnostics is sensitive to the quality of existing diagnostic standards and the level of access to diagnostic services, but is robust across a wide range of population parameters including HIV and TB incidence.

CONCLUSIONS

Enhanced TB diagnostic techniques may have substantial impact on TB morbidity and mortality in HIV-endemic regions. As TB rates continue to increase in these areas, enhanced diagnostic techniques merit further consideration as TB control strategies.

Tuberculosis in sub-Saharan Africa: opportunities, challenges, and change in the era of antiretroviral treatment

Rapid scale-up of antiretroviral treatment programmes is happening in Africa, driven by international advocacy and policy directives and supported by unprecedented donor funding and technical assistance. This welcome development offers hope to millions of HIV-infected Africans, among whom tuberculosis is the major cause of serious illness and death. Little in the way of HIV diagnosis or care was previously offered to patients with tuberculosis, by either national tuberculosis or AIDS control programmes, with tuberculosis services focused exclusively on diagnosis and treatment of rising numbers of patients. Tuberculosis control in Africa has yet to adapt to the new climate of antiretroviral availability. Many barriers exist, from drug interactions to historic differences in the way that tuberculosis and HIV are perceived, but failure to successfully integrate HIV and tuberculosis control will threaten the viability of both programmes. Here, we review tuberculosis epidemiology in Africa and policy implications of HIV/AIDS treatment scale-up.

Mortality of HIV-1-infected patients in the first year of antiretroviral therapy: comparison between low-income and high-income countries

BACKGROUND

Highly active antiretroviral therapy (HAART) is being scaled up in developing countries. We compared baseline characteristics and outcomes during the first year of HAART between HIV-1-infected patients in low-income and high-income settings.

METHODS

18 HAART programmes in Africa, Asia, and South America (low-income settings) and 12 HIV cohort studies from Europe and North America (high-income settings) provided data for 4810 and 22,217, respectively, treatment-naïve adult patients starting HAART. All patients from high-income settings and 2725 (57%) patients from low-income settings were actively followed-up and included in survival analyses.

FINDINGS

Compared with high-income countries, patients starting HAART in low-income settings had lower CD4 cell counts (median 108 cells per muL vs 234 cells per muL), were more likely to be female (51%vs 25%), and more likely to start treatment with a non-nucleoside reverse transcriptase inhibitor (NNRTI) (70%vs 23%). At 6 months, the median number of CD4 cells gained (106 cells per muL vs 103 cells per muL) and the percentage of patients reaching HIV-1 RNA levels lower than 500 copies/mL (76%vs 77%) were similar. Mortality was higher in low-income settings (124 deaths during 2236 person-years of follow-up) than in high-income settings (414 deaths during 20,532 person-years). The adjusted hazard ratio (HR) of mortality comparing low-income with high-income settings fell from 4.3 (95% CI 1.6-11.8) during the first month to 1.5 (0.7-3.0) during months 7-12. The provision of treatment free of charge in low-income settings was associated with lower mortality (adjusted HR 0.23; 95% CI 0.08-0.61).

INTERPRETATION

Patients starting HAART in resource-poor settings have increased mortality rates in the first months on therapy, compared with those in developed countries. Timely diagnosis and assessment of treatment eligibility, coupled with free provision of HAART, might reduce this excess mortality.

The economics of HIV/AIDS in low-income countries: the case for prevention

There are two approaches to reducing the burden of sickness and death associated with the human immunodeficiency virus (HIV), which leads to acquired immunodeficiency syndrome (AIDS): treatment and prevention. Despite large international aid flows for HIV/AIDS, the needs for prevention and treatment in low- and middle-income countries outstrip the resources available. Thus, it becomes necessary to set priorities. With limited resources, should the focus of efforts to combat HIV/AIDS be on prevention or treatment? I discuss the range of prevention and treatment alternatives and examine their cost effectiveness. I consider various arguments that have been raised against the use of cost-effectiveness analysis in setting public policy priorities for the response to HIV/AIDS in developing countries. I conclude that promoting AIDS treatment using antiretrovirals in resource-constrained countries comes at a huge cost in terms of avoidable deaths that could be prevented through interventions that would substantially lower the scale of the epidemic.

Cost-effectiveness of highly active antiretroviral therapy in South Africa

BACKGROUND

Little information exists on the impact of highly active antiretroviral therapy (HAART) on health-care provision in South Africa despite increasing scale-up of access to HAART and gradual reduction in HAART prices.

METHODS AND FINDINGS

Use and cost of services for 265 HIV-infected adults without AIDS (World Health Organization [WHO] stage 1, 2, or 3) and 27 with AIDS (WHO stage 4) receiving HAART between 1995 and 2000 in Cape Town were compared with HIV-infected controls matched for baseline WHO stage, CD4 count, age, and socioeconomic status, who did not receive antiretroviral therapy (ART; No-ART group). Costs of service provision (January 2004 prices, USD 1 = 7.6 Rand) included local unit costs, and two scenarios for HAART prices for WHO recommended first-line regimens: scenario 1 used current South African public-sector ART drug prices of $730 per patient-year (PPY), whereas scenario 2 was based on the anticipated public-sector price for locally manufactured drug of $181 PPY. All analyses are presented in terms of patients without AIDS and patients with AIDS. For patients without AIDS, the mean number of inpatient days PPY was 1.08 (95% confidence interval [CI]: 0.97-1.19) for the HAART group versus 3.73 (95% CI: 3.55-3.97) for the No-ART group, and 8.71 (95% CI: 8.40-9.03) versus 4.35 (95% CI: 4.12-5.61), respectively, for mean number of outpatient visits PPY. Average service provision PPY was $950 for the No-ART group versus $1,342 and $793 PPY for the HAART group for scenario 1 and 2, respectively, whereas the incremental cost per life-year gained (LYG) was $1,622 for scenario 1 and $675 for scenario 2. For patients with AIDS, mean inpatients days PPY was 2.04 (95% CI: 1.63-2.52) for the HAART versus 15.36 (95% CI: 13.97-16.85) for the No-ART group. Mean outpatient visits PPY was 7.62 (95% CI: 6.81-8.49) compared with 6.60 (95% CI: 5.69-7.62) respectively. Average service provision PPY was $3,520 for the No-ART group versus $1,513 and $964 for the HAART group for scenario 1 and 2, respectively, whereas the incremental cost per LYG was cost saving for both scenarios. In a sensitivity analysis based on the lower (25%) and upper (75%) interquartile range survival percentiles, the incremental cost per LYG ranged from $1,557 to $1,772 for the group without AIDS and from cost saving to $111 for patients with AIDS.

CONCLUSION

HAART is a cost-effective intervention in South Africa, and cost saving when HAART prices are further reduced. Our estimates, however, were based on direct costs, and as such the actual cost saving might have been underestimated if indirect costs were also included.

When to Initiate Highly Active Antiretroviral Therapy in Sub-Saharan Africa? A South African Cost-Effectiveness Study

Background

Large-scale programmes increasing access to highly active antiretroviral therapy (HAART) are being implemented in sub-Saharan Africa. However, cost-effectiveness of initiating treatment at different CD4 count thresholds has not been explored in resource-poor settings.

Methods

A cost-effectiveness analysis was conducted from a public health perspective using primary treatment outcomes, healthcare utilisation and cost data (Jan 2004 local prices; US$1=7.6 Rands) derived from the Cape Town AIDS Cohort. A Markov state-transition model was developed to estimate life-expectancy, lifetime costs, quality-adjusted life-years (QALYs), cost per life-year and QALY gained for initiating HAART at three CD4 cell count thresholds (<200/μl, 200–350/μl and >350/μl), including the no antiretroviral therapy (No-ART) alternative. Each treatment option was compared with the next most effective undominated option.

Results

Mean life-expectancy was 6.2, 18.8, 21.0 and 23.3 years; discounted (8%) QALYs were 3.1, 6.2, 6.7 and 7.4; and discounted lifetime costs were US$5,250, US$5,434, US$5,740, US$6,588 for No-ART, and therapy initiation at <200/μl, 200–350/μl and >350/μl scenarios respectively. Clinical benefits increased significantly with early therapy initiation. Initiating therapy at <200/μl had an incremental cost-effectiveness ratio (ICER) of US$54 per QALY versus No-ART, 200–350/μl had an ICER of US$616 versus therapy initiation at <200/μl, and >350/μl had an ICER of US$1,137 versus therapy initiation at 200–350/μl ICERs were sensitive to HAART cost.

Conclusions

HAART is reasonably cost-effective for HIV-infected patients in South Africa, and most effective if initiated when CD4 count >200/μl. Deferring treatment to <200/μl would reduce the aggregate cost of treatment, but this should be balanced against the significant clinical benefits associated with early therapy.