Elsevier

Drug and Alcohol Dependence

Volume 125, Issue 3, 1 October 2012, Pages 260-266
Drug and Alcohol Dependence

Cost-effectiveness of integrating methadone maintenance and antiretroviral treatment for HIV-positive drug users in Vietnam's injection-driven HIV epidemics

https://doi.org/10.1016/j.drugalcdep.2012.02.021Get rights and content

Abstract

Drug use negatively affects adherence to and outcomes of antiretroviral treatment (ART). This study evaluated the cost-effectiveness of integrating methadone maintenance treatment (MMT) with ART for HIV-positive drug users (DUs) in Vietnam.

A decision analytical model was developed to compare the costs and consequences of 3 HIV/AIDS treatment strategies for DUs: (1) only ART, (2) providing ART and MMT in separated sites (ART–MMT), and (3) integrating ART and MMT with direct administration (DAART-MMT). The model was parameterized using empirical data of costs and outcomes extracted from the MMT and ART cohort studies in Vietnam, and international published sources. Probabilistic sensitivity analysis was conducted to examine the model's robustness.

The base-case analysis showed that the cost-effectiveness ratio of ART, DAART-MMT, and ART–MMT strategies was USD 1358.9, 1118.0 and 1327.1 per 1 Quality-Adjusted Life Year (QALY), equivalent to 1.22, 1.00, and 1.19 times Gross Domestic Product per capita (GDPpc). The incremental cost-effectiveness ratio for DAART-MMT and ART–MMT versus ART strategy was 569.4 and 1227.8, approximately 0.51 and 1.10 times GDPpc/QALY. At the willingness to pay threshold of 3 times GDPpc, the probability of being cost-effective of DAART-MMT versus ART was 86.1%.

These findings indicated that providing MMT along with ART for HIV-positive DUs is a cost-effective intervention in Vietnam. Integrating MMT and ART services could facilitate the use of directly observed therapy that supports treatment adherence and brings about clinically important improvements in health outcomes. This approach is also incrementally cost-effective in this large injection-driven HIV epidemic.

Section snippets

Background

Asia and the Pacific has experienced the second highest burden of the HIV epidemic, which is largely driven by drug injection (World Health Organization, 2010). In this region, there are about 3.9 million drug users (DUs) accounting for more than a half of the total DUs in the world (Bergenstrom and Abdul-Quader, 2010). Among Asian countries, Vietnam has a typical course of the regional HIV epidemics, which emerged in drug injecting populations, and then concentrated in high-risk groups (The

Antiretroviral treatment services and scope of analysis

The Vietnam National HIV/AIDS care and treatment guideline, adopt from the WHO (2006), determined the eligibility criteria for antiretroviral therapy (ART) at WHO HIV stages 3 and 4, or a CD4 count less than 250 cells/μl (Ministry of Health, 2009b, World Health Organization, 2006). The management of HIV-positive DUs is not significantly different from that of other patient groups. HIV-positive DUs, eligible for ART, are provided first line regimens including Zidovudine/Stavudine + Lamivudine + 

Results

Table 2 presents the average costs and QALYs generated from the model in deterministic and probabilistic analysis. At base-case values of all parameters, the cost-effectiveness ratio of ART, DAART-MMT, and ART–MMT strategies was 1358.9, 1118.0 and 1327.1 (USD/QALY), equivalent to 1.22, 1.00, and 1.19 times GDPpc. Compared to the ART strategy, providing MMT for HIV-positive DUs in either standalone sites or integrated model, such as DAART-MMT, incurred higher costs but significantly better

Discussion

We developed a decision analytical model to evaluate the cost-effectiveness of HIV care and treatment strategies for DUs that involved both MMT and ART services. The results indicated that providing MMT along with ART for HIV-positive DUs is incrementally cost-effective from the perspective of health services providers. In addition, the hypothetical model, which integrates ART with MMT and adapts the DOT, brought about an extra 0.047 QALY – approximately 0.5 times standard deviation of health

Conclusions

In conclusion, providing MMT for HIV-positive DUs during ART is incrementally cost-effective. Moreover, direct observations of health workers for drug taking during patients’ visits are potentially useful HIV/AIDS care and treatment outcomes. The results of this study support the scale-up and integration of MMT services with ART for HIV-positive DUs in Vietnam. In addition, the high level of uncertainty observed in this analysis suggests that interventions on patients’ retention, adherence and

Role of funding source

No funding source declared.

Contributors

BXT, AO, ATD, LTN, PXV, PJ, and SH have been involved in designing the study and writing the manuscript. BXT analyzed the secondary data and developed the economic evaluation model. LTN and SM were the co-principle investigator who designed and implemented the original MMT cohort study. All authors have read and approved the final manuscript for submission.

Conflict of interest

All other authors declare that they have no conflicts of interest.

Acknowledgments

We wish to acknowledge the Vietnam Administration of HIV/AIDS Control (VAAC), Ministry of Health for their approval on secondary data use.

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    Supplementary material can be found by accessing the online version of this paper at http://dx.doi.org/.

    1

    These authors contributed equally to this work.

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