Cost-effectiveness of voluntary HIV screening in Russia.

Russia has one of the world's fastest growing HIV epidemics, and HIV screening has been widespread. Whether such screening is an effective use of resources is unclear. We used epidemiologic and economic data from Russia to develop a Markov model to estimate costs, quality of life and survival associated with a voluntary HIV screening programme compared with no screening in Russia. We measured discounted lifetime health-care costs and quality-adjusted life years (QALYs) gained. We varied our inputs in sensitivity analysis. Early identification of HIV through screening provided a substantial benefit to persons with HIV, increasing life expectancy by 2.1 years and 1.7 QALYs. At a base-case prevalence of 1.2%, once-per-lifetime screening cost $13,396 per QALY gained, exclusive of benefit from reduced transmission. Cost-effectiveness of screening remained favourable until prevalence dropped below 0.04%. When HIV-transmission-related costs and benefits were included, once-per-lifetime screening cost $6910 per QALY gained and screening every two years cost $27,696 per QALY gained. An important determinant of the cost-effectiveness of screening was effectiveness of counselling about risk reduction. Early identification of HIV infection through screening in Russia is effective and cost-effective in all but the lowest prevalence groups.

Screening women of childbearing age for human immunodeficiency virus. A cost-benefit analysis.

In light of the increasing problem of perinatal human immunodeficiency virus (HIV) transmission, the issue of screening women for HIV is receiving considerable attention. We analyzed the costs and benefits of screening women of childbearing age for HIV. The analysis was based on a dynamic model of the HIV epidemic that incorporated disease transmission and progression, behavioral changes, and effects of screening and counseling. We found that the primary benefit of screening programs targeted to women of childbearing age lies not in the prevention of HIV infection in their newborns but in the prevention of infection in their adult contacts. Because of this benefit, screening medium- and high-risk women is likely to be cost-beneficial over a wide range of assumptions about program cost and behavioral changes in response to screening.

The cost-effectiveness of buprenorphine maintenance therapy for opiate addiction in the United States.

AIMS: To determine the cost-effectiveness of buprenorphine maintenance therapy for opiate addiction in the United States, particularly its effect on the HIV epidemic. DESIGN: We developed a dynamic model to capture the effects of adding buprenorphine maintenance to the current opiate dependence treatment system. We evaluated incremental costs, including all health-care costs, and incremental effectiveness, measured as quality-adjusted life years (QALYs) of survival. We considered communities with HIV prevalence among injection drug users of 5% and 40%. Because no price has been set in the United States for a dose of buprenorphine, we considered three prices per dose: $5, $15, and $30. FINDINGS: If buprenorphine increases the number of individuals in maintenance treatment by 10%, but does not affect the number of individuals receiving methadone maintenance, the cost-effectiveness ratios for buprenorphine maintenance therapy are less than $45 000 per QALY gained for all prices, in both the low-prevalence and high-prevalence communities. If the same number of individuals enter buprenorphine maintenance (10% of the number currently in methadone), but half are injection drug users newly entering maintenance and half are individuals who switched from methadone to buprenorphine, the cost-effectiveness ratios in both communities are less than $45 000 per QALY gained for the $5 and $15 prices, and greater than $65 000 per QALY gained for the $30 price. CONCLUSIONS: At a price of $5 or less per dose, buprenorphine maintenance is cost-effective under all scenarios we considered. At $15 per dose, it is cost-effective if its adoption does not lead to a net decline in methadone use, or if a medium to high value is assigned to the years of life lived by injection drug users and those in maintenance therapy. At $30 per dose, buprenorphine will be cost-effective only under the most optimistic modeling assumptions.

The workup of the asymptomatic patient with a positive fecal occult blood test.

Twenty-two protocols for working up an asymptomatic patient who has a positive fecal occult blood test were evaluated using existing information on the prevalences of cancers, adenomas and other conditions in such patients; the natural history of colorectal cancer; the effectiveness of screening tests; risks; and costs. The authors estimate the impacts of the 22 workup strategies on outcomes such as the chance of finding an existing cancer or adenoma, risks (bleeding and perforation), and financial costs of different strategies involving rigid sigmoidoscopy, flexible sigmoidoscopy, barium enema, and colonoscopy. Two protocols were particularly effective. The first involves performing a barium enema study and following it with colonoscopy; if colonoscopy is negative, the barium enema study should be repeated. The second is to perform colonoscopy and if it is negative, follow it with a barium enema study.

Optimal investment in a portfolio of HIV prevention programs.

OBJECTIVES: In this article, the authors determine the optimal allocation of HIV prevention funds and investigate the impact of different allocation methods on health outcomes. METHODS: The authors present a resource allocation model that can be used to determine the allocation of HIV prevention funds that maximizes quality-adjusted life years (or life years) gained or HIV infections averted in a population over a specified time horizon. They apply the model to determine the allocation of a limited budget among 3 types of HIV prevention programs in a population of injection drug users and nonusers: needle exchange programs, methadone maintenance treatment, and condom availability programs. For each prevention program, the authors estimate a production function that relates the amount invested to the associated change in risky behavior. RESULTS: The authors determine the optimal allocation of funds for both objective functions for a high-prevalence population and a low-prevalence population. They also consider the allocation of funds under several common rules of thumb that are used to allocate HIV prevention resources. It is shown that simpler allocation methods (e.g., allocation based on HIV incidence or notions of equity among population groups) may lead to alloctions that do not yield the maximum health benefit. CONCLUSIONS: The optimal allocation of HIV prevention funds in a population depends on HIV prevalence and incidence, the objective function, the production functions for the prevention programs, and other factors. Consideration of cost, equity, and social and political norms may be important when allocating HIV prevention funds. The model presented in this article can help decision makers determine the health consequences of different allocations of funds.

An analysis of optimal resource allocation for prevention of infection with human immunodeficiency virus (HIV) in injection drug users and non-users.

Millions of dollars are spent annually to prevent infection with human immunodeficiency virus (HIV) without a thorough understanding of the most effective way to allocate these resources. The authors' objective was to determine the allocation of new resources among prevention programs targeted to a population of injection drug users (IDUs) and a population of non-injection drug users (non-IDUs) that would minimize the total number of incident cases of HIV infection over a given time horizon. They developed a dynamic model of HIV transmission in IDUs and non-IDUs and estimated the relationship between prevention program expenditures and reductions in HIV transmission. They evaluated three prevention programs: HIV testing with routine counseling, HIV testing with intensive counseling, and HIV testing and counseling linked to methadone maintenance programs. They modeled a low-risk IDU population (5% HIV prevalence) and a moderate-risk IDU population (10% HIV prevalence). For different available budgets, they determined the allocation of resources among the prevention programs and populations that would minimize the number of new cases of HIV infection over a five-year period, as well as the incremental value of additional prevention funds. The study framework provides a quantitative, systematic approach to funding programs to prevent HIV infection that accounts for HIV transmission dynamics, population size, and the costs and effectiveness of the interventions in reducing HIV transmission. The approach is general and can be used to evaluate a broader group of prevention programs and risk populations. This framework thus could enable policy makers and clinicians to identify a portfolio of programs that provide, collectively, the most benefit for a given budget.

Resource allocation for epidemic control over short time horizons.

We present a model for allocation of epidemic control resources among a set of interventions. We assume that the epidemic is modeled by a general compartmental epidemic model, and that interventions change one or more of the parameters that describe the epidemic. Associated with each intervention is a 'production function' that relates the amount invested in the intervention to values of parameters in the epidemic model. The goal is to maximize quality-adjusted life years gained or the number of new infections averted over a fixed time horizon, subject to a budget constraint. Unlike previous models, our model allows for interacting populations and non-linear interacting production functions and does not require a long time horizon. We show that an analytical solution to the model may be difficult or impossible to derive, even for simple cases. Therefore, we derive a method of approximating the objective functions. We use the approximations to gain insight into the optimal resource allocation for three problem instances. We also develop heuristics for solving the general resource allocation problem. We present results of numerical studies using our approximations and heuristics. Finally, we discuss implications and applications of this work.

A patient mix model for hospital financial planning.

A linear programming model was formulated to examine the impact on hospital finances and resource use of changes in patient mix under current and proposed government reimbursement regulations. The model specifically incorporated the costs, revenues, and resource consumption patterns associated with patients drawn from different intensity level and payer class combinations. The necessary data were obtained from financial reports and other records, and the model was used in policy analysis at a major university teaching hospital.

Assessing effectiveness and cost-effectiveness of concurrency reduction for HIV prevention.

We estimated the effectiveness and cost-effectiveness of changes in concurrent sexual partnerships in reducing the spread of HIV in sub-Saharan Africa. Using data from Swaziland, Tanzania, Uganda and Zambia, we estimated country-specific concurrency behaviour from sexual behaviour survey data on the number of partners in the past 12 months, and we developed a network model to compare the impact of three behaviour changes on the HIV epidemic: (1) changes in concurrent partnership patterns to strict monogamy; (2) partnership reduction among those with the greatest number of partners; and (3) partnership reduction among all individuals. We estimated the number of new HIV infections over 10 years and the cost per infection averted. Given our assumptions and model structure, we find that reducing concurrency among high-risk individuals averts the most infections and increasing monogamy the least (11.7% versus 8.7% reduction in new infections, on average, for a 10% reduction in concurrent partnerships). A campaign that costs US$1 per person annually is likely cost-saving if it reduces concurrency by 9% on average, given our baseline estimates of concurrency. In sensitivity analysis, the rank ordering of behaviour change scenarios was unaffected by potential over-estimation of concurrency, though the number of infections averted decreased and the cost per HIV infection averted increased. Concurrency reduction programmes may be effective and cost-effective in reducing HIV incidence in sub-Saharan Africa if they can achieve even modest impacts at similar costs to past mass media campaigns in the region. Reduced concurrency among high-risk individuals appears to be most effective in reducing HIV incidence, but concurrency reduction in other risk groups may yield nearly as much benefit.

AIDS policy modeling for the 21st century: an overview of key issues.

Decisions about HIV prevention and treatment programs are based on factors such as program costs and health benefits, social and ethical issues, and political considerations. AIDS policy models--that is, models that evaluate the monetary and non-monetary consequences of decisions about HIV/AIDS interventions--can play a role in helping policy makers make better decisions. This paper provides an overview of the key issues related to developing useful AIDS policy models. We highlight issues of importance for researchers in the field of AIDS policy modeling as well as for policy makers. These include geographic area, setting, target groups, interventions, affordability and effectiveness of interventions, type and time horizon of policy model, and type of economic analysis. This paper is not intended to be an exhaustive review of the AIDS policy modeling literature, although many papers from the literature are discussed as examples; rather, we aim to convey the composition, achievements, and challenges of AIDS policy modeling.

HIV transmission and the cost-effectiveness of methadone maintenance.

OBJECTIVES: This study determined the cost-effectiveness of expanding methadone maintenance treatment for heroin addiction, particularly its effect on the HIV epidemic. METHODS: We developed a dynamic epidemic model to study the effects of increased methadone maintenance capacity on health care costs and survival, measured as quality-adjusted life-years (QALYs). We considered communities with HIV prevalence among injection drug users of 5% and 40%. RESULTS: Additional methadone maintenance capacity costs $8200 per QALY gained in the high-prevalence community and $10,900 per QALY gained in the low-prevalence community. More than half of the benefits are gained by individuals who do not inject drugs. Even if the benefits realized by treated and untreated injection drug users are ignored, methadone maintenance expansion costs between $14,100 and $15,200 per QALY gained. Additional capacity remains cost-effective even if it is twice as expensive and half as effective as current methadone maintenance slots. CONCLUSIONS: Expansion of methadone maintenance is cost-effective on the basis of commonly accepted criteria for medical interventions. Barriers to methadone maintenance deny injection drug users access to a cost-effective intervention that generates significant health benefits for the general population.

The cost effectiveness of voluntary prenatal and routine newborn HIV screening in the United States.

OBJECTIVE: To evaluate the cost effectiveness of voluntary prenatal and routine postnatal HIV screening in the cohort of pregnant women and newborns in the United States. DESIGN: Cost-effectiveness analysis. We developed a decision model to analyze the cost effectiveness of enhanced prenatal screening and routine newborn screening for HIV. We also analyzed the incremental cost effectiveness of routine newborn screening when improved voluntary prenatal screening is already in place. PARTICIPANTS: Analysis of the cohort of pregnant women and newborns in the United States. INTERVENTIONS: Enhanced prenatal screening, or routine newborn screening for HIV. MAIN OUTCOME MEASURES: Infections averted, life expectancy, costs, and incremental cost effectiveness. RESULTS: Improved participation in voluntary prenatal HIV screening would result in an additional 1.1 million women being screened annually, would identify an additional 527 HIV-infected mothers annually, would avert 150 infections in newborns, and would cost $8,900 U.S. per life-year gained. Routine newborn HIV screening would test 3.9 million infants annually, would identify 1061 HIV-infected mothers, would avert 266 infections in newborns, and would cost $7,000 U.S. per life-year gained. If improved voluntary prenatal screening is already in place, routine newborn screening would avert an additional 135 infections in newborns, at an incremental cost of $10, 600 U.S. per life-year gained. The screening programs are likely to be cost effective over a wide range of assumptions regarding key factors in the analysis. CONCLUSIONS: Improved voluntary prenatal HIV screening of women and routine screening of newborns are cost effective. Routine newborn screening becomes less attractive as the rate of voluntary prenatal screening increases. Improved participation in voluntary prenatal screening has the added benefit that mothers maintain their right to determine whether they are tested for HIV.