Background: Although the number of infected people receiving highly active anti-retroviral therapy (HAART) in low- and middle- income countries increased dramatically, optimal disease management is not well defined.

Methods: We developed a model to compare the costs and benefits of three types of Human Immunodeficiency Virus monitoring strategies: symptom-based strategies, CD4-based strategies, and CD4 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 to the symptom-based approaches, monitoring CD4 every 6 months and starting treatment at a threshold of 200 cells/μl was associated with a life expectancy gain of 6.5 months (61.9 vs. 68.4) and a discounted lifetime cost savings of $464 per person (4,069 vs. 3,605 discounted 2007 USD). CD4-based strategies where treatment was started at the higher threshold of 350 cells/μl provided an additional life expectancy gain of 5.3 months at a cost effectiveness of $107 per life-year gained compared to a threshold of 200 cells/μl. Monitoring viral load with CD4 was more expensive than monitoring CD4 alone, added 2.0 months of life, and had an incremental cost-effectiveness ratio of $5,414/life-year gained relative to monitoring CD4 counts. In sensitivity analyses, the cost-savings from CD4 monitoring compared to 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 HAART initiation 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.

Objective
Inadequate adherence to highly active antiretroviral therapy (HAART) may lead to poor health outcomes and the development of HIV strains that are resistant to HAART. The authors developed a model to evaluate the cost-effectiveness of counseling interventions to improve adherence to HAART among men who have sex with men (MSM).

Methods
The authors developed a dynamic compartmental model that incorporates HIV treatment, adherence to treatment, and infection transmission and progression. All data estimates were obtained from secondary sources. The authors evaluated a counseling intervention given prior to initiation of HAART and before all changes in drug regimens, combined with phone-in support while on HAART. They considered a moderate-prevalence and a high-prevalence population of MSM.

Results
If the impact of HIV transmission is ignored, the counseling intervention has a cost-effectiveness ratio of $25,500 per quality-adjusted life year (QALY) gained. When HIV transmission is included, the cost-effectiveness ratio is much lower: $7400 and $8700 per QALY gained in the moderate- and high-prevalence populations, respectively. When the intervention is twice as costly per counseling session and half as effective as estimated in the base case (in terms of the number of individuals who become highly adherent, and who remain highly adherent), then the intervention costs $17,100 and $19,600 per QALY gained in the 2 populations, respectively.

Conclusions
Counseling to improve adherence to HAART increased length of life, modestly reduced HIV transmission, and cost substantially less than $50,000 per QALY gained over a wide range of assumptions but did not reduce the proportion of drug-resistant strains. Such counseling provides only modest benefit as a tool for HIV prevention but can provide significant benefit for individual patients at an affordable cost.

OBJECTIVES: We sought to determine the prevalence of HIV in both inpatient and outpatient settings in 6 Department of Veterans Affairs (VA) health care sites. METHODS: We collected demographic data and data on comorbid conditions and then conducted blinded, anonymous HIV testing. We conducted a multivariate analysis to determine predictors of HIV infection. RESULTS: We tested 4500 outpatient blood specimens and 4205 inpatient blood specimens; 326 (3.7%) patients tested positive for HIV. Inpatient HIV prevalence ranged from 1.2% to 6.9%; outpatient HIV prevalence ranged from 0.9% to 8.9%. Having a history of hepatitis B or C infection, a sexually transmitted disease, or pneumonia also predicted HIV infection. The prevalence of previously undocumented HIV infection varied from 0.1% to 2.8% among outpatients and from 0.0% to 1.7% among inpatients. CONCLUSIONS: The prevalence of undocumented HIV infection was sufficiently high for routine voluntary screening to be cost effective in each of the 6 sites we evaluated. Many VA health care systems should consider expanded routine voluntary HIV screening.

OBJECTIVES: To determine whether gaps exist in published cost-utility analyses as measured by their coverage of topics addressed in current HIV guidelines from the Department of Health and Human Services (DHHS).

DESIGN: A systematic review of US-based cost-effectiveness analyses of HIV/AIDS prevention and management strategies, based on original, published research.

METHODS: Predefined criteria were used to identify all analyses pertaining to prevention and management of HIV/AIDS; information was collected on type of strategy, patient demographics, study perspective, quality of the study, effectiveness measures, costs, and cost-effectiveness ratios.

RESULTS: One hundred and six studies were identified; 62 described strategies for averting new HIV infections, and 44 dealt with managing persons who are HIV positive. The quality of studies was generally high, but gaps were found in all studies. Especially common were omissions in reporting data abstraction methodology and discussions of direction and magnitude of potential biases. Among the 22 most highly rated papers (score of 90 or higher), only 1 was cited in the guidelines, and 3 papers reported on interventions that were superseded by newer approaches. Using a USD 100,000 threshold, the guidelines usually endorsed interventions found to be cost-effective. Exceptions included recommending postexposure prophylaxis (PEP) for populations in which PEP is unlikely to be cost-effective and not recommending primary resistance testing in treatment-naive persons, although the intervention was reported to have a cost-effectiveness ratio of less than USD 50,000.

CONCLUSIONS: Despite an abundant literature on the cost-utility of HIV/AIDS-targeted strategies, guidelines cite relatively few of these papers, and gaps exist regarding assessments of some strategies and special populations.

To analyze temporal patterns of antiretroviral (ARV) prescribing practices relative to nationally defined guidelines in treatment-naive patients with HIV-1 infection. DESIGN: Retrospective cohort study. METHODS: We evaluated ARV prescribing patterns among ARV treatment-naive veterans who were receiving care within the US Department of Veterans Affairs (VA) from 1992 through 2004 in comparison to evolving adult HIV-1 treatment guidelines. RESULTS: A total of 15,934 patients initiated ARV treatment. Since 1999, >94% of patients initiated at least a 3-ARV medication combination, although the percentage of patients who initiated a guideline "preferred" or "alternative" regimen never rose to greater than 72% and was significantly associated with being black and with region of care. After 1999, 20% of patients started 4 or more active ARV agents in combination, which was significantly associated with lower baseline CD4 cell count, higher viral load, and receiving care in the western United States. The proportion of patients receiving guideline "not recommended" regimens (virologically undesirable or overlapping toxicities) was <1% after 1997. VA prescribing trends generally predated guideline recommendations by 6 to 12 months. CONCLUSIONS: VA prescribing patterns for ARV initiation adhere to treatment guidelines that maximize safety. Guidelines designed to maximize efficacy were not followed as stringently. Evaluating clinical practice patterns against contemporary treatment guidelines can inform guideline development.

We developed a mathematical model to simulate the impact of various partially effective preventive HIV vaccination scenarios in a population at high risk for heterosexually transmitted HIV. We considered an adult population defined by gender (male/female), disease stage (HIV-negative, HIV-positive, AIDS, and death), and vaccination status (unvaccinated/vaccinated) in Soweto, South Africa. Input data included initial HIV prevalence of 20% (women) and 12% (men), vaccination coverage of 75%, and exclusive male negotiation of condom use.

We explored how changes in vaccine efficacy and postvaccination condom use would affect HIV prevalence and total HIV infections prevented over a 10-year period. In the base-case scenario, a 40% effective HIV vaccine would avert 61,000 infections and reduce future HIV prevalence from 20% to 13%. A 25% increase (or decrease) in condom use among vaccinated individuals would instead avert 75,000 (or only 46,000) infections and reduce the HIV prevalence to 12% (or only 15%). Furthermore, certain combinations of increased risk behavior and vaccines with <43% efficacy could worsen the epidemic. Even modestly effective HIV vaccines can confer enormous benefits in terms of HIV infections averted and decreased HIV prevalence. However, programs to reduce risk behavior may be important components of successful vaccination campaigns.

Background: HIV prevention funds are often allocated by decision makers at multiple levels. High-level decision makers may allocate funds to regions, and regional decision makers then allocate those funds to specific programs. Often, funds are allocated proportionally (e.g., in proportion to HIV incidence) rather than efficiently (i.e., to maximize HIV infections averted). The authors investigate the impact of efficient and proportional allocation methods at 2 different decision levels.

Methods: The authors developed an optimization model of resource allocation at 2 levels-an aggregate upper level and multiple local levels-and considered efficient allocation and allocation proportional to HIV incidence. Using data from 40 U.S. states, they compared 4 strategies for allocating HIV prevention funds.

Results: The greatest health benefit (HIV infections averted) occurred when efficient allocations were made at both levels. When funds were allocated proportionally at the higher level and efficiently at the lower level, the health benefit was about 5% less than when efficient allocations were made at both levels. When funds were allocated efficiently at the higher level and proportionally at the lower level, the health benefit was 15% less than when efficient allocations were made at both levels. The least health benefit (23% less than when efficient allocations were made at both levels) occurred with proportional allocation at both levels.

Conclusions: Efficient allocation only at the higher level cannot overcome poor allocations at lower levels. Moreover, efficient allocation at the lower level is likely to yield greater gains than efficient allocation at the higher level. Thus, upper-level decision makers, such as donor organizations, should develop incentives to promote efficient allocation by lower-level decision makers.

This issue of CHP/PCOR's Quarterly Update covers news from the Spring 2007 quarter and includes articles about:

• the HIV/AIDS International Conference in St. Petersburg, Russia, that was attended by the CHP/PCOR National Institute on Drug Abuse project team;
• a special international health section that highlights HIV/AIDS research in Zimbabwe, and two Payne lecturer talks, given by David Heymann and Peter Piot, speaking on infectious diseases and HIV/AIDS, respectively;
• two Research in Brief selections -- one highlights health care financing structures in high-income countries, and the second covers an ongoing trial that incorporates a smoking cessation program into posttraumatic stress disorder treatment at the VA;
• a Staff Spotlight feature on new CHP/PCOR core faculty member Sally Horwitz;
• two conferences -- one hosted by the Stanford International Initiative and the other a National Summit on America's Children at the Capitol.

This issue of CHP/PCOR's Quarterly Update covers news from the Winter 2007 quarter and includes articles about:

• two Veterans Affairs-related items -- this year's recipient of the Under Secretary's Award for Health Science Research, and the Health Services Research & Development Annual meeting;
• the importance of proper HIV resource allocation: What method of allocation is best to ensure that HIV prevention and treatment program funds are being used effectively? One study looks at this issue from an aggregate-level analysis;
• the use of functional magnetic resonance imaging technology to examine how financial decisions are made. Researchers were able to identify specific areas of the brain that are activated prior to when individuals actually make purchasing decisions;
• the report series concerning the quality gap, as identified by the Institute of Medicine. Two recently-released reports about the quality gap in asthma care and healthcare-associated infections are covered;
• CHP/PCOR research activities and updates, including a year-in-review of the Patient Safety Research Group that examines the notion of safety culture;
• a Research in Brief selection that highlights recently-published CHP/PCOR research. This piece examines the public-private partnerships model used to improve health and welfare systems.