This issue of CHP/PCOR's quarterly newsletter covers news and developments from the winter 2004 quarter. It features articles about:

• a widely publicized study by CHP/PCOR researchers which found that routine HIV screening is cost-effective and would extend the lives of HIV-positive patients;
• publication of the first three volumes of "Closing the Quality Gap," a report prepared by researchers at CHP/PCOR and UCSF that evaluates quality improvement strategies for specific medical conditions;
• a health vouchers plan co-authored by Victor Fuchs, which would provide comprehensive health coverage for all Americans, while maintaining individual choice and free-market competition;
• a research collaboration led by CHP/PCOR that has been awarded a grant to develop a comprehensive Medicare reform plan; and
• the work of former CHP/PCOR trainee Jessica Haberer, who is doing HIV/AIDS research in China for the William J. Clinton foundation, and recently met the former president in this capacity.

Background: Although the Centers for Disease Control and Prevention (CDC) recommend routine HIV counseling, testing, and referral (HIVCTR) in settings with at least a 1 percent prevalence of HIV, roughly 280,000 Americans are unaware of their human immunodeficiency virus (HIV) infection. The effect of expanded screening for HIV is unknown in the era of effective antiretroviral therapy.

Methods: We developed a computer simulation model of HIV screening and treatment to compare routine, voluntary HIVCTR with current practice in three target populations: "high-risk" (3.0 percent prevalence of undiagnosed HIV infection; 1.2 percent annual incidence); "CDC threshold" (1.0 percent and 0.12 percent, respectively); and "U.S. general" (0.1 percent and 0.01 percent). Input data were derived from clinical trials and observational cohorts. Outcomes included quality-adjusted survival, cost, and cost-effectiveness.

Results: In the high-risk population, the addition of one-time screening for HIV antibodies with an enzyme-linked immunosorbent assay (ELISA) to current practice was associated with earlier diagnosis of HIV (mean CD4 cell count at diagnosis, 210 vs. 154 per cubic millimeter). One-time screening also improved average survival time among HIV-infected patients (quality-adjusted survival, 220.7 months vs. 219.8 months). The incremental cost-effectiveness was $36,000 per quality-adjusted life-year gained. Testing every five years cost $50,000 per quality-adjusted life-year gained, and testing every three years cost $63,000 per quality-adjusted life-year gained. In the CDC threshold population, the cost-effectiveness ratio for one-time screening with ELISA was $38,000 per quality-adjusted life-year gained, whereas testing every five years cost $71,000 per quality-adjusted life-year gained, and testing every three years cost $85,000 per quality-adjusted life-year gained. In the U.S. general population, one-time screening cost $113,000 per quality-adjusted life-year gained.

Conclusions: In all but the lowest-risk populations, routine, voluntary screening for HIV once every three to five years is justified on both clinical and cost-effectiveness grounds. One-time screening in the general population may also be cost-effective.

Background:

The costs, benefits, and cost-effectiveness of screening for human immunodeficiency virus (HIV) in health care settings during the era of highly active antiretroviral therapy (HAART) have not been determined.

Methods:

We developed a Markov model of costs, quality of life, and survival associated with an HIV-screening program as compared with current practice. In both strategies, symptomatic patients were identified through symptom-based case finding. Identified patients started treatment when their CD4 count dropped to 350 cells per cubic millimeter. Disease progression was defined on the basis of CD4 levels and viral load. The likelihood of sexual transmission was based on viral load, knowledge of HIV status, and efficacy of counseling.

Results:

Given a 1 percent prevalence of unidentified HIV infection, screening increased life expectancy by 5.48 days, or 4.70 quality-adjusted days, at an estimated cost of $194 per screened patient, for a cost-effectiveness ratio of $15,078 per quality-adjusted life-year. Screening cost less than $50,000 per quality-adjusted life-year if the prevalence of unidentified HIV infection exceeded 0.05 percent. Excluding HIV transmission, the cost-effectiveness of screening was $41,736 per quality-adjusted life-year. Screening every five years, as compared with a one-time screening program, cost $57,138 per quality-adjusted life-year, but was more attractive in settings with a high incidence of infection. Our results were sensitive to the efficacy of behavior modification, the benefit of early identification and therapy, and the prevalence and incidence of HIV infection.

Conclusions:

The cost-effectiveness of routine HIV screening in health care settings, even in relatively low-prevalence populations, is similar to that of commonly accepted interventions, and such programs should be expanded.

The UN has launched an initiative to place 3 million people in developing countries on antiretroviral AIDS treatment by end 2005 (the 3 by 5 target). Lessons for HIV/AIDS treatment scale-up emerge from recent experience with multidrug-resistant tuberculosis. Expansion of treatment for multidrug-resistant tuberculosis through the multipartner mechanism known as the Green Light Committee (GLC) has enabled gains in areas relevant to 3 by 5, including policy development, drug procurement, rational use of drugs, and the strengthening of health systems. The successes of the GLC and the obstacles it has encountered provide insights for building sustainable HIV/AIDS treatment programmes.

This study examined factors affecting medical service use among HIV-infected persons with a substance abuse disorder. The sample comprised 190 participants enrolled in a randomized trial of a case management intervention. Participants were interviewed about their backgrounds, housing status, income, alcohol and drug use problems, health status and depressive symptoms at study entry. Electronic medical records were used to assess medical service use. Poisson regression models were tested to determine the effects of need, enabling and predisposing factors on the dependent variables of emergency department visits, inpatient admissions and ambulatory care visits. During a two-year period, 71% were treated in the emergency department, 64% had been hospitalized and the sample averaged 12.9 ambulatory care visits. Homelessness was associated with higher utilization of emergency department and inpatient services; drug use severity was associated with higher inpatient and ambulatory care service use; and alcohol use severity was associated with greater use of emergency medical services. Homelessness and substance abuse exacerbate the health care needs of HIV-infected persons and result in increased use of emergency department and inpatient services. Interventions are needed that target HIV-infected persons with substance abuse disorders, particularly those that increase entry and retention in outpatient health care and thus decrease reliance on acute hospital-based services.

The success of clinical decision-support systems requires that they are seamlessly integrated into clinical workflow. In the SAGE project, which aims to create the technological infra-structure for implementing computable clinical practice guide-lines in enterprise settings, we created a deployment-driven methodology for developing guideline knowledge bases. It involves (1) identification of usage scenarios of guideline-based care in clinical workflow, (2) distillation and disambiguation of guideline knowledge relevant to these usage scenarios, (3) formalization of data elements and vocabulary used in the guideline, and (4) encoding of usage scenarios and guideline knowledge using an executable guideline model. This methodology makes explicit the points in the care process where guideline-based decision aids are appropriate and the roles of clinicians for whom the guideline-based assistance is intended. We have evaluated the methodology by simulating the deployment of an immunization guideline in a real clinical information system and by reconstructing the workflow context of a deployed decision-support system for guideline-based care. We discuss the implication of deployment-driven guideline encoding for sharability of executable guidelines.

Secondary life insurance markets are growing rapidly. Fromnearly no transactions

in 1980, a wide variety of similar products in this market has developed,

including viatical settlements, accelerated death benefits, and life

settlements and as the population ages, these markets will become increasingly

popular. Eight state governments, in a bid to guarantee sellers a "fair"

price, have passed regulations setting a price floor on secondary life insurance

market transactions, and more are considering doing the same. Using

data from a unique random sample of HIV+ patients, we estimate welfare

losses from transactions prevented by binding price floors in the viatical

settlements market (an important segment of the secondary life insurance

market). We find that price floors bind on HIV patients with greater than

4 years of life expectancy. Furthermore, HIV patients from states with price

floors are significantly less likely to viaticate than similarly healthy HIV patients from other states. If price floors were adopted nationwide, they would

rule out transactions worth $119 million per year. We find that the magnitude

of welfare loss from these blocked transactions would be highest for

consumers who are relatively poor, have weak bequest motives, and have a

high rate of time preference.

This issue of CHP/PCOR's quarterly newsletter covers news and developments from the spring 2004 quarter.

It features articles about: our new core faculty member Paul Wise, a children's health policy researcher who joins us from Boston University; a survey of patient safety culture now getting underway at hospitals nationwide; CHP/PCOR acting director Doug Owens' research findings on the cost-effectiveness of potential HIV vaccines; a wrap-up of the second annual Health Care Quality and Outcomes Research Conference, where CHP/PCOR faculty and trainees attended and presented research; and new CHP/PCOR assistant director Vandana Sundaram.

In a random assignment study, substance-abusing patients with HIV/AIDS in a public general hospital received a brief contact condition or received 12 months of case management delivered by paraprofessionals. Patient outcomes included substance use, HIV transmission risk, physical health, psychological status, and quality of living situation. In both conditions, a significant decrease occurred in a range of problems from Intake to the 6-month interview, followed by no significant pattern of change at 12- and 18-month interviews. On major outcome variables, there were no significant differences between the brief contact and case management conditions. Sixteen percent had died by the 18-month interview. Process data indicated wide variation in the amount of case management received by participants, and the amount of case management was not related to improvement in the outcome measures. The study has limitations yet does not support the hypothesis that case management improves outcomes better than brief contact for this population.

Traditional cost-effectiveness analysis (CEA) assumes that program costs and benefits scale linearly with investment-an unrealistic assumption for epidemic control programs. This paper combines epidemic modeling with optimization techniques to determine the optimal allocation of a limited resource for epidemic control among multiple noninteracting populations. We show that the optimal resource allocation depends on many factors including the size of each population, the state of the epidemic in each population before resources are allocated (e.g. infection prevalence and incidence), the length of the time horizon, and prevention program characteristics. We establish conditions that characterize the optimal solution in certain cases.