Abstract

BACKGROUND:

Although recent guidelines call for expanded routine screening for HIV, resources for antiretroviral therapy (ART) are limited, and all eligible persons are not currently receiving treatment.

OBJECTIVE:

To evaluate the effects on the U.S. HIV epidemic of expanded ART, HIV screening, or interventions to reduce risk behavior.

DESIGN:

Dynamic mathematical model of HIV transmission and disease progression and cost-effectiveness analysis.

DATA SOURCES:

Published literature.

TARGET POPULATION:

High-risk (injection drug users and men who have sex with men) and low-risk persons aged 15 to 64 years in the United States.

TIME HORIZON:

Twenty years and lifetime (costs and quality-adjusted life-years [QALYs]).

PERSPECTIVE:

Societal.

INTERVENTION:

Expanded HIV screening and counseling, treatment with ART, or both.

OUTCOME MEASURES:

New HIV infections, discounted costs and QALYs, and incremental cost-effectiveness ratios.

RESULTS OF BASE-CASE ANALYSIS:

One-time HIV screening of low-risk persons coupled with annual screening of high-risk persons could prevent 6.7% of a projected 1.23 million new infections and cost $22,382 per QALY gained, assuming a 20% reduction in sexual activity after screening. Expanding ART utilization to 75% of eligible persons prevents 10.3% of infections and costs $20,300 per QALY gained. A combination strategy prevents 17.3% of infections and costs $21,580 per QALY gained.

RESULTS OF SENSITIVITY ANALYSIS:

With no reduction in sexual activity, expanded screening prevents 3.7% of infections. Earlier ART initiation when a CD4 count is greater than 0.350 × 10(9) cells/L prevents 20% to 28% of infections. Additional efforts to halve high-risk behavior could reduce infections by 65%.

LIMITATION:

The model of disease progression and treatment was simplified, and acute HIV screening was excluded.

CONCLUSION:

Expanding HIV screening and treatment simultaneously offers the greatest health benefit and is cost-effective. However, even substantial expansion of HIV screening and treatment programs is not sufficient to markedly reduce the U.S. HIV epidemic without substantial reductions in risk behavior.

PRIMARY FUNDING SOURCE:

National Institute on Drug Abuse, National Institutes of Health, and Department of Veterans Affairs.

Abstract

As human life expectancy continues to rise, financial decisions of aging investors may have an increasing impact on the global economy. In this study, we examined age differences in financial decisions across the adult life span by combining functional neuroimaging with a dynamic financial investment task. During the task, older adults made more suboptimal choices than younger adults when choosing risky assets. This age-related effect was mediated by a neural measure of temporal variability in nucleus accumbens activity. These findings reveal a novel neural mechanism by which aging may disrupt rational financial choice.

We explore whether HIV stigma is associated with seeking to conceal testing interest. We examine 86,899 outpatient visits in a 1993-1997 national survey and compare HIV testing to four non-stigmatized tests: spirometry, allergy testing, mammography, and colonoscopy. We explore whether people testing for HIV, compared to people receiving control services, listed reasons for visit (RFV) less related to the test performed, listed their interest in testing more frequently as a non-primary RFV, and received more services unrelated to testing. A total of 48.7% of people tested for HIV listed a reason unrelated to testing as their primary RFV (spirometry: 8.9%; allergy testing: 29.3%), and 69.9% of people asking to test requested HIV testing as a secondary RFV (spirometry: 52%; allergy testing: 0%). People who tested for HIV received more services (M=1.83 additional services) than non-testers (M=0.95) on an index of seven services. We did not find this association for spirometry, allergy testing, colonoscopy, or mammography. We interpret these results to indicate that stigma may have behavioral correlates and that people may attempt to avoid HIV stigma by seeking a psychological cover for HIV testing. To our knowledge, this is the first study to attempt to use observational data on health service usage for assessing stigma and people's attempts to deal with HIV testing stigma.

Chronic viral diseases such as human immunodeficiency virus (HIV) and hepatitis B virus (HBV) afflict millions of people worldwide. A key public health challenge in managing such diseases is identifying infected, asymptomatic individuals so that they can receive antiviral treatment. Such treatment can benefit both the treated individual (by improving quality and length of life) and the population as a whole (through reduced transmission). We develop a compartmental model of a chronic, treatable infectious disease and use it to evaluate the cost and effectiveness of different levels of screening and contact tracing.

We show that:

1. the optimal strategy is to get infected individuals into treatment at the maximal rate until the incremental health benefits balance the incremental cost of controlling the disease;
   
2. as one reduces the disease prevalence by moving people into treatment (which decreases the chance that they will infect others), one should increase the level of contact tracing to compensate for the decreased effectiveness of screening;
   
3. as the disease becomes less prevalent, it is optimal to spend more per case identified; and
   
4. the relative mix of screening and contact tracing at any level of disease prevalence is such that the marginal efficiency of contact tracing (cost per infected person found) equals that of screening if possible (e.g., when capacity limitations are not binding).
   

We also show how to determine the costeffective equilibrium level of disease prevalence (among untreated individuals), and we develop an approximation of the path of the optimal prevalence over time. Using this, one can obtain a close approximation of the optimal solution without having to solve an optimal control problem. We apply our methods to an example of hepatitis B virus.

Objective To determine the association of reductions in price of antiretroviral drugs and foreign assistance for HIV with coverage of antiretroviral treatment.

Design Retrospective study.

Setting Africa.

Participants 13 African countries, 2003-8.

Main outcome measures A price index of first line antiretroviral therapy with data on foreign assistance for HIV was used to estimate the associations of prices and foreign assistance with antiretroviral coverage (percentage of people with advanced HIV infection receiving antiretroviral therapy), controlling for national public health spending, HIV prevalence, governance, and fixed effects for countries and years.

Results Between 2003 and 2008 the annual price of first line antiretroviral therapy decreased from $1177 (£733; €844) to $96 and foreign assistance for HIV per capita increased from $0.4 to $13.8. At an annual price of $100, a $10 decrease was associated with a 0.16% adjusted increase in coverage (95% confidence interval 0.11% to 0.20%; 0.19% unadjusted, 0.14% to 0.24%). Each additional $1 per capita in foreign assistance for HIV was associated with a 1.0% adjusted increase in coverage (0.7% to 1.2%; 1.4% unadjusted, 1.1% to 1.6%). If the annual price of antiretroviral therapy stayed at $100, foreign assistance would need to quadruple to $64 per capita to be associated with universal coverage. Government effectiveness and national public health expenditures were also positively associated with increasing coverage.

Conclusions Reductions in price of antiretroviral drugs were important in broadening coverage of HIV treatment in Africa from 2003 to 2008, but their future role may be limited. Foreign assistance and national public health expenditures for HIV seem more important in expanding future coverage.

Study objective: We describe the availability of preventive health services in US emergency departments (EDs), as well as ED directors' preferred service and perceptions of barriers to offering preventive services.

Methods: Using the 2007 National Emergency Department Inventory (NEDI)-USA, we randomly sampled 350 (7%) of 4,874 EDs. We surveyed directors of these EDs to determine the availability of

1. screening and referral programs for alcohol, tobacco, geriatric falls, intimate partner violence, HIV, diabetes, and hypertension;
   
2. vaccination programs for influenza and pneumococcus; and
   
3. linkage programs to primary care and health insurance.
   

ED directors were asked to select the service they would most like to implement and to rate 5 potential barriers to offering preventive services.

Results: Two hundred seventy-seven EDs (80%) responded across 46 states. Availability of services ranged from 66% for intimate partner violence screening to 19% for HIV screening. ED directors wanted to implement primary care linkage most (17%) and HIV screening least (2%). ED directors "agreed/strongly agreed" that the following are barriers to ED preventive care: cost (74%), increased patient length of stay (64%), lack of follow-up (60%), resource shifting leading to worse patient outcomes (53%), and philosophical opposition (27%).

Conclusion: Most US EDs offer preventive services, but availability and ED director preference for type of service vary greatly. The maj ority of EDs do not routinely offer Centers for Disease Control and Prevention- recommended HIV screening. Most ED directors are not philosophically opposed to offering preventive services but are concerned with added costs, effects on ED operations, and potential lack of follow- up.

Circumcision significantly reduces female-to-male transmission of HIV infection, but changes in behavior may influence the overall impact on transmission. We sought to explore these effects, particularly for societies where women have less power to negotiate safe sex. We developed a compartmental epidemic model to simulate the population-level impact of various circumcision programs on heterosexual HIV transmission in Soweto. We incorporated gender-specific negotiation of condom use in sexual partnerships and explored post-circumcision changes in condom use. A 5-year prevention program in which only an additional 10% of uncircumcised males undergo circumcision each year, for example, would prevent 13% of the expected new HIV infections over 20 years. Outcomes were sensitive to potential changes in behavior and differed by gender. For Southern Africa, even modest programs offering circumcision would result in significant benefits. Because decreases in male condom use could diminish these benefits, particularly for women, circumcision programs should emphasize risk-reduction counseling.

BACKGROUND: Universal testing and treatment holds promise for reducing the burden of human immunodeficiency virus (HIV) in sub-Saharan Africa, but linkage from testing to treatment sites and retention in care are inadequate.

METHODS: We developed a simulation of the HIV epidemic and HIV disease progression in South Africa to compare the outcomes of the present HIV treatment campaign (status quo) with 4 HIV testing and treating strategies that increase access to antiretroviral therapy: (1) universal testing and treatment without changes in linkage to care and loss to follow-up; (2) universal testing and treatment with improved linkage to care; (3) universal testing and treatment with reduced loss to follow-up; and (4) comprehensive HIV care with universal testing and treatment, improved linkage to care, and reduced loss to follow-up. The main outcome measures were survival benefits, new HIV infections, and HIV prevalence. 

RESULTS: Compared with the status quo strategy, universal testing and treatment (1) was associated with a mean (95% uncertainty bounds) life expectancy gain of 12.0 months (11.3-12.2 months), and 35.3% (32.7%-37.5%) fewer HIV infections over a 10-year time horizon. Improved linkage to care (2), prevention of loss to follow-up (3), and comprehensive HIV care (4) provided substantial additional benefits: life expectancy gains compared with the status quo strategy were 16.1, 18.6, and 22.2 months, and new infections were 55.5%, 51.4%, and 73.2% lower, respectively. In sensitivity analysis, comprehensive HIV care reduced new infections by 69.7% to 76.7% under a broad set of assumptions.

CONCLUSIONS: Universal testing and treatment with current levels of linkage to care and loss to follow-up could substantially reduce the HIV death toll and new HIV infections. However, increasing linkage to care and preventing loss to follow-up provides nearly twice the benefits of universal testing and treatment alone.