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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.

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Am J Public Health
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Douglas K. Owens
Mark Holodniy
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Background: This chapter of the guidelines is intended to provide an evidence-based assessment of the initial evaluation of patients recognized as having lung cancer and the recognition of paraneoplastic syndromes.

Methods: The current medical literature that is applicable to this issue was identified by a computerized search and was evaluated using standardized methods. Recommendations were framed using the approach described by the Health and Science Policy Committee of the American College of Chest Physicians.

Results: Patients with lung cancer usually present with multiple symptoms, both respiratory related and constitutional. There is usually a time delay between symptom recognition by the patient and the ultimate diagnosis of lung cancer by the physician. Whether this time delay impacts prognosis is unclear, but delivering timely and efficient care is an important component in its own right. Lung cancer may be accompanied by a variety of paraneoplastic syndromes. These syndromes may not necessarily preclude treatment with a curative intent.

Conclusions: The initial evaluation of the patient with known or suspected lung cancer should include an assessment of symptoms, signs, and laboratory test results in a standardized manner as a screen for identifying those patients with paraneoplastic syndromes and a higher likelihood of metastatic disease.

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Background: Correctly staging lung cancer is important because the treatment options and the prognosis differ significantly by stage. Several noninvasive imaging studies including chest CT scanning and positron emission tomography (PET) scanning are available. Understanding the test characteristics of these noninvasive staging studies is critical to decision making.

Methods: Test characteristics for the noninvasive staging studies were updated from the first iteration of the lung cancer guidelines using systematic searches of the MEDLINE, HealthStar, and Cochrane Library databases up to May 2006, including selected metaanalyses, practice guidelines, and reviews. Study designs and results are summarized in evidence tables.

Results: The pooled sensitivity and specificity of CT scanning for identifying mediastinal lymph node metastasis were 51% (95% confidence interval [CI], 47 to 54%) and 85% (95% CI, 84 to 88%), respectively, confirming that CT scanning has limited ability either to rule in or exclude mediastinal metastasis. For PET scanning, the pooled estimates of sensitivity and specificity for identifying mediastinal metastasis were 74% (95% CI, 69 to 79%) and 85% (95% CI, 82 to 88%), respectively. These findings demonstrate that PET scanning is more accurate than CT scanning. If the clinical evaluation in search of metastatic disease is negative, the likelihood of finding metastasis is low.

Conclusions: CT scanning of the chest is useful in providing anatomic detail, but the accuracy of chest CT scanning in differentiating benign from malignant lymph nodes in the mediastinum is poor. PET scanning has much better sensitivity and specificity than chest CT scanning for staging lung cancer in the mediastinum, and distant metastatic disease can be detected by PET scanning. With either test, abnormal findings must be confirmed by tissue biopsy to ensure accurate staging.

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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.

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Journal of Acquired Immune Deficiency Syndrome
Authors
Douglas K. Owens
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Two common means of controlling infectious diseases are screening and contact tracing. Which should be used, and when? We consider the problem of determining the cheapest mix of screening and contact tracing necessary to achieve a desired endemic prevalence of a disease or to identify a specified number of cases. We perform a partial equilibrium analysis of small-scale interventions, assuming that prevalence is unaffected by the intervention; we develop a full equilibrium analysis where we compare the long-term cost of various combinations of screening and contact tracing needed to achieve a given equilibrium prevalence; and we solve the problem of minimizing the total costs of identifying and treating disease cases plus the cost of untreated disease cases. Our analysis provides several insights.

First, contact tracing is only cost effective when prevalence is below a threshold value. This threshold depends on the relative cost per case found by screening versus contact tracing. Second, for a given contact tracing policy, the screening rate needed to achieve a given prevalence or identify a specified number of cases is a decreasing function of disease prevalence. As prevalence increases above the threshold (and contact tracing is discontinued), the screening rate jumps discontinuously to a higher level. Third, these qualitative results hold when we consider unchanged or changed prevalence, and short-term or long-term costs.

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Health Care Management Science
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Margaret L. Brandeau
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Background: As many as 10% of Asian and Pacific Islander adults in the United States are chronically infected with hepatitis B virus (HBV), and up to two thirds are unaware that they are infected. Without proper medical management and antiviral therapy, up to 25% of Asian and Pacific Islander persons with chronic HBV infection will die of liver disease.

Objective: To assess the cost-effectiveness of 4 HBV screening and vaccination programs for Asian and Pacific Islander adults in the United States.

Design: Markov model with costs and benefits discounted at 3%.

Data Source: Published literature and expert opinion. TARGET

Population: Asian and Pacific Islander adults (base-case age, 40 years; sensitivity analysis conducted on ages 20 to 60 years).

Time Horizone: Lifetime.

Perspective: U.S. societal.

Interventions: A universal vaccination strategy in which all individuals are given a 3-dose vaccination series; a screen-and-treat strategy, in which individuals are given blood tests to determine whether they are chronically infected, and infected persons are monitored and treated; a screen, treat, and ring vaccinate strategy, in which all individuals are tested for chronic HBV infection and close contacts of infected persons are screened and vaccinated if needed; and a screen, treat, and vaccinate strategy, in which all individuals are tested and then vaccinated with a 3-dose series if needed. In all cases, persons found to be chronically infected are monitored and treated if indicated.

Outcome Measure: Costs (2006 U.S. dollars), quality-adjusted life-years (QALYs), and incremental cost-effectiveness.

Results of Base-case Analysis: Compared with the status quo, the screen-and-treat strategy has an incremental cost-effectiveness ratio of $36,088 per QALY gained. The screen, treat, and ring vaccinate strategy gains more QALYs than the screen and treat strategy and incurs modest incremental costs, leading to incremental cost-effectiveness of $39,903 per QALY gained compared with the screen and treat strategy. The universal vaccination and screen, treat, and vaccinate strategies were weakly dominated by the other 2 strategies.

Results of Sensitivity Analysis: Over a wide range of variables, the incremental cost-effectiveness ratios of the screen and treat and screen, treat, and ring vaccinate strategies were less than $50,000 per QALY gained.

Limitations: Results depend on the accuracy of the underlying data and assumptions. The long-term effectiveness of new and future HBV treatments is uncertain.

Conclusions: Screening programs for HBV among Asian and Pacific Islander adults are likely to be cost effective. Clinically significant benefits accrue from identifying chronically infected persons for medical management and vaccinating their close contacts. Such efforts can greatly reduce the burden of HBV-associated liver cancer and chronic liver disease in the Asian and Pacific Islander population.

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Annals of Internal Medicine
Authors
Margaret L. Brandeau
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Two common means of controlling infectious diseases are screening and contact tracing. Which should be used, and when? We consider the problem of determining the cheapest mix of screening and contact tracing necessary to achieve a desired endemic prevalence of a disease or to identify a specified number of cases.

We perform a partial equilibrium analysis of small-scale interventions, assuming that prevalence is unaffected by the intervention; we develop a full equilibrium analysis where we compare the long-term cost of various combinations of screening and contact tracing needed to achieve a given equilibrium prevalence; and we solve the problem of minimizing the total costs of identifying and treating disease cases plus the cost of untreated disease cases. Our analysis provides several insights.

First, contact tracing is only cost effective when prevalence is below a threshold value. This threshold depends on the relative cost per case found by screening versus contact tracing. Second, for a given contact tracing policy, the screening rate needed to achieve a given prevalence or identify a specified number of cases is a decreasing function of disease prevalence. As prevalence increases above the threshold (and contact tracing is discontinued), the screening rate jumps discontinuously to a higher level. Third, these qualitative results hold when we consider unchanged or changed prevalence, and short-term or long-term costs.

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Mathematical Biosciences
Authors
Margaret L. Brandeau
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Purpose: One-year adjuvant trastuzumab (AT) therapy, with or without anthracyclines, increases disease-free and overall survival in early-stage HER2/neu-positive breast cancer. We sought to evaluate the cost effectiveness of these regimens, which are expensive and potentially toxic.

Methods: We used a Markov health-state transition model to simulate three adjuvant therapy options for a cohort of 49-year-old women with HER2/neu-positive early-stage breast cancer: conventional chemotherapy without trastuzumab; anthracycline-based AT regimens used in the National Surgical Adjuvant Breast and Bowel Project B-31 and North Central Cancer Treatment Group N9831 trials; and the nonanthracycline AT regimen used in the Breast Cancer International Research group 006 trial. The base case used treatment efficacy measures reported in the randomized clinical trials of AT. We measured health outcomes in quality-adjusted life-years (QALYs) and costs in 2005 United States dollars (US$) and subjected results to probabilistic sensitivity analysis.

Results: In the base case, the anthracycline-based AT arm has an incremental cost-effectiveness ratio (ICER) of $39,982/QALY, whereas the nonanthracycline AT arm is more expensive and less effective; this result is insensitive to changes in recurrence rates, but if there is no benefit after 4 years, ICERs exceed $100,000/QALY for both AT arms. Results are moderately sensitive to variation in breast cancer survival rates and trastuzumab cost, and less sensitive to variations in cardiac toxicity.

Conclusion: AT has an ICER comparable to those for other widely used interventions. Longer clinical follow-up is warranted to evaluate the long-term efficacy and toxicity of different AT regimens.

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Journal of Clinical Oncology
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Objectives: We examined the utility of the Veterans Health Administration (VHA) universal screening program for military sexual violence.

Methods: We analyzed VHA administrative data for 185 880 women and 4139888 men who were veteran outpatients and were treated in VHA health care settings nationwide during 2003.

Results: Screening was completed for 70% of patients. Positive screens were associated with greater odds of virtually all categories of mental health comorbidities, including posttraumatic stress disorder (adjusted odds ratio [AOR]=8.83; 99% confidence interval [CI] = 8.34, 9.35 for women; AOR = 3.00; 99% CI = 2.89, 3.12 for men). Associations with medical comorbidities (e.g., chronic pulmonary disease, liver disease, and for women, weight conditions) were also observed. Significant gender differences emerged.

Conclusions: The VHA policies regarding military sexual trauma represent a uniquely comprehensive health care response to sexual trauma. Results attest to the feasibility of universal screening, which yields clinically significant information with particular relevance to mental health and behavioral health treatment. Women’s health literature regarding sexual trauma will be particularly important to inform health care services for both male and female veterans.

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American Journal of Public Health
Authors
Mark W. Smith
Susan M. Frayne
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Background: The comparative effectiveness of coronary artery bypass graft (CABG) surgery and percutaneous coronary intervention (PCI) for patients in whom both procedures are feasible remains poorly understood.

Purpose: To compare the effectiveness of PCI and CABG in patients for whom coronary revascularization is clinically indicated.

Data Sources: MEDLINE, EMBASE, and Cochrane databases (1966–2006); conference proceedings; and bibliographies of retrieved articles. Study Selection: Randomized, controlled trials (RCTs) reported in any language that compared clinical outcomes of PCI with those of CABG, and selected observational studies.

Data Extraction: Information was extracted on study design, sample characteristics, interventions, and clinical outcomes.

Data Synthesis: The authors identified 23 RCTs in which 5019 patients were randomly assigned to PCI and 4944 patients were randomly assigned to CABG. The difference in survival after PCI or CABG was less than 1% over 10 years of follow-up. Survival did not differ between PCI and CABG for patients with diabetes in the 6 trials that reported on this subgroup. Procedure-related strokes were more common after CABG than after PCI (1.2% vs. 0.6%; risk difference, 0.6%; P = 0.002). Angina relief was greater after CABG than after PCI, with risk differences ranging from 5% to 8% at 1 to 5 years (P < 0.001). The absolute rates of angina relief at 5 years were 79% after PCI and 84% after CABG. Repeated revascularization was more common after PCI than after CABG (risk difference, 24% at 1 year and 33% at 5 years; P < 0.001); the absolute rates at 5 years were 46.1% after balloon angioplasty, 40.1% after PCI with stents, and 9.8% after CABG. In the observational studies, the CABG–PCI hazard ratio for death favored PCI among patients with the least severe disease and CABG among those with the most severe disease.

Limitations: The RCTs were conducted in leading centers in selected patients. The authors could not assess whether comparative outcomes vary according to clinical factors, such as extent of coronary disease, ejection fraction, or previous procedures. Only 1 small trial used drug-eluting stents.

Conclusion: Compared with PCI, CABG was more effective in relieving angina and led to fewer repeated revascularizations but had a higher risk for procedural stroke. Survival to 10 years was similar for both procedures.

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Journal Articles
Publication Date
Journal Publisher
Annals of Internal Medicine
Authors
Douglas K. Owens
Mark A. Hlatky
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