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A David Paltiel

Publications and source records attributed to A David Paltiel.

32 records · Page 2Linked to original sources
PubMed2003

Age does not limit quality of life improvement in cardiac valve surgery.

OBJECTIVES: We sought to determine the association of age with the change in quality of life (QOL) after valve surgery. BACKGROUND: Improvement in QOL is one of the principal goals of valve surgery. These procedures are being done with increasing frequency for older patients. METHODS: We prospectively studied 148 patients with aortic valve procedures and 72 patients with mitral valve procedures. Patients' QOL was measured at baseline and at 18 months using the Medical Outcomes Trust Short Form 36-Item (SF-36) Health Survey (response rate 90%). The association of age with change in QOL was measured by multiple regression analysis and based on two meta-scores of the SF-36: the Mental Component Summary (MCS) and the Physical Component Summary (PCS). RESULTS: Overall improvement in most domains of the SF-36, including the MCS and the PCS scores, was substantial. Improvement in the MCS score was not influenced by age in either aortic (0.09 score point improvement per 10-year age increments; p = 0.9) or mitral (0.90 score point improvement per 10-year age increments; p = 0.3) patients. Similarly, improvement in the PCS score did not vary by age in aortic patients (-1.00 score points per 10-year age increments; p = 0.2) and only slightly varied by age in mitral patients (-1.90 score points per 10-year age increments, p = 0.02). In the latter, despite statistical significance, the association was not substantial or clinically important. CONCLUSIONS: Among patients referred for cardiac valve surgery, age does not appear to limit the QOL benefits of surgery.

Aged↗
PubMed2002

Treatment for primary HIV infection: projecting outcomes of immediate, interrupted, or delayed therapy.

With limited data available on the optimal treatment of primary HIV infection, disease modeling can be used to project clinical outcomes and inform decision makers. The authors developed a simulation model to evaluate the clinical outcomes and life expectancy projections for three primary HIV infection treatment strategies: 1) continuous antiretroviral therapy (ART) initiated at CD4 count <350 cells/mm(3); 2) continuous ART initiated immediately on diagnosis of primary HIV infection; and 3) ART initiated on diagnosis followed by structured treatment interruption. Projected life expectancies for the three strategies were 23.92, 24.46, and 26.07 years, respectively. The impact of key variables was assessed in sensitivity analysis, with the structured treatment interruption strategy remaining the most effective over a broad range of inputs. The immunologic benefit associated with immediate therapy and the potential for antiretroviral resistance due to structured treatment interruption have the most important impact on the optimal strategy. Based on current data, immediate treatment on diagnosis of primary HIV infection followed by structured treatment interruption will likely yield the best outcome. These results can assist decision makers and those planning clinical trials in defining evidence-based performance measures for primary HIV infection treatment and future trials.

Anti-HIV Agents↗
PubMed2002

AIDS Drug Assistance Programs: highlighting inequities in human immunodeficiency virus-infection health care in the United States.

The AIDS Drug Assistance Programs (ADAPs) were founded in 1987 to pay for human immunodeficiency virus (HIV)-related medications in the United States and to help provide prescriptions for HIV-infected patients ineligible for Medicaid who have no private health insurance. As HIV care has shifted from the inpatient to the outpatient arena and as patients live longer because of more-effective antiretroviral therapy, medication costs have increased, and ADAPs have increasingly been operating under emergency measures, with coverage limitations and eligibility restrictions. Because these programs operate at the state level, inequalities in resource distribution to those in need are manifest and appear to contribute to differences in disease outcomes that are based solely on patients' place of residence. Cost-effectiveness analysis would offer a more informed basis for distribution of ADAP resources in an efficient and equitable manner, leading to a standardized national structure.

Acquired Immunodeficiency Syndrome↗
PubMed2002

The relationship of preventable opportunistic infections, HIV-1 RNA, and CD4 Cell counts to chronic mortality.

BACKGROUND: Both HIV-1 RNA and absolute CD4 cell counts have been identified as important predictors of HIV-1 disease progression and mortality. The independent impact of opportunistic infections on the risk of chronic mortality, defined as death beyond 30 days of an opportunistic infection, has not been studied when controlling for HIV-1 RNA. Our objective was to determine the relationship between a history of any of five preventable opportunistic infections (Pneumocystis carinii pneumonia, Mycobacterium avium complex, toxoplasmosis, cytomegalovirus, and candida esophagitis) and chronic mortality. METHODS: Using the Multicenter AIDS Cohort Study (MACS) public use data set of 2193 HIV-infected men in four U.S. cities, we employed a Cox regression model to estimate the impact of a history of preventable opportunistic infection on chronic mortality while controlling for maximum HIV-1 RNA, CD4 cell count, use of antiretroviral drugs, and age. FINDINGS: The chronic mortality rate among individuals with a history of preventable opportunistic infection was 66.7 per 100 person-years compared with 2.3 per 100 person-years for those without a history of preventable opportunistic infection (RR = 28.4, 95% CI: 24.7-32.8). In the adjusted analysis, the relative hazard of death for those with a history of preventable opportunistic infections was 7.0 (5.8-8.3), whereas antiretroviral therapy was associated with a decreased risk of death (0.37 [0.30-0.44]). We found no association between maximum HIV-1 RNA and chronic mortality. There was statistically significant effect modification between preventable opportunistic infections and CD4 cell count (p <.0001). INTERPRETATION: Preventable opportunistic infections cause not only short-term mortality in HIV-1 disease but appear to have a major impact on chronic mortality.

AIDS-Related Opportunistic Infections↗
PubMed2002

Prophylaxis for human immunodeficiency virus-related Pneumocystis carinii pneumonia: using simulation modeling to inform clinical guidelines.

BACKGROUND: Human immunodeficiency virus (HIV)-infected patients receiving highly active antiretroviral therapy (HAART) have experienced a dramatic decrease in Pneumocystis carinii pneumonia (PCP), necessitating reassessment of clinical guidelines for prophylaxis. METHODS: A simulation model of HIV infection was used to estimate the lifetime costs and quality-adjusted life expectancy (QALE) for alternative CD4 cell count criteria for stopping primary PCP prophylaxis in patients with CD4 cell count increases receiving HAART and alternative agents for second-line PCP prophylaxis in those intolerant of trimethoprim-sulfamethoxazole (TMP/SMX). The target population was a cohort of HIV-infected patients in the United States with initial CD4 cell counts of 350/microL who began PCP prophylaxis after their first measured CD4 lymphocyte count less than 200/microL. Data were from randomized controlled trials and other published literature. RESULTS: For patients with CD4 cell count increases during HAART, waiting to stop prophylaxis until the first observed CD4 cell count was greater than 300/microL prevented 9 additional cases per 1000 patients and cost $9400 per quality-adjusted life year (QALY) gained compared with stopping prophylaxis at 200/microL. For patients intolerant of TMP/SMX, using dapsone increased QALE by 2.7 months and cost $4500 per QALY compared with no prophylaxis. Using atovaquone rather than dapsone provided only 3 days of additional QALE and cost more than $1.5 million per QALY. CONCLUSIONS: Delaying discontinuation of PCP prophylaxis until the first observed CD4 cell count greater than 300/microL is cost-effective and provides an explicit "PCP prophylaxis stopping criterion." In TMP/SMX-intolerant patients, dapsone is more cost-effective than atovaquone.

AIDS-Related Opportunistic Infections↗
PubMed2002

The cost-effectiveness of treatment for varicocele related infertility.

PURPOSE: We compared the cost-effectiveness of 4 treatment strategies for varicocele related infertility from the perspective of the health care payor and patient. MATERIALS AND METHODS: Cost-effectiveness analysis was performed by studying 4 treatment strategies, namely observation, surgical varicocelectomy followed by in vitro fertilization (IVF) if unsuccessful, gonadotropin stimulated intrauterine insemination (IUI) followed by IVF if unsuccessful, and immediate IVF. The main outcome measure was incremental cost per live delivery of any number of newborns. RESULTS: Immediate IVF cost more per live delivery and was less effective than varicocelectomy/IVF or IUI/IVF. When electing the latter 2 procedures, the preferred approach depended on the choice of perspective. From the health care payor viewpoint each additional birth that resulted from choosing varicocelectomy/IVF over observation cost $52,152, while each additional birth that occurred by electing IUI/IVF over varicocelectomy/IVF cost $561,423. From the patient perspective, while varicocelectomy/IVF resulted in improved outcomes over observation, a rational decision maker would always be willing to pay the slightly higher cost of IUI/IVF (incremental cost per live birth versus observation $27,371) for the added benefit in effectiveness if they were initially willing to invest in varicocelectomy/IVF (incremental cost per live birth versus observation $27,618). CONCLUSIONS: The optimal choice of treatment for varicocele related infertility depends strongly on the decision maker perspective. Regardless of perspective the most technologically advanced treatment, that is immediate IVF, is never favored. The findings of this study should be used to counsel infertile patients with varicocele that immediate IVF is not cost-effective.

Adult↗
PubMed2002

A novel approach to defining the relationship between lung function and symptom status in asthma.

We present a novel approach to estimating functional relationships between forced expiratory volume in 1 second (FEV(1)) and asthma-related symptoms on a population-wide basis. We used asthma-related clinical trials that reported estimates of mean lung function (measured as FEV(1) percent predicted) and symptoms (symptom score or percentage of symptom days or nighttime awakenings). Using average baseline values from each study in weighted linear regression analyses, we found a negative association between lung function and symptom score (P < 0.001) and the percentage of nighttime awakenings (P = 0.18), but no association between lung function and symptom days. We also found consistent relationships between the mean changes in lung function and symptoms at follow-up within the studies. Functional relationships between FEV(1) percent predicted and asthma-related symptoms can be useful for inferring the effect on the symptoms of a population associated with overall improvements in lung function.

Adult↗
PubMed2002

State AIDS Drug Assistance Programs: equity and efficiency in an era of rapidly changing treatment standards.

BACKGROUND: The 54 state AIDS Drug Assistance Programs (ADAP) provide medications to HIV-infected persons with limited resources. Eligibility and coverage vary, raising concerns about health inequities. OBJECTIVE: To compare the relative clinical and economic performance of ADAP programs. RESEARCH DESIGN: A state-transition simulation model of HIV disease was used to explore the clinical consequences and lifetime costs associated with selected state policies. Clinical data came from the Multicenter AIDS Cohort Study, AIDS Clinical Trials Group Protocol 320, and other published randomized trials. Cost data came from the national AIDS Cost and Services Utilization Survey, and the 1999 Red Book. ADAP data came from National Association of State and Territorial AIDS Directors reports and interviews. MEASURES: Projected life expectancy, quality-adjusted life expectancy, total lifetime direct medical costs, cost-effectiveness in dollars per quality-adjusted life year (QALY) gained. RESULTS: ADAPs vary considerably in terms of formulary policies, health outcomes, expected costs, and cost-efficiency. Conservative projections, based on a cohort with starting mean CD4 count of 250 cells/microL, yield life expectancies ranging from 5.36 to 6.81 life years (4.69-6.01 quality-adjusted life years [QALYs]). Total per person lifetime direct medical costs range from $81,200 to $112,700; higher costs reflect increased spending on medications. Expected costs per QALY gained range from $7000 to $28,000. Under pessimistic assumptions regarding initial CD4 counts, drug efficacy, and discounting, the most comprehensive policy remains below $33,000/QALY. CONCLUSIONS: Even the most comprehensive ADAPs constitute a cost-effective use of HIV care resources. A uniform, national ADAP formulary warrants consideration.

Acquired Immunodeficiency Syndrome↗
PubMed2002

Impact of site of care, race, and Hispanic ethnicity on medication use for childhood asthma.

OBJECTIVE: To understand the importance of source of care and other factors that influence differences in asthma medication use by race and Hispanic ethnicity. METHODS: The Childhood Asthma Severity Study provided 12-month, retrospective, parent-reported questionnaire data on a monthly basis for children ages </=12 years in a community sample of 1002 children and their families from Connecticut and Massachusetts. Medications considered included cromolyn, beta2-agonist, inhaled steroids, anticholinergics, theophylline, and systemic steroids. Information was available on demographics, insurance status, symptom severity, primary care contact, and provider practice types. RESULTS: Black and Hispanic children received fewer beta2-agonists, and Hispanic children received fewer inhaled steroids than white children after adjusting for patients' race, age, gender, insurance status, symptom severity, number of primary care visits for asthma, number of urgent visits to the regular provider, family income, maternal education, and site of care. When multivariate analyses were restricted to patients in private practice, the significant association between Hispanic ethnicity and low inhaled steroid use persisted, whereas differences in beta2-agonist use by race and ethnicity changed little but became nonsignificant. CONCLUSION: Even within private practices, patients' race and ethnicity are associated with clinician nonadherence to national guidelines. Programs to eliminate these disparities will need both to focus on site of care and to intervene at the provider and patient levels to be successful.

Black or African American↗
PubMed2002

Lifetime cost of HIV care in France during the era of highly active antiretroviral therapy.

OBJECTIVE: To estimate the treatment and health care costs of HIV infection or AIDS in France during the era of highly active antiretroviral therapy (HAART). DESIGN: We used a clinical database of HIV-infected patients to calculate the resource use and cost of care for different stages of HIV infection. Costs were incorporated into a computer-based, probabilistic simulation model of the natural history and treatment of HIV infection to estimate the lifetime cost of treating patients with HIV disease. SETTING: A northern France HIV clinical cohort. PARTICIPANTS: 1232 HIV-infected patients followed from January 1994 through July 1998. RESULTS: In the absence of an AIDS-defining event, the average total cost of care ranged from 670 euros (1 euro=US $1.19) per person-month in the highest CD4 stratum (>500/microl) to 1060 euros per person-month in the lowest CD4 stratum (< or = 50/microl). The mean cost of care was estimated at 3370 euros per person-month during the initial months around the occurrence of an AIDS-defining event; at 1750 euros per person-month during the period spanning from 2 months after the diagnosis of specific AIDS-defining event to 1 month prior to death; and at 13010 euros per person-month in the final month prior to death. If clinical management of HIV infection began at a CD4 cell count of 378/microl, as in this cohort, the discounted lifetime cost of treating an HIV-infected French patient was estimated at 214000 euros. The undiscounted costs were 309000 euros over a projected life expectancy of 16.4 years. CONCLUSION: The cost of HIV disease varies widely depending upon the stage of illness. These estimates of stage-specific and lifetime costs of HIV care will assist health policy planners in assessing the burden of disease in the era of HAART and projecting future resource requirements.

Adult↗
PubMedDate not supplied

Economic costs of influenza-related work absenteeism.

BACKGROUND: Influenza vaccinations are currently advocated only for individuals over age 50. However, vaccination of all working-age people may be warranted based on reduced absenteeism from work. OBJECTIVE: This study aims to quantify the association between lost workdays and influenza, controlling for other factors. A secondary aim of the study is to assess the net benefit of expanded vaccination in a workplace setting. RESEARCH DESIGN: Multivariate regression analyses of the 1996 Medical Expenditure Panel Survey Household Component are used to estimate the number of workdays missed because of influenza-like illness (ILI) when controlling for other health, demographic, and employment factors. Mean productivity costs are measured in terms of absences from work and valued in dollar terms. The net benefit of influenza vaccination is estimated using a simple decision analysis. SUBJECTS AND MEASURES: Health, demographic, and employment data for employed individuals between the ages of 22 and 64 years are analyzed. RESULTS: The average number of workdays missed due to ILI was 1.30 days, and the average work loss was valued at 137 US dollars per person. The vaccine strategy was not preferred in the baseline analysis; however, this result was sensitive to assumptions regarding the incidence of influenza, the cost of delivering the vaccine, and the productivity impact of worker absenteeism. Moreover, nonproductivity benefits of vaccination were omitted. CONCLUSIONS: The economic attractiveness of expanded investment in influenza vaccination hinges on employer- and population-specific assumptions. Our analysis provides a simple framework within which competing considerations of disease epidemiology, worker productivity, and economic cost may be weighed.

Absenteeism↗
PubMedDate not supplied

Optimal allocation of testing dollars: the example of HIV counseling, testing, and referral.

BACKGROUND: Health screening programs can be represented as a pathway of sequential processes: offering a test, obtaining consent, conducting the test, providing results, and linking to appropriate care. Using the example of HIV testing, the authors explore the optimal targeting of funds within this pathway. METHODS: The authors develop a microsimulation of HIV testing services and decompose the likelihood that an unidentified HIV-infected person will receive care into the probability of testing [P(test)] and the probability of follow-up [P(follow)] defined as returning for results and linking to care. The authors examine the clinical impact and cost-effectiveness of alternative investments in these component probabilities. RESULTS: At 1% undiagnosed HIV prevalence, cost-effectiveness ratios for HIV testing cluster around $33,000/QALY (quality-adjusted life year) gained. A program with a yield of 0.16 via P(test)=0.20 and P(follow)=0.80 has a cost-effectiveness ratio of $32,900/QALY compared with $36,300/QALY for a program where P(test)=0.80 and P(follow)=0.20. Interventions that improve the probability of success in later stages in the testing pathway [P(follow)] are more cost-effective than investments devoted to earlier stages [P(test)]. CONCLUSIONS: Equivalent pathway outcomes in a screening program do not confer equal value. Limited screening resources are best targeted toward returning for results and linkage among those already identified with disease rather than offering testing to additional people.

AIDS Serodiagnosis↗
PubMedDate not supplied

Fact, fiction, and fairness: resource allocation under the Ryan White CARE Act.

Debate over the reauthorization of the Ryan White CARE Act (RWCA) raises questions of fairness, equity, and efficiency. Critics charge that the program targets disproportionate resources to historical urban epicenters at the expense of underserved areas of incident HIV infection. We used 1998-2004 data on RWCA allocations to examine these claims. We found that states' concentration of AIDS cases within urban areas remains the dominant predictor of RWCA funding, although the impact of concentration declined after 2000. Other state characteristics, such as poverty rates or racial/ethnic diversity, play a much smaller role.

Geography↗