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Biomedical subjects

K A Freedberg

Publications and source records attributed to K A Freedberg.

At least 19 recordsLinked to original sources
PubMed2006

Impact of opportunistic diseases on chronic mortality in HIV-infected adults in Côte d'Ivoire.

OBJECTIVE: To estimate incidence rates of opportunistic diseases (ODs) and mortality for patients with and without a history of OD among HIV-infected patients in Côte d'Ivoire. METHODS: Using incidence density analysis, we estimated rates of ODs and chronic mortality by CD4 count in patients in a cotrimoxazole prophylaxis trial in Abidjan before the highly active antiretroviral therapy (HAART) era. Chronic mortality was defined as death without a history of OD or death more than 30 days after an OD diagnosis. We used Poisson's regression to examine the effect of OD history on chronic mortality after adjusting for age, gender, and current CD4 count. RESULTS: Two hundred and seventy patients (40% male, mean age 33 years, median baseline CD4 count 261 cells/microl) were followed up for a median of 9.5 months. Bacterial infections and tuberculosis were the most common severe ODs. Of 47 patients who died, 9 (19%) died within 30 days of an OD, 26 (55%) died more than 30 days after an OD, and 12 (26%) died with no OD history. The chronic mortality rate was 31.0/100 person-years for those with an OD history, and 11.1/100 person-years for those with no OD history (rate ratio (RR) 2.81, 95% confidence interval (CI): 1.43 - 5.54). Multivariate analysis revealed that OD history remained an independent predictor of mortality (RR 2.15, 95% CI: 1.07 - 4.33) after adjusting for CD4 count, age and gender. CONCLUSIONS: Before the HAART era, a history of OD was associated with increased chronic HIV mortality in Côte d'Ivoire, even after adjusting for CD4 count. These results provide further evidence supporting OD prophylaxis in HIV-infected patients.

AIDS-Related Opportunistic Infections↗
PubMed2002

Prevention of human immunodeficiency virus-related opportunistic infections in France: a cost-effectiveness analysis.

A simulation model of human immunodeficiency virus (HIV) disease, which incorporated French data on the progression of HIV disease in the absence of antiretroviral therapy and on cost, was used to determine the clinical impact and cost-effectiveness of different strategies for the prevention of opportunistic infections in French patients who receive highly active antiretroviral therapy (HAART). Compared with use of no prophylaxis, use of trimethoprim-sulfamethoxazole (TMP-SMZ) increased per-person lifetime costs from euro 185,600 to euro 187,900 and quality-adjusted life expectancy from 112.2 to 113.7 months, for an incremental cost-effectiveness ratio of euro 18,700 per quality-adjusted life-year (euro/QALY) gained. Compared with use of TMP-SMZ alone, use of TMP-SMZ plus azithromycin cost euro 23,900/QALY gained; adding fluconazole cost an additional euro 54,500/QALY gained. All strategies that included oral ganciclovir had cost-effectiveness ratios that exceeded euro 100,000/QALY gained. In the era of HAART, on the basis of French data, prophylaxis against Pneumocystis carinii pneumonia, toxoplasmic encephalitis, and Mycobacterium avium complex bacteremia is cost-effective. Prophylaxis against fungal and cytomegalovirus infections is less cost-effective than are other therapeutic options for HIV disease and should remain of lower priority.

AIDS-Related Opportunistic Infections↗
PubMed2002

Validity and responsiveness of the euroqol as a measure of health-related quality of life in people enrolled in an AIDS clinical trial.

OBJECTIVE: Brief utility measures are needed in clinical trials in addition to existing descriptive measures of health-related quality of life (HRQOL). We examined the reliability and validity of the EuroQol (EQ-SD) and MOS-HIV and their responsiveness to HIV-related clinical events. METHODS: Subjects with advanced HIV disease (CD4 < 100) were enrolled in a randomized trial for CMV prophylaxis (n = 990). The EQ-5D includes a weighted sum of five domains (EQ-5D Index) and a visual analog scale (EQ-VAS). The MOS-HIV has 10 subscales and physical (PHS) and mental health summary scores (MHS). Construct validity of the EQ-5D was tested based on hypothesized relationships to subscales of the MOS-HIV. Relative precision and responsiveness to adverse experiences and opportunistic infections (Ols) were compared for the two instruments. RESULTS: Mean age of the patients was 38, 94% were male, 80% white, and 7% had injected drugs. Mean baseline scores for EQ-5D Index and EQ-VAS were 0.80 and 76.0, respectively, 28 and 4% reported maximum scores. Mean MOS-HIV subscales score ranged from 55 (role) to 84 (cognitive); mean PHS and MHS were 47.4 and 49.5, respectively. Correlations between MOS-HIV subscales and EQ-5D Index ranged from 0.45 (role) to 0.63 (pain); correlations with EQ-VAS ranged from 0.33 (cognitive) to 0.66 (health perceptions). Correlations between MOS-HIV PHS and MHS with EQ-5D Index were 0.61 and 0.58; and with EQ-VAS, 0.57 and 0.60, respectively. Responsiveness to adverse experiences was highest for MOS-HIV pain and PHS (effect sizes = 0.9 and 0.4); pain had the highest relative precision (2.4) for adverse experiences: EQ-VAS had the greatest relative precision (1.6) for developing an OI. CONCLUSION: In these patients with advanced HIV disease. EQ-5D showed good construct validity, but there may be a ceiling effect for its EQ-5D Index component. EQ-5D was less responsive to adverse events than the MOS-HIV. However, the EQ-VAS was most sensitive to developing an OI and is likely to be a useful measure of HRQOL for generating QALYs in cost-utility studies involving patients with advanced HIV disease.

AIDS-Related Opportunistic Infections↗
PubMed2001

Positive Epstein-Barr virus heterophile antibody tests in patients with primary human immunodeficiency virus infection.

PURPOSE: To describe three cases of primary human immunodeficiency virus (HIV) infection in patients who had laboratory studies consistent with infectious mononucleosis. SUBJECTS: We describe 3 patients who presented with a viral syndrome, had a positive heterophile antibody test, and were diagnosed with primary HIV infection. RESULTS: The results of Epstein-Barr virus serology studies in each of these patients were consistent with chronic, but not acute, Epstein-Barr virus infection. HIV antibody tests were negative, and HIV RNA was >500,000 copies/mL in each patient. CONCLUSIONS: Clinicians should recognize that a positive heterophile antibody test in the setting of an acute viral illness does not exclude the diagnosis of primary HIV infection, although reactivation of latent Epstein-Barr virus infection cannot be ruled out. Patients presenting with nonspecific viral syndromes should be assessed for HIV risk behaviors and tested for primary HIV infection when appropriate.

AIDS-Related Opportunistic Infections↗
PubMed2001

Investigation of primary human immunodeficiency virus infection in patients who test positive for heterophile antibody.

In light of a recent report of 3 false-positive results of Epstein-Barr virus heterophile tests caused by HIV infection, we sought to assess the frequency of this occurrence. One hundred thirty-two positive heterophile antibody-tested serum samples were obtained from 2 tertiary care facilities in Boston to assess for HIV, and all tested negative for HIV plasma RNA. This study shows that false-positive results of heterophile tests are not frequently associated with primary HIV infection.

Antibodies, Heterophile↗
PubMed2001

Use of genotypic resistance testing to guide hiv therapy: clinical impact and cost-effectiveness.

BACKGROUND: Genotypic sequencing for drug-resistant strains of HIV can guide the choice of antiretroviral therapy. OBJECTIVE: To assess the cost-effectiveness of genotypic resistance testing for patients acquiring drug resistance through failed treatment (secondary resistance) and those infected with resistant virus (primary resistance). DESIGN: Cost-effectiveness analysis with an HIV simulation model incorporating CD4 cell count and HIV RNA level as predictors of disease progression. DATA SOURCES: Published randomized trials and data from the Multicenter AIDS Cohort Study, the national AIDS Cost and Services Utilization Survey, the Red Book, and an institutional cost-accounting system. TARGET POPULATION: HIV-infected patients in the United States with baseline CD4 counts of 0.250 x 10(9) cells/L. TIME HORIZON: Lifetime. PERSPECTIVE: Societal. INTERVENTIONS: Genotypic resistance testing and clinical judgment, compared with clinical judgment alone, in two contexts: after initial treatment failure (secondary resistance testing) and before initiation of antiretroviral therapy (primary resistance testing). OUTCOME MEASURES: Life expectancy, quality-adjusted life expectancy, and cost-effectiveness in dollars per quality-adjusted life-year (QALY) gained. RESULTS OF BASE-CASE ANALYSIS: Secondary resistance testing increased life expectancy by 3 months, at a cost of $17 900 per QALY gained. The cost-effectiveness of primary resistance testing was $22 300 per QALY gained with a 20% prevalence of primary resistance but increased to $69 000 per QALY gained with 4% prevalence. RESULTS OF SENSITIVITY ANALYSIS: The cost-effectiveness ratio for secondary resistance testing remained under $25 000 per QALY gained, even when effectiveness and cost of testing and antiretroviral therapy, quality-of-life weights, and discount rate were varied. CONCLUSIONS: Genotypic antiretroviral resistance testing following antiretroviral failure is cost-effective. Primary resistance testing also seems to be reasonably cost-effective and will become more so as the prevalence of primary resistance increases.

Anti-HIV Agents↗
PubMed2001

The cost effectiveness of combination antiretroviral therapy for HIV disease.

BACKGROUND: Combination antiretroviral therapy with a combination of three or more drugs has become the standard of care for patients with human immunodeficiency virus (HIV) infection in the United States. We estimated the clinical benefits and cost effectiveness of three-drug antiretroviral regimens. METHODS: We developed a mathematical simulation model of HIV disease, using the CD4 cell count and HIV RNA level as predictors of the progression of disease. Outcome measures included life expectancy, life expectancy adjusted for the quality of life, lifetime direct medical costs, and cost effectiveness in dollars per quality-adjusted year of life gained. Clinical data were derived from major clinical trials, including the AIDS Clinical Trials Group 320 Study. Data on costs were based on the national AIDS Cost and Services Utilization Survey, with drug costs obtained from the Red Book. RESULTS: For patients similar to those in the AIDS Clinical Trials Group 320 Study (mean CD4 cell count, 87 per cubic millimeter), life expectancy adjusted for the quality of life increased from 1.53 to 2.91 years, and per-person lifetime costs increased from $45,460 to $77,300 with three-drug therapy as compared with no therapy. The incremental cost per quality-adjusted year of life gained, as compared with no therapy, was $23,000. On the basis of additional data from other major studies, the cost-effectiveness ratio for three-drug therapy ranged from $13,000 to $23,000 per quality-adjusted year of life gained. The initial CD4 cell count and drug costs were the most important determinants of costs, clinical benefits, and cost effectiveness. CONCLUSIONS: Treatment of HIV infection with a combination of three antiretroviral drugs is a cost-effective use of resources.

AIDS-Related Opportunistic Infections↗
PubMed2001

Preevaluation of clinical trial data: the case of preemptive cytomegalovirus therapy in patients with human immunodeficiency virus.

We developed a mathematical simulation model to anticipate outcomes from an upcoming trial of targeted, preemptive cytomegalovirus (CMV) therapy in high-risk, human immunodeficiency virus (HIV)-infected patients identified by means of CMV polymerase chain reaction screening. We estimated the costs and consequences of CMV prophylaxis in patients with CD4(+) counts < or =100 cells/microL under various assumptions regarding disease progression, complication rates, drug effects, and costs. Without CMV preemptive therapy, lifetime costs average $44,600 with expected duration of survival of 19.16 quality-adjusted life-months and 213 CMV cases per 1000 patients. Targeted preemptive therapy with orally administered valganciclovir increases costs and duration of survival to $46,900 and 19.63 quality-adjusted life-months, respectively. CMV cases decrease to 174 per 1000 patients. The cost per quality-adjusted life-year gained is $59,000. This result compares favorably with other strategies in end-stage HIV disease but hinges on valganciclovir cost and efficacy assumptions and the absence of minimally effective salvage antiretroviral therapy for HIV. The upcoming trial should resolve the clinical uncertainty surrounding some of these assumptions.

AIDS-Related Opportunistic Infections↗
PubMed2001

Understanding delay to medical care for HIV infection: the long-term non-presenter.

OBJECTIVE: To examine delayed presentation for HIV testing and primary care in the second decade of the AIDS epidemic. DESIGN: Cohort study in two urban hospitals in the USA between February 1994 and April 1996. METHODS: A total of 203 consecutive outpatients on initial HIV primary care presentation were interviewed about sociodemographic characteristics, alcohol and drug use, social support, sexual practices, HIV testing, awareness of possible HIV infection, and CD4 cell count. MAIN OUTCOME MEASURE: Duration of delay to medical presentation in years based on CD4 cell count, factors independently associated with low CD4 cell counts, frequency of awareness of HIV risk before testing. RESULTS: The estimated mean duration between acquiring HIV infection and initial presentation to primary care was 8.1 years (95% CI 7.5, 8.6) based on our cohort's median initial CD4 cell count of 280/microl. Male sex, older age, and no jail time were associated with lower CD4 cell counts; 34% reported not being aware that they were at risk of HIV before testing. Heterosexual intercourse as a risk behavior for HIV was the most statistically significant factor for personal unawareness of HIV risk. Of those who acknowledged awareness, the mean time between awareness of HIV risk and testing was 2.5 years (median 1.0 year). CONCLUSION: In the pre-highly active antiretroviral therapy era, HIV-infected patients frequently initiated primary medical care years after initial infection, at a time of advanced immunosuppression. Over one-third of HIV-infected patients were not cognisant of their HIV risk before testing, a condition significantly associated with heterosexual intercourse as the only HIV risk behavior.

Adult↗
PubMed2001

Cost effectiveness of human papillomavirus testing to augment cervical cancer screening in women infected with the human immunodeficiency virus.

PURPOSE: To determine the cost effectiveness of incorporating molecular testing for high-risk types of human papillomavirus into a cervical cancer screening program for women infected with the human immunodeficiency virus (HIV). SUBJECTS AND METHODS: We developed a Markov model to simulate the natural history of cervical cancer precursor lesions in HIV-infected women. Probabilities of progression and regression of cervical lesions were conditional on transient or persistent infection with human papillomavirus, as well as stage of HIV and effectiveness of antiretroviral therapy. Incorporating data from prospective cohort studies, national databases, and published literature, the model was used to calculate quality-adjusted life expectancy, life expectancy, lifetime costs, and incremental cost-effectiveness ratios for two main strategies: targeted screening-human papillomavirus testing is added to the initial two cervical cytology smears obtained after an HIV diagnosis and subsequent screening intervals are modified based on the test results; and universal screening-no testing for human papillomavirus is performed, and a single cytology screening interval is applied to all women. RESULTS: In HIV-infected women on anti-retroviral therapy, a targeted screening strategy in which cervical cytology screening was conducted every 6 months for women with detected human papillomavirus DNA, and annually for all others, cost $10,000 to $14,000 per quality-adjusted life year gained compared with no screening. A universal screening strategy consisting of annual cervical cytology for all women was 15% less effective and had a less attractive cost-effectiveness ratio. Targeted screening remained economically attractive in multiple sensitivity analyses, although when the overall incidence of cervical cancer precursor lesions was lowered by 75%, the screening interval for women with detected human papillomavirus DNA could be widened to 1 year. CONCLUSIONS: Adding human papillomavirus testing to the two cervical cytology smears obtained in the year after an HIV diagnosis, and modifying subsequent cytology screening intervals based on the results, appears to be an effective and cost-effective modification to current recommendations for annual cytology screening in HIV-infected women.

AIDS-Related Opportunistic Infections↗
PubMed2001

Cost-effectiveness of prenatal screening for postpartum thyroiditis.

Five percent of all pregnant women and 25% of pregnant women with insulin-dependent diabetes mellitus (IDDM) develop postpartum thyroiditis (PPT) during the first year after delivery. PPT has significant morbidity and can be predicted prenatally by the presence of thyroid peroxidase (TPO) antibody. Our objective was to estimate the cost-effectiveness of screening pregnant women for the TPO antibody versus the current strategy of no screening test or an alternative strategy of a thyroid-stimulating hormone (TSH) test 6 weeks postpartum. We performed cost-effectiveness analysis using a decision tree model that accounted for cases of PPT detected, medical outcomes of screening, and costs of screening and care. Hypothetical cohorts of 1000 pregnant women with uncomplicated pregnancies and 1000 pregnant women with IDDM were used to determine direct medical costs, quality-adjusted life years, and cases of PPT detected. The cost of testing 1000 pregnant women for TSH at the 6 week postpartum visit was $75,000, with an effectiveness of 995.2 quality-adjusted life years resulting in a cost-effectiveness ratio of $48,000 per quality-adjusted life year. Checking a TPO antibody was more effective (995.5 quality-adjusted life years) but also more expensive ($93,000). The incremental cost-effectiveness ratio of the TPO antibody strategy was $60,000 per quality-adjusted life year. Results were most sensitive to changes in the test characteristics, incidence of disease, and percentage of women with PPT who were symptomatic. A separate analysis for women with IDDM resulted in an incremental cost-effectiveness ratio of $13,000 per quality-adjusted life year for the TSH strategy and $32,000 per quality-adjusted life year for the TPO strategy. Screening for PPT is likely to be reasonably cost-effective and should be considered for inclusion as part of routine pregnancy care.

Adult↗
PubMed2001

Incidence of primary opportunistic infections in two human immunodeficiency virus-infected French clinical cohorts.

BACKGROUND: Clinical guidelines for the prevention of opportunistic infections in human immunodeficiency virus (HIV)-infected individuals have been developed on the basis of natural history data collected in the USA. The objective of this study was to estimate the incidence of primary opportunistic infections in HIV-infected individuals in geographically distinct cohorts in France. METHODS: We conducted our study on 2664 HIV-infected patients from the Tourcoing AIDS Reference Centre and the hospital-based information system of the Groupe d'Epidémiologie Clinique du SIDA en Aquitaine enrolled from January 1987 to September 1995 and followed through December 1995. We estimated: (1) CD4-adjusted incidence rates of seven primary opportunistic infections in the absence of prophylaxis for that specific infection or any antiretroviral drugs other than zidovudine; and (2) CD4 lymphocyte count decline. RESULTS: The highest incidence rates for all opportunistic infections studied occurred in patients with CD4 counts < 200/microl. With CD4 counts < 50/microl, the most common opportunistic infections were toxoplasmic encephalitis (12.6 per 100 person-years) and Pneumocystis carinii pneumonia (11.4 per 100 person-years). Mycobacterium tuberculosis was the least common opportunistic infection (< 5.0/100 person-years). Even with CD4 counts > 300/microl, cases of Pneumocystis carinii pneumonia and toxoplasmic encephalitis were reported. The mean CD4 lymphocyte decline per month was 4.6 cells/microl. There was a significant association between HIV risk behaviour and the incidence of cytomegalovirus infection, between calendar year and the incidence of Pneumocystis carinii pneumonia, toxoplasmic encephalitis and Candida esophagitis, and between geographical area and the incidence of Pneumocystis carinii pneumonia and cytomegalovirus infection. CONCLUSIONS: Geographical differences exist in the incidence of HIV-related opportunistic infections. These results can be used to define local priorities for prophylaxis of opportunistic infections.

AIDS-Related Opportunistic Infections↗
PubMed2001

Cost-effectiveness of earlier initiation of antiretroviral therapy for uninsured HIV-infected adults.

OBJECTIVES: This study was designed to examine the societal cost-effectiveness and the impact on government payers of earlier initiation of antiretroviral therapy for uninsured HIV-infected adults. METHODS: A state-transition simulation model of HIV disease was used. Data were derived from the Multicenter AIDS Cohort Study, published randomized trials, and medical care cost estimates for all government payers and for Massachusetts, NewYork, and Florida. RESULTS: Quality-adjusted life expectancy increased from 7.64 years with therapy initiated at 200 CD4 cells/microL to 8.21 years with therapy initiated at 500 CD4 cells/microL. Initiating therapy at 500 CD4/microL was a more efficient use of resources than initiating therapy at 200 CD4/microL and had an incremental cost-effectiveness ratio of $17,300 per quality-adjusted life-year gained, compared with no therapy. Costs to state payers in the first 5 years ranged from $5,500 to $24,900 because of differences among the states in the availability of federal funds forAIDS drug assistance programs. CONCLUSIONS: Antiretroviral therapy initiated at 500 CD4 cells/microL is cost-effective from a societal: perspective compared with therapy initiated later. States should consider Medicaid waivers to expand access to early therapy.

Anti-HIV Agents↗
PubMed2000

Cost-effectiveness of screening for anal squamous intraepithelial lesions and anal cancer in human immunodeficiency virus-negative homosexual and bisexual men.

PURPOSE: Homosexual and bisexual men are at an increased risk for human papillomavirus-induced squamous intraepithelial lesions and cancer of the anus. Our objective was to estimate the cost-effectiveness of screening for anal squamous intraepithelial lesions in these high-risk patients. SUBJECTS AND METHODS: A Markov model was developed to evaluate alternative screening strategies using anal cytology in a hypothetical cohort of homosexual and bisexual men. Data were obtained from prospective cohort studies, national databases, Medicare reimbursement rates, and the published literature. Model outcomes included life expectancy, quality-adjusted life expectancy, total lifetime costs, and incremental cost-effectiveness ratios. RESULTS: The undiscounted life expectancy gain associated with anal cytology screening every 3 years was 5.5 months. Compared with no screening, screening every 3 years increased the discounted quality-adjusted life expectancy by 1.8 months and cost $7,000 per quality-adjusted life year (QALY) gained. Screening every 2 years cost $15,100 per QALY gained compared with screening every 3 years. Annual screening provided incremental benefits of less than 0.5 quality-adjusted months and had an incremental cost of $34,800 per QALY gained. Screening every 6 months provided little additional benefit (i.e, 5 days) over that of annual screening and had an incremental cost of $143,500 per QALY gained. CONCLUSION: In homosexual and bisexual men, screening every 2 or 3 years for anal squamous intraepithelial lesions with anal cytology would provide life-expectancy benefits comparable with other accepted preventive health measures, and would be cost-effective.

Adult↗
PubMed2000

Performance measures for guidelines on preventing opportunistic infections in patients infected with human immunodeficiency virus.

This article serves as a complement to the 1999 US Public Health Service/Infectious Diseases Society of America guidelines on the prevention of opportunistic infections in persons infected with HIV, published in this issue of Clinical Infectious Diseases [1]. A number of performance measures to assess compliance with the guidelines and to aid in their implementation are proposed.

AIDS-Related Opportunistic Infections↗