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1.
Nature ; 621(7979): 568-576, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37704722

RESUMO

Growth faltering in children (low length for age or low weight for length) during the first 1,000 days of life (from conception to 2 years of age) influences short-term and long-term health and survival1,2. Interventions such as nutritional supplementation during pregnancy and the postnatal period could help prevent growth faltering, but programmatic action has been insufficient to eliminate the high burden of stunting and wasting in low- and middle-income countries. Identification of age windows and population subgroups on which to focus will benefit future preventive efforts. Here we use a population intervention effects analysis of 33 longitudinal cohorts (83,671 children, 662,763 measurements) and 30 separate exposures to show that improving maternal anthropometry and child condition at birth accounted for population increases in length-for-age z-scores of up to 0.40 and weight-for-length z-scores of up to 0.15 by 24 months of age. Boys had consistently higher risk of all forms of growth faltering than girls. Early postnatal growth faltering predisposed children to subsequent and persistent growth faltering. Children with multiple growth deficits exhibited higher mortality rates from birth to 2 years of age than children without growth deficits (hazard ratios 1.9 to 8.7). The importance of prenatal causes and severe consequences for children who experienced early growth faltering support a focus on pre-conception and pregnancy as a key opportunity for new preventive interventions.


Assuntos
Caquexia , Países em Desenvolvimento , Transtornos do Crescimento , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Gravidez , Caquexia/economia , Caquexia/epidemiologia , Caquexia/etiologia , Caquexia/prevenção & controle , Estudos de Coortes , Países em Desenvolvimento/economia , Países em Desenvolvimento/estatística & dados numéricos , Suplementos Nutricionais , Transtornos do Crescimento/epidemiologia , Transtornos do Crescimento/prevenção & controle , Estudos Longitudinais , Mães , Fatores Sexuais , Desnutrição/economia , Desnutrição/epidemiologia , Desnutrição/etiologia , Desnutrição/prevenção & controle , Antropometria
2.
Artigo em Inglês | MEDLINE | ID: mdl-38476310

RESUMO

We frame the meta-learning of prediction procedures as a search for an optimal strategy in a two-player game. In this game, Nature selects a prior over distributions that generate labeled data consisting of features and an associated outcome, and the Predictor observes data sampled from a distribution drawn from this prior. The Predictor's objective is to learn a function that maps from a new feature to an estimate of the associated outcome. We establish that, under reasonable conditions, the Predictor has an optimal strategy that is equivariant to shifts and rescalings of the outcome and is invariant to permutations of the observations and to shifts, rescalings, and permutations of the features. We introduce a neural network architecture that satisfies these properties. The proposed strategy performs favorably compared to standard practice in both parametric and nonparametric experiments.

3.
JAMA Netw Open ; 3(10): e2017109, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-33090223

RESUMO

Importance: Prediction models are widely used in health care as a way of risk stratifying populations for targeted intervention. Most risk stratification has been done using a small number of predictors from insurance claims. However, the utility of diverse nonclinical predictors, such as neighborhood socioeconomic contexts, remains unknown. Objective: To assess the value of using neighborhood socioeconomic predictors in the context of 1-year risk prediction for mortality and 6 different health care use outcomes in a large integrated care system. Design, Setting, and Participants: Diagnostic study using data from all adults age 18 years or older who had Kaiser Foundation Health Plan membership and/or use in the Kaiser Permantente Northern California: a multisite, integrated health care delivery system between January 1, 2013, and June 30, 2014. Data were recorded before the index date for each patient to predict their use and mortality in a 1-year post period using a test-train split for model training and evaluation. Analyses were conducted in fall of 2019. Main Outcomes and Measures: One-year encounter counts (doctor office, virtual, emergency department, elective hospitalizations, and nonelective), total costs, and mortality. Results: A total of 2 951 588 patients met inclusion criteria (mean [SD] age, 47.2 [17.4] years; 47.8% were female). The mean (SD) Neighborhood Deprivation Index was -0.32 (0.84). The areas under the receiver operator curve ranged from 0.71 for emergency department use (using the LASSO method and electronic health record predictors) to 0.94 for mortality (using the random forest method and electronic health record predictors). Neighborhood socioeconomic status predictors did not meaningfully increase the predictive performance of the models for any outcome. Conclusions and Relevance: In this study, neighborhood socioeconomic predictors did not improve risk estimates compared with what is obtainable using standard claims data regardless of model used.


Assuntos
Registros Eletrônicos de Saúde/estatística & dados numéricos , Mortalidade , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Características de Residência/estatística & dados numéricos , Classe Social , Adulto , California , Estudos de Coortes , Feminino , Previsões , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais
4.
Int J Epidemiol ; 47(5): 1432-1442, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-29982496

RESUMO

Background: Migration may impact the mental health of family members who remain in places of origin. We examined longitudinal associations between having an adult child migrant and mental health, for middle-aged and older Mexican adults accounting for complex time-varying confounding. Methods: Mexican Health and Aging Study cohort (N = 11 806) respondents ≥50 years completed a 9-item past-week depressive symptoms scale; scores of ≥5 reflected elevated depressive symptoms. Expected risk differences (RD) for elevated depressive symptoms at each wave due to having at least one (versus no) adult child migrant in the US or in another Mexican city were estimated with longitudinal targeted maximum likelihood estimation. Results: Women with at least one adult child in the US had a higher adjusted baseline prevalence of elevated depressive symptoms (RD: 0.063, 95% CI: 0.035, 0.091) compared to women with no adult children in the US. Men with at least one child in another Mexican city at all three study waves had a lower adjusted prevalence of elevated depressive symptoms at 11-year follow-up (RD: -0.042, 95% CI: -0.082, -0.003) compared to those with no internal migrant children over those waves. For men and women with ≤3 total children, adverse associations between having an adult child in the US and depressive symptoms persisted beyond baseline. Conclusions: Associations between having an adult child migrant and depressive symptoms varied by respondent gender, family size, and the location of the child migrant. Trends in population aging and migration bring new urgency to examining associations with other outcomes and in other settings.


Assuntos
Envelhecimento/psicologia , Depressão/epidemiologia , Pais/psicologia , Migrantes/estatística & dados numéricos , Idoso , Características da Família , Feminino , Humanos , Estudos Longitudinais , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Análise de Regressão , Fatores de Risco , Fatores Socioeconômicos
5.
Artigo em Inglês | MEDLINE | ID: mdl-28559746

RESUMO

BACKGROUND: Ofatumumab (Arzerra®, Novartis) is a treatment for chronic lymphocytic leukemia refractory to fludarabine and alemtuzumab [double refractory (DR-CLL)]. Ofatumumab was licensed on the basis of an uncontrolled Phase II study, Hx-CD20-406, in which patients receiving ofatumumab survived for a median of 13.9 months. However, the lack of an internal control arm presents an obstacle for the estimation of comparative effectiveness. METHODS: The objective of the study was to present a method to estimate the cost effectiveness of ofatumumab in the treatment of DR-CLL. As no suitable historical control was available for modelling, the outcomes from non-responders to ofatumumab were used to model the effect of best supportive care (BSC). This was done via a Cox regression to control for differences in baseline characteristics between groups. This analysis was included in a partitioned survival model built in Microsoft® Excel with utilities and costs taken from published sources, with costs and quality-adjusted life years (QALYs) were discounted at a rate of 3.5% per annum. RESULTS: Using the outcomes seen in non-responders, ofatumumab is expected to add approximately 0.62 life years (1.50 vs. 0.88). Using published utility values this translates to an additional 0.30 QALYs (0.77 vs. 0.47). At the list price, ofatumumab had a cost per QALY of £130,563, and a cost per life year of £63,542. The model was sensitive to changes in assumptions regarding overall survival estimates and utility values. CONCLUSIONS: This study demonstrates the potential of using data for non-responders to model outcomes for BSC in cost-effectiveness evaluations based on single-arm trials. Further research is needed on the estimation of comparative effectiveness using uncontrolled clinical studies.

6.
BMC Health Serv Res ; 13: 60, 2013 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-23406481

RESUMO

BACKGROUND: Healthcare claims databases have been used in several studies to characterize the risk and burden of chemotherapy-induced febrile neutropenia (FN) and effectiveness of colony-stimulating factors against FN. The accuracy of methods previously used to identify FN in such databases has not been formally evaluated. METHODS: Data comprised linked electronic medical records from Geisinger Health System and healthcare claims data from Geisinger Health Plan. Subjects were classified into subgroups based on whether or not they were hospitalized for FN per the presumptive "gold standard" (ANC <1.0×10(9)/L, and body temperature ≥38.3°C or receipt of antibiotics) and claims-based definition (diagnosis codes for neutropenia, fever, and/or infection). Accuracy was evaluated principally based on positive predictive value (PPV) and sensitivity. RESULTS: Among 357 study subjects, 82 (23%) met the gold standard for hospitalized FN. For the claims-based definition including diagnosis codes for neutropenia plus fever in any position (n=28), PPV was 100% and sensitivity was 34% (95% CI: 24-45). For the definition including neutropenia in the primary position (n=54), PPV was 87% (78-95) and sensitivity was 57% (46-68). For the definition including neutropenia in any position (n=71), PPV was 77% (68-87) and sensitivity was 67% (56-77). CONCLUSIONS: Patients hospitalized for chemotherapy-induced FN can be identified in healthcare claims databases--with an acceptable level of mis-classification--using diagnosis codes for neutropenia, or neutropenia plus fever.


Assuntos
Antineoplásicos/efeitos adversos , Bases de Dados Factuais , Febre/induzido quimicamente , Febre/classificação , Revisão da Utilização de Seguros , Neutropenia/induzido quimicamente , Neutropenia/classificação , Idoso , Fatores Estimuladores de Colônias/uso terapêutico , Intervalos de Confiança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Sensibilidade e Especificidade
7.
Eur J Health Econ ; 13(5): 589-603, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21701940

RESUMO

BACKGROUND: In a phase III trial of women with HER2+ metastatic breast cancer (MBC) previously treated with trastuzumab, an anthracycline, and taxanes (EGF100151), lapatinib plus capecitabine (L+C) improved time to progression (TTP) versus capecitabine monotherapy (C-only). In a trial including HER2+ MBC patients who had received at least one prior course of trastuzumab and no more than one prior course of palliative chemotherapy (GBG 26/BIG 03-05), continued trastuzumab plus capecitabine (T+C) also improved TTP. METHODS: An economic model using patient-level data from EGF100151 and published results of GBG 26/BIG 03-05 as well as other literature were used to evaluate the incremental cost per quality-adjusted life-year [QALY] gained with L+C versus C-only and versus T+C in women with HER2+ MBC previously treated with trastuzumab from the UK National Health Service (NHS) perspective. RESULTS: Expected costs were £28,816 with L+C, £13,985 with C-only and £28,924 with T+C. Corresponding QALYs were 0.927, 0.737 and 0.896. In the base case, L+C was estimated to provide more QALYs at a lower cost compared with T+C; cost per QALY gained was £77,993 with L+C versus C-only. In pairwise probabilistic sensitivity analyses, the probability that L+C is preferred to C-only was 0.03 given a threshold of £30,000. The probability that L+C is preferred to T+C was 0.54 regardless of the threshold. CONCLUSIONS: When compared against capecitabine alone, the addition of lapatinib has a cost-effectiveness ratio exceeding the threshold normally used by NICE. Compared with T+C, L+C is dominant in the base case and approximately equally likely to be cost-effective in probabilistic sensitivity analyses over a wide range of threshold values.


Assuntos
Antimetabólitos Antineoplásicos/economia , Antineoplásicos/economia , Neoplasias da Mama/economia , Desoxicitidina/análogos & derivados , Fluoruracila/análogos & derivados , Quinazolinas/economia , Anticorpos Monoclonais Humanizados/economia , Anticorpos Monoclonais Humanizados/uso terapêutico , Antimetabólitos Antineoplásicos/uso terapêutico , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/psicologia , Capecitabina , Intervalos de Confiança , Análise Custo-Benefício , Desoxicitidina/economia , Desoxicitidina/uso terapêutico , Quimioterapia Combinada , Feminino , Fluoruracila/economia , Fluoruracila/uso terapêutico , Humanos , Lapatinib , Modelos Econômicos , Probabilidade , Anos de Vida Ajustados por Qualidade de Vida , Quinazolinas/uso terapêutico , Medicina Estatal , Trastuzumab , Reino Unido , Saúde da Mulher
8.
Clin Breast Cancer ; 10(4): 267-74, 2010 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-20705558

RESUMO

PURPOSE: The aim of this study was to estimate the cost-effectiveness of adding zoledronic acid 4 mg intravenously every 6 months to endocrine therapy in premenopausal women with hormone receptor-positive early breast cancer from a US health care system perspective. MATERIALS AND METHODS: A Markov model was developed to predict disease progression, mortality, and costs of breast cancer care for premenopausal women with hormone receptor-positive early breast cancer receiving up to 3 years of (1) endocrine therapy (goserelin plus tamoxifen or anastrozole); or (2) endocrine therapy plus zoledronic acid. Model parameters were obtained from ABCSG-12 (Austrian Breast and Colorectal Cancer Study Group Trial-12) and the literature. The incremental cost per quality-adjusted life year (QALY) gained with zoledronic acid was calculated under 2 scenarios: (1) benefits of zoledronic acid persist to maximum (7 years) follow-up in ABCSG-12 ("trial benefits") or (2) benefits persist until death ("lifetime benefits"). RESULTS: Adding zoledronic acid to endocrine therapy was projected to yield a gain of 0.41 life years (LYs) and 0.43 QALYs assuming trial benefits and 1.34 LYs and 1.41 QALYs assuming lifetime benefits. Assuming trial benefits, the incremental cost per QALY gained with zoledronic acid was $9300. Assuming lifetime benefits, zoledronic acid was estimated to increase QALYs and reduce costs. Cost per QALY gained was

Assuntos
Antineoplásicos Hormonais/economia , Protocolos de Quimioterapia Combinada Antineoplásica/economia , Neoplasias da Mama/tratamento farmacológico , Difosfonatos/economia , Imidazóis/economia , Anos de Vida Ajustados por Qualidade de Vida , Idoso , Antineoplásicos Hormonais/administração & dosagem , Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/economia , Análise Custo-Benefício , Difosfonatos/administração & dosagem , Difosfonatos/uso terapêutico , Feminino , Humanos , Imidazóis/administração & dosagem , Imidazóis/uso terapêutico , Cadeias de Markov , Pessoa de Meia-Idade , Pré-Menopausa , Ensaios Clínicos Controlados Aleatórios como Assunto , Ácido Zoledrônico
9.
Eur J Health Econ ; 11(1): 35-44, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19506926
10.
J Am Soc Nephrol ; 20(10): 2205-13, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19762496

RESUMO

The Aliskiren in the Evaluation of Proteinuria in Diabetes (AVOID) trial demonstrated that adding aliskiren, an oral direct renin inhibitor, at a dosage of 300 mg/d to the highest approved dosage of losartan and optimal antihypertensive therapy reduces albuminuria over 6 mo among patients with type 2 diabetes, hypertension, and albuminuria. The cost-effectiveness of this therapy, however, is unknown. Here, we used a Markov model to project progression to ESRD, life years, quality-adjusted life years, and lifetime costs for aliskiren plus losartan versus losartan. We used data from the AVOID study and the Irbesartan in Diabetic Nephropathy Trial (IDNT) to estimate probabilities of progression of renal disease. We estimated probabilities of mortality for ESRD and other comorbidities using data from the US Renal Data System, US Vital Statistics, and published studies. We based pharmacy costs on wholesale acquisition costs and based costs of ESRD and transplantation on data from the US Renal Data System. We found that adding aliskiren to losartan increased time free of ESRD, life expectancy, and quality-adjusted life expectancy by 0.1772, 0.1021, and 0.0967 yr, respectively. Total expected lifetime health care costs increased by $2952, reflecting the higher pharmacy costs of aliskiren and losartan ($7769), which were partially offset by savings in costs of ESRD ($4860). We estimated the cost-effectiveness of aliskiren to be $30,500 per quality-adjusted life year gained. In conclusion, adding aliskiren to losartan and optimal therapy in patients with type 2 diabetes, hypertension, and albuminuria may be cost-effective from a US health care system perspective.


Assuntos
Albuminúria/tratamento farmacológico , Amidas/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Fumaratos/uso terapêutico , Custos de Cuidados de Saúde , Hipertensão/tratamento farmacológico , Albuminúria/economia , Compostos de Bifenilo/uso terapêutico , Análise Custo-Benefício , Diabetes Mellitus Tipo 2/economia , Nefropatias Diabéticas/tratamento farmacológico , Progressão da Doença , Humanos , Hipertensão/economia , Irbesartana , Losartan/administração & dosagem , Losartan/uso terapêutico , Anos de Vida Ajustados por Qualidade de Vida , Tetrazóis/uso terapêutico
11.
Vaccine ; 27(36): 4930-7, 2009 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-19555715

RESUMO

Using a probabilistic model of the clinical and economic burden of rotavirus gastroenteritis (RVGE), we estimated the expected impact of vaccinating a US birth cohort with Rotarix in lieu of RotaTeq. Assuming full vaccination of all children, use of Rotarix - rather than RotaTeq - was estimated to reduce the total number of RVGE events by 5% and associated costs by 8%. On an overall basis, Rotarix would reduce costs by $77.2 million (95% CI $71.5-$86.5). Similar reductions with Rotarix were estimated to occur under an assumption of incomplete immunization of children.


Assuntos
Imunização/economia , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/prevenção & controle , Vacinas contra Rotavirus/economia , Vacinas contra Rotavirus/imunologia , Pré-Escolar , Análise Custo-Benefício , Feminino , Gastroenterite/epidemiologia , Gastroenterite/prevenção & controle , Humanos , Lactente , Recém-Nascido , Masculino , Modelos Estatísticos , Infecções por Rotavirus/economia , Estados Unidos/epidemiologia , Vacinas Atenuadas/economia , Vacinas Atenuadas/imunologia
12.
J Rheumatol ; 35(9): 1745-53, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18634164

RESUMO

OBJECTIVE: To assess cost-effectiveness of abatacept in patients with rheumatoid arthritis (RA) with inadequate response to tumor necrosis factor-alpha antagonists (anti-TNF). METHODS: We developed a simulation model to depict progression of disability [in terms of Health Assessment Questionnaire Disability Index (HAQ-DI)] in women aged 55-64 years with moderately to severely active RA and inadequate response to anti-TNF. At model entry, patients were assumed to receive either oral disease modifying antirheumatic drugs (DMARD) only or oral DMARD plus abatacept. Patients were then tracked from model entry until death. Future health-state utilities and medical-care costs (except study therapy) were estimated based on predicted values of the HAQ-DI. The model was estimated using data from a Phase III clinical trial of abatacept plus secondary sources. Cost-effectiveness was expressed in terms of incremental cost (2006 US$) per quality-adjusted life-year (QALY) gained alternatively over 10 years and a lifetime. Future costs and health effects were discounted at 3% annually. RESULTS: Over 10 years, abatacept would yield 1.0 additional QALY (undiscounted) per patient (4.0 vs 3.0 for oral DMARD) at an incremental (discounted) cost of $45,497 (100,648 vs $55,151) respectively; over a lifetime, corresponding figures were 1.6 QALY (5.8 vs 4.2) and $64,978 ($140,714 vs $82,489). Cost-effectiveness was [mean (95% CI)] $50,576 ($47,056, $54,944) per QALY gained over 10 years, and $45,979 ($42,678, $49,932) per QALY gained over a lifetime. Findings were robust in sensitivity analyses. CONCLUSION: Abatacept is cost-effective by current standards of medical practice in patients with moderately to severely active RA and inadequate response to an anti-TNF.


Assuntos
Antirreumáticos/economia , Artrite Reumatoide/economia , Imunoconjugados/economia , Fatores Imunológicos/economia , Abatacepte , Antirreumáticos/uso terapêutico , Artrite Reumatoide/fisiopatologia , Ensaios Clínicos Fase III como Assunto , Análise Custo-Benefício , Avaliação da Deficiência , Custos de Medicamentos/estatística & dados numéricos , Quimioterapia Combinada , Feminino , Humanos , Pessoa de Meia-Idade , Modelos Econométricos , Qualidade de Vida , Reumatologia/economia , Inquéritos e Questionários , Resultado do Tratamento , Fator de Necrose Tumoral alfa/antagonistas & inibidores
13.
Breast Cancer Res Treat ; 108(3): 375-87, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17653859

RESUMO

BACKGROUND: In the primary core analysis of BIG 1-98, a randomized, double-blind trial comparing 5 years of initial adjuvant therapy with letrozole versus tamoxifen in postmenopausal women with hormone receptor-positive (HR+) early breast cancer, letrozole significantly improved disease-free survival by 19% and reduced the risk of breast cancer recurrence by 28% and distant recurrence by 27%. METHODS: A Markov model was used to estimate the incremental cost per quality-adjusted life year (QALY) gained with 5 years of initial adjuvant therapy with letrozole versus tamoxifen from a Canadian healthcare system perspective. Probabilities of recurrence and side effects for tamoxifen were based on published results of BIG 1-98 and other published population-based studies. Corresponding probabilities for letrozole were calculated by multiplying probabilities for tamoxifen by estimated relative risks for letrozole versus tamoxifen from BIG 1-98. Other probabilities, costs of breast-cancer care and treatment of side effects, and health-state utilities were obtained from published studies. Costs and QALYs were estimated over the lifetime of a cohort of postmenopausal women with HR+ early breast cancer, aged 60 years at initiation of therapy, and discounted at 5% annually. RESULTS: Compared with tamoxifen, letrozole yields an additional 0.368 life-years (12.453 vs. 12.086) and 0.343 QALYs (11.582 vs. 11.239). These benefits are obtained at an additional cost of Can$ 8,110 (Can$ 30,819 vs. Can$ 22,709). Cost per QALY gained for letrozole versus tamoxifen is Can$ 23,662 (95% CI Can$ 15,667-Can$ 52,014). CONCLUSION: In postmenopausal women with HR+ early breast cancer, initial adjuvant treatment with letrozole is cost-effective from the Canadian healthcare system perspective.


Assuntos
Antineoplásicos Hormonais/economia , Neoplasias da Mama/tratamento farmacológico , Neoplasias Hormônio-Dependentes/tratamento farmacológico , Nitrilas/economia , Tamoxifeno/economia , Triazóis/economia , Antineoplásicos Hormonais/uso terapêutico , Canadá , Quimioterapia Adjuvante/economia , Análise Custo-Benefício , Custos de Medicamentos , Feminino , Humanos , Letrozol , Cadeias de Markov , Nitrilas/uso terapêutico , Pós-Menopausa , Anos de Vida Ajustados por Qualidade de Vida , Tamoxifeno/uso terapêutico , Triazóis/uso terapêutico
14.
Transfusion ; 47(10): 1919-29, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17880620

RESUMO

BACKGROUND: Patients with thalassemia major require iron chelation therapy (ICT) to prevent complications from transfusional iron overload. Deferoxamine is effective, but requires administration as a slow continuous subcutaneous or intravenous infusion five to seven times per week. Deferiprone is a three-times-daily oral iron chelator, but has limited availability in the United States. Deferasirox is a once-daily oral iron chelator that was approved in the United States in 2005 for patients older than 2 years of age with transfusional iron overload. STUDY DESIGN AND METHODS: Published evidence on rates of compliance with ICT and the association between compliance, and the incidence and costs of complications of iron overload, in patients with thalassemia major was reviewed. RESULTS: A total of 18 studies were identified reporting data on compliance with ICT, including 7 that examined deferoxamine only, 6 that examined deferiprone only, and 5 that compared deferoxamine and deferiprone; no studies reporting compliance with deferasirox were identified. In studies of deferoxamine only, estimated mean compliance ranged from 59 to 78 percent. Studies of deferiprone generally reported better compliance, ranging from 79 to 98 percent. Results of comparative studies of deferoxamine and deferiprone suggest that compliance may be better with oral therapy. Numerous studies demonstrate that that poor compliance with ICT results in increased risk of cardiac disease and endocrinopathies, as well as lower survival. Although data on the costs of noncompliance are limited, a recent model-based study estimated the lifetime costs of inadequate compliance with deferoxamine to be $33,142. CONCLUSIONS: Inadequate compliance with ICT in thalassemia major is common and results in substantial morbidity and mortality, as well as increased costs.


Assuntos
Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/prevenção & controle , Talassemia/terapia , Reação Transfusional , Recusa do Paciente ao Tratamento/estatística & dados numéricos , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Efeitos Psicossociais da Doença , Deferiprona , Desferroxamina/uso terapêutico , Humanos , Quelantes de Ferro/economia , Pessoa de Meia-Idade , Cooperação do Paciente , Piridonas/uso terapêutico , Talassemia/tratamento farmacológico , Talassemia/economia , Talassemia/psicologia
15.
Clin Breast Cancer ; 7(8): 608-18, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17592673

RESUMO

BACKGROUND: In Breast International Group (BIG) 1-98, a randomized, double-blind trial comparing 5 years of initial adjuvant therapy with letrozole versus tamoxifen in postmenopausal women with hormone receptor-positive early breast cancer, letrozole significantly improved disease-free survival by 19% and reduced risk of breast cancer recurrence by 28% and distant recurrence by 27%. PATIENTS AND METHODS: A Markov model was used to estimate the incremental cost per quality-adjusted life year (QALY) gained with 5 years of initial adjuvant therapy with letrozole versus tamoxifen from a US health care system perspective. Probabilities and costs of breast cancer recurrence and treatment-related adverse events and health-state utilities were based on published results of BIG 1-98 and other published studies. Costs and QALYs were estimated over the lifetime of a cohort of postmenopausal women with hormone receptor-positive early breast cancer, aged 60 years at initiation of therapy. In our base case, we assumed that benefits of letrozole on risk of breast cancer recurrence are maintained for 5 years after therapy discontinuation ("carry-over effect") and examined the effects of this assumption on results in sensitivity analyses. RESULTS: Under base-case assumptions, letrozole yields an additional 0.409 QALYs versus tamoxifen at an additional cost of $9705, yielding a cost per QALY gained for letrozole versus tamoxifen of $23,743 (95% confidence interval, $14,087-$51,129). Assuming no carry-over effects, letrozole yields 0.264 QALYs at a cost of $10,341, for a cost per QALY gained of $39,098 (95% confidence interval, $23,968- $83,501). CONCLUSION: In postmenopausal women with hormone receptor-positive early breast cancer, initial adjuvant treatment with letrozole is cost-effective from the US health care system perspective.


Assuntos
Antineoplásicos/economia , Neoplasias da Mama/tratamento farmacológico , Custos de Medicamentos , Neoplasias Hormônio-Dependentes/tratamento farmacológico , Nitrilas/economia , Anos de Vida Ajustados por Qualidade de Vida , Tamoxifeno/economia , Triazóis/economia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/uso terapêutico , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Quimioterapia Adjuvante , Análise Custo-Benefício , Feminino , Humanos , Letrozol , Cadeias de Markov , Pessoa de Meia-Idade , Modelos Econométricos , Neoplasias Hormônio-Dependentes/mortalidade , Neoplasias Hormônio-Dependentes/patologia , Nitrilas/efeitos adversos , Nitrilas/uso terapêutico , Pós-Menopausa , Ensaios Clínicos Controlados Aleatórios como Assunto , Tamoxifeno/efeitos adversos , Tamoxifeno/uso terapêutico , Triazóis/efeitos adversos , Triazóis/uso terapêutico
16.
Pharmacoeconomics ; 25(4): 329-42, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17402805

RESUMO

BACKGROUND: Deferasirox is a recently approved once-daily oral iron chelator that has been shown to reduce liver iron concentrations and serum ferritin levels to a similar extent as infusional deferoxamine. OBJECTIVE: To determine the cost effectiveness of deferasirox versus deferoxamine in patients with beta-thalassaemia major from a US healthcare system perspective. METHODS: A Markov model was used to estimate the total additional lifetime costs and QALYs gained with deferasirox versus deferoxamine in patients with beta-thalassaemia major and chronic iron overload from blood transfusions. Patients were assumed to be 3 years of age at initiation of chelation therapy and to receive prescribed dosages of deferasirox and deferoxamine that have been shown to be similarly effective in such patients. Compliance with chelation therapy and probabilities of iron overload-related cardiac disease and death by degree of compliance were estimated using data from published studies. Costs ($US, year 2006 values) of deferoxamine administration and iron overload-related cardiac disease were based on analyses of health insurance claims of transfusion-dependent thalassaemia patients. Utilities were based on a study of patient preferences for oral versus infusional chelation therapy, as well as published literature. Probabilistic and deterministic sensitivity analyses were employed to examine the robustness of the results to key assumptions. RESULTS: Deferasirox resulted in a gain of 4.5 QALYs per patient at an additional expected lifetime cost of $US126,018 per patient; the cost per QALY gained was $US28,255. The cost effectiveness of deferasirox versus deferoxamine was sensitive to the estimated costs of deferoxamine administration and the quality-of-life benefit associated with oral versus infusional therapy. Cost effectiveness was also relatively sensitive to the equivalent daily dose of deferasirox, and the unit costs of deferasirox and deferoxamine, and was more favourable in younger patients. CONCLUSION: Results of this analysis of the cost effectiveness of oral deferasirox versus infusional deferoxamine suggest that deferasirox is a cost effective iron chelator from a US healthcare perspective.


Assuntos
Benzoatos/economia , Benzoatos/uso terapêutico , Transfusão de Sangue/métodos , Triazóis/economia , Triazóis/uso terapêutico , Administração Oral , Benzoatos/administração & dosagem , Transfusão de Sangue/economia , Análise Custo-Benefício , Deferasirox , Atenção à Saúde/economia , Atenção à Saúde/métodos , Esquema de Medicação , Revisão de Uso de Medicamentos/estatística & dados numéricos , Farmacoeconomia/estatística & dados numéricos , Farmacoeconomia/tendências , Humanos , Infusões Intravenosas , Revisão da Utilização de Seguros/estatística & dados numéricos , Quelantes de Ferro/administração & dosagem , Quelantes de Ferro/economia , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/tratamento farmacológico , Cadeias de Markov , Resultado do Tratamento , Triazóis/administração & dosagem , Estados Unidos , Talassemia beta/tratamento farmacológico
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