RESUMEN
BACKGROUND: There is evidence that utility elicitation methods used in the calculation of quality-adjusted life years (QALYs) yield different results. It is not clear how these differences impact economic evaluations. METHODS: Using a mathematical model incorporating data on efficacy, costs, and utility values, we simulated the experiences of 100,000 hypothetical rheumatoid arthritis patients over 10 years (50,000 exposed to infliximab plus methotrexate [MTX] and 50,000 exposed to MTX alone). QALYs, were derived from the Health Utilities Index 2 and 3 (HUI2 and HUI3), the Short Form 6-D (SF-6D), and the Euroqol 5-D (EQ-5D). Incremental cost-utility ratios were determined using each instrument to calculate QALYs and the results were compared using cost-effectiveness acceptability curves. RESULTS: Using the different utility measurement methods, the mean difference in QALYs between the infliximab plus MTX and MTX groups ranged from a high of 1.95 QALYs (95% CI=1.93-1.97) using the HUI3 to 0.89 QALYs (95% CI=0.88-0.91) using the SF-6D. Adopting the commonly cited value of society's willingness to pay for a QALY of $50,000, 91% of the simulations favored the cost utility of infliximab plus MTX when using the HUI3 to calculate QALYs. However, when using the EQ-5D, HUI2, or the SF-6D utility values to calculate QALYS, the proportion of simulations that favored the cost utility of infliximab were 63%, 45%, and 12%, respectively. CONCLUSION: Depending on the method for determining utility values used in the calculation of QALYs, very different incremental cost-utility ratios are generated.
Asunto(s)
Artritis Reumatoide/economía , Años de Vida Ajustados por Calidad de Vida , Anticuerpos Monoclonales/economía , Anticuerpos Monoclonales/uso terapéutico , Antirreumáticos/economía , Antirreumáticos/uso terapéutico , Artritis Reumatoide/rehabilitación , Análisis Costo-Beneficio , Interpretación Estadística de Datos , Quimioterapia Combinada , Humanos , Infliximab , Cadenas de Markov , Metotrexato/economía , Metotrexato/uso terapéutico , Modelos Estadísticos , Análisis de Supervivencia , Factores de TiempoRESUMEN
OBJECTIVE: To estimate survival, the number of life-years gained and cost effectiveness of antiretroviral therapy (ART) regimens, denoted as ERA-I [zidovudine + (didanosine or zalcitabine)]; ERA-II [stavudine + (didanosine or zalcitabine) or lamivudine + (zidovudine or didanosine or zalcitabine or stavudine)]; and ERA-III [2 nucleoside reverse transcriptase inhibitors + (1 protease inhibitor or 1 non-nucleoside reverse transcriptase inhibitor)]. DESIGN: Modelling of drug cost, cost of opportunistic diseases and survival of HIV positive men and women in the province of British Columbia who were first prescribed any ART between October 1992 and June 1996. A 'reference cohort' was modelled upon individuals in a longitudinal cohort of homosexual men followed since 1982. PERSPECTIVE AND SETTING: Third-party payer perspective in British Columbia, Canada. PATIENTS: All HIV-positive men and women aged > or =18 years with CD4+ counts < or =350 cells/microL who were enrolled in the province-wide drug treatment programme. MAIN OUTCOME MEASURES: Annual costs, survival and cost-effectiveness ratios of successive ART regimens. RESULTS: Total costs [1997 Canadian dollars ($Can)] at 12 months under ERA-I, -II and -III were $Can4897, $Can6620 and $Can 11 914, respectively. Survival at 12 months under ERA-I, -II and -III was 89.6%, 91.0% and 97.6%, respectively. The annual incremental cost (estimated by the total incremental cost at 12 months) between ERA-II and ERA-I was $Can1723. The incremental cost-effectiveness ratios between ERA-III and ERA-I, and between ERA-III and ERA-II were $Can58 806 and $Can46 971 per life-year gained, respectively. CONCLUSION: We found the cost effectiveness of ERA-III ART regimens well within the range of currently funded therapies for the treatment of other chronic diseases.
Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/tratamiento farmacológico , Fármacos Anti-VIH/administración & dosificación , Adulto , Análisis Costo-Beneficio , Quimioterapia Combinada , Femenino , Costos de la Atención en Salud , Humanos , Masculino , Persona de Mediana EdadRESUMEN
OBJECTIVE: The average per person direct cost of illness of cardiorespiratory disease episodes was estimated based on a prospective study of emergency department visits. METHODS: Economic modelling of health care costs using prospectively collected resource utilization data (9/1/94 to 8/31/95) from hospital emergency department visitors assigned a diagnosis of asthma, chronic obstructive pulmonary disease (COPD), respiratory infections or cardiac conditions. RESULTS: The total direct costs (1997 CDN$) [95% C.I.] per patient were $1,043.55 [$922.65, $1,164.47] for asthma, $1,690.11 [$1,276.92, $2,103.30] for COPD, $676.50 [$574.46, $778.54] for respiratory infections, and $3,318.74 [$2,937.72, $3,699.76] for cardiac conditions. CONCLUSIONS: This study showed that on average, patients diagnosed with a cardiac condition had the highest total direct cost. Hospitalization cost was the largest component of costs for all diagnoses except asthma, for which medications were the single largest component of direct costs.
Asunto(s)
Asma/economía , Costo de Enfermedad , Servicio de Urgencia en Hospital/economía , Episodio de Atención , Cardiopatías/economía , Enfermedades Pulmonares Obstructivas/economía , Infecciones del Sistema Respiratorio/economía , Adulto , Anciano , Asma/terapia , Niño , Preescolar , Servicio de Urgencia en Hospital/estadística & datos numéricos , Femenino , Humanos , Enfermedades Pulmonares Obstructivas/terapia , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Infecciones del Sistema Respiratorio/terapiaRESUMEN
This study is to update the estimates of the economic burden of illness because of overweight and obesity in Canada by incorporating the increase in prevalence of overweight and obesity, findings of new related comorbidities and rise in the national healthcare expenditure. The burden was estimated from a societal perspective using the prevalence-based cost-of-illness methodology. Results from a literature review of the risks of 18 related comorbidities were combined with prevalence of overweight and obesity in Canada to estimate the extent to which each comorbidity is attributable to overweight and obesity. The direct costs were extracted from the National Health Expenditure Database and allocated to each comorbidity using weights principally from the Economic Burden of Illness in Canada. The study showed that the total direct costs attributable to overweight and obesity in Canada were $6.0 billion in 2006, with 66% attributable to obesity. This corresponds to 4.1% of the total health expenditures in Canada in 2006. The inclusion of newly identified comorbidities increased the direct cost estimates of obesity by 25%, while the rise in national healthcare expenditure accounted for a 19% increase. Policies to reduce being overweight and obese could potentially save the Canadian healthcare system millions of dollars.
Asunto(s)
Costos de la Atención en Salud , Obesidad/economía , Obesidad/epidemiología , Sobrepeso/economía , Sobrepeso/epidemiología , Índice de Masa Corporal , Canadá/epidemiología , Comorbilidad , Costo de Enfermedad , Femenino , Costos de la Atención en Salud/estadística & datos numéricos , Encuestas Epidemiológicas , Humanos , Masculino , Obesidad/complicaciones , Sobrepeso/complicacionesRESUMEN
BACKGROUND: Each province in Canada independently assesses drugs for their reimbursement eligibility. Publicly funded access to specific drugs is therefore dependent on province of residence. OBJECTIVE: Evaluate the variability of access and its determinants for publicly available prescription drugs across Canada, and discuss the feasibility of implementing a national plan. METHODS: For a sample of 58 drugs receiving Health Protection Branch approval in Canada between 01/01/1996 and 12/31/1997, all provinces were surveyed about their formulary inclusion/exclusion decision. Kappa values were estimated to measure concordance between provincial coverage decisions. Logistic analysis using Generalized Estimating Equations was used to assess the impact of key features of provincial plans on the decision. RESULTS: Among the 58 drugs, 5 (9%) were included in all 10 and 14 (24%) by at least 8 provincial formularies. None were excluded by all the provinces. Concordance rates among provinces were low (overall kappa-like statistic = 0.20 and range of pairwise kappa = -0.11 to 0.64). Logistic regression showed that therapeutic category, price ratio to comparator, the integration of public with private coverage, and the existence of ability-to-pay criteria were significant determinants of the inclusion decision. CONCLUSIONS: Findings show that public access to the same prescription medications differs widely across provinces. If Canada were to adopt a "National" plan without disrupting current individual prescriptions, all currently funded drugs in each province would have to be "grandfathered" and included in the new National formulary. Such an all-inclusive list would also make such a plan unaffordable.
Asunto(s)
Cobertura del Seguro/estadística & datos numéricos , Seguro de Servicios Farmacéuticos/estadística & datos numéricos , Canadá , Formularios Farmacéuticos como Asunto , Accesibilidad a los Servicios de Salud , Humanos , Modelos LogísticosRESUMEN
OBJECTIVE: To determine factors associated with response or toxicity to cyclosporin A (CSA) in a population-based inception cohort with rheumatoid arthritis (RA). METHODS: Prospectively collected longitudinal measures including tender joint count (JC), duration of morning stiffness (MS), systolic and diastolic blood pressure (SBP, DBP), and serum creatinine (SCr) were modeled using generalized estimating equations. Survival methods were used to estimate CSA continuation time and its determinants. RESULTS: Of 133 patients (75% female, median RA duration 13 years), 37 discontinued CSA because of ineffectiveness (19) or because of toxicity (18) including increased SCr in 10, hypertension in 4, infections in 3, and gingival hyperplasia in 1. Patients remained on CSA a median of 75 months (95% confidence interval [CI] 38-112). Those receiving concomitant methotrexate (MTX) were more than 4 times as likely to continue on CSA therapy (hazard ratio 0.22, 95% CI 0.10-0.94). A lower final JC was predicted by a longer CSA treatment duration (relative risk [RR] 0.99 per month, 95% CI 0.98-0.99) and concomitant MTX therapy (RR 0.79, 95% CI 0.63-0.99); decreased MS was predicted only by longer CSA treatment duration (reduction of 2.0 minutes per month, 95% CI 1.1-3.0). Each previous disease-modifying antirheumatic drug (DMARD) exposure predicted a rise in SCr (35 micromole/liter, 95% CI 22-48), SBP (7.2 mm Hg, 95% CI 2.7-11.7), and DBP (3.8 mm Hg, 95% CI 3.0-6.4). CONCLUSIONS: Combination CSA/MTX prolongs therapy and reduces JC. Long-term CSA treatment was fairly well tolerated. Previous DMARD use appears to be a determinant for the development of toxicity.