Cost effectiveness of human immunodeficiency virus postexposure prophylaxis for healthcare workers

OBJECTIVE: The United States Public Health Service (USPHS) published recommendations for human immunodeficiency virus (HIV) postexposure prophylaxis (PEP) of healthcare workers in May 1998. The aim of this study was to analyse the cost effectiveness of the USPHS PEP guidelines. DESIGN AND SETTING: This was a modelling study in the setting of the US healthcare system in 1989. The analysis was performed from the societal perspective; however, only HIV healthcare costs were considered and health-related losses of productivity were not included. METHODS: A decision tree incorporating a Markov model was created for 4 PEP strategies: the current USPHS recommendations, triple drug therapy, zidovudine monotherapy or no prophylaxis. A probabilistic sensitivity analysis using a Monte Carlo simulation was performed. Confidence intervals (CIs) around cost-effectiveness estimates were estimated by a bootstrapping method. RESULTS: The costs (in 1997 US dollars) per quality-adjusted life-year (QALY) save by each strategy were as follows: monotherapy $US688 (95% CI: $US624 to $US750); USPHS recommendations $US5211 (95% CI: $US5126 to $US5293); and triple drug therapy $US8827 (95% CI: $US8715 to $US8940). The marginal cost per year of life saved was: USPHS recommendations $US81 987 (95% CI: $US80 437 to $US83 689); triple drug therapy $US970 451 (95% CI: $US924 786 to $US 1 014 429). Sensitivity testing showed that estimates of the probability of seroconversion for each category of exposure were most influential, but did not change the order of strategies in the baseline analysis. With the prolonged HIV stage durations and increased costs associated with recent innovations in HIV therapy, the marginal cost effectiveness of the USPHS PEP strategy was decreased to $US62 497/QALY saved. All 3 intervention strategies were cost effective compared with no postexposure prophylaxis. CONCLUSIONS: Current USPHS PEP recommendations are marginally cost effective compared with monotherapy, but the additional efficacy of triple drug therapy for all risk categories is rewarded by only a small reduction in HIV infections at great expense. For the foreseeable future, assuming innovations in therapy that employ expensive drug combinations earlier in the HIV disease course to extend life expectancy and the increasing prevalence of HIV drug resistance, our model supports the use of the USPHS PEP guidelines.     

Systemic therapy in breast cancer: efficacy and cost utility

Cancer treatment accounts for a large proportion of healthcare costs. Often, new treatment modalities provide benefits, but at high costs. The impression that cancer treatment is expensive is enhanced by publicity surrounding treatments like bone marrow transplantation. There is a need to evaluate costs of different treatment approaches and to address the cost utility of cancer treatment in general compared with therapies for other conditions. Breast cancer can serve as a good model for economic evaluation of cancer treatment because of the broad range of treatment options and objectives it encompasses, and also because well defined benefits can be achieved. The cost utility of contemporary adjuvant therapy strategies, specifically chemotherapy in premenopausal women and hormonal treatment in estrogen-receptor (ER) positive pre- as well as postmenopausal women, seems favourable. Cost-utility ratios {cost per quality-adjusted life-year (QALY) gained} range from $US4000 to $US10 000. However, hormonal treatment in ER-negative women may be associated with cost-per-QALY ratios of $US50 000 to $US200 000. So far there are no published cost-utility analyses of neo-adjuvant therapy or adjuvant bone marrow transplantation as the long term effects of these treatment options are undefined. Few data exist on cost utilities of systemic drug treatment in advanced breast cancer, although drugs may account for only a moderate part of the total treatment and caring costs. Bone marrow transplantation in patients with metastatic breast cancer costs about $US100 000 per QALY, which is expensive.     

Paclitaxel: a pharmacoeconomic review of its use in the treatment of ovarian cancer.

Paclitaxel belongs to the group of antitumour agents called the taxanes. Its efficacy in advanced ovarian cancer has been established in large, randomised phase III clinical trials. When used in combination with cisplatin for first-line treatment of advanced ovarian cancer, it is superior to cyclophosphamide/cisplatin, with gains in median survival of around 1 year. Paclitaxel plus carboplatin has similar efficacy to paclitaxel plus cisplatin. There is now consensus that paclitaxel plus either carboplatin or cisplatin is the recommended first-line therapy for patients with advanced ovarian cancer. The particular combination employed may vary between institutions and geographical regions, although paclitaxel plus carboplatin is generally better tolerated (i.e. lower incidence of non-haematological adverse events) than paclitaxel plus cisplatin and is widely used in many countries. Paclitaxel is also used as monotherapy in second-line (salvage) treatment of ovarian cancer. Pharmacoeconomic analyses performed to date have primarily focused on first-line therapy comparing the combination of paclitaxel/cisplatin with cyclophosphamide/cisplatin. All studies incorporated clinical outcomes data, most commonly from the Gynecologic Oncology Group (GOG) 111 trial, showing a survival advantage for paclitaxel/cisplatin. These studies report incremental cost-effectiveness ratios (ICERs) ranging from $US 6395 per additional life-year gained (LYG) in Spain (1995/96 values) to $US 44,690 per additional progression-free LYG in France (year of costs not reported). Five studies were based in the US and Canada and these reported very similar ICERs of $US 13,135 (year of costs not reported) to $US 25,131 (1993 costs) per additional LYG. In all of these studies the incremental costs of paclitaxel/cisplatin therapy fall well within the commonly cited threshold limit of $US 50,000 for new therapies and compare well with incremental costs reported for other oncological and life-saving therapies. Patient preferences and quality of life are important issues due to the short survival of patients with advanced ovarian cancer. Two cost-utility studies reported similar incremental cost-utility ratios (ICURs). In the study based on US costs, the ICUR of paclitaxel/cisplatin treatment was US $18,200 per additional quality-adjusted life-year (QALY) [1995 drug costs]. In a Canadian study the ICUR ranged from 11,600 Canadian dollars ($Can) to $Can 24,200 (1996 costs) per additional progression-free QALY depending on the choice of second-line treatment. CONCLUSIONS: Paclitaxel used in combination with cisplatin offers survival and utility gains versus cyclophosphamide plus cisplatin, when used as first-line treatment in patients with stage III or IV ovarian cancer. The incremental cost for these gains is within the accepted range for healthcare interventions. However, pharmacoeconomic analyses of paclitaxel plus carboplatin--a combination widely accepted for use in women with advanced ovarian cancer and with clinical advantages over paclitaxel plus cisplatin in terms of ease of administration and tolerability profile--are currently lacking. Nevertheless, results of available pharmacoeconomic data support the clinical use of paclitaxel/platinum combinations, particularly paclitaxel plus cisplatin, as a first-line chemotherapy treatment option in patients with advanced ovarian cancer.     

Cost effectiveness of acute imipramine therapy versus two imipramine maintenance treatment regimens for panic disorder

OBJECTIVE: To examine the medical costs and effectiveness of acute treatment with imipramine versus acute treatment plus 2 different maintenance therapies for panic disorder. METHODS: A clinical decision model was constructed to estimate 18-month costs and outcomes associated with these treatment scenarios based on the medical literature and clinician judgment. The clinical parameters and outcomes for the model were derived from a series of systematic clinical trials with imipramine utilising uniform dosage procedures and validated response criteria. Costs were calculated based on standardised treatment regimens. The outcome measures were 18-month medical costs, quality-adjusted life years (QALYs) and costs per QALY gained. A sensitivity analysis was performed to explore the impact of treatment withdrawals on outcomes. STUDY PERSPECTIVE: US mental healthcare system. RESULTS: Over 18 months, the total costs (1997 values) and QALYs associated with half-dose maintenance therapy (imipramine 1.1 mg/kg/day) [$US3377; QALYs = 0.991] and full-dose maintenance therapy (imipramine 2.25 mg/kg/ day) [$US3361; QALYs = 0.991] were almost identical; both were cost saving compared with acute imipramine therapy (2.25 mg/kg/day) with no maintenance treatment ($US3691; QALYs = 0.979). Whether patients withdrawing from treatment were considered to have continued to respond to treatment or to have relapsed, the half-dose and full-dose maintenance treatments were still cost saving compared with acute treatment alone. CONCLUSIONS: The results indicate that imipramine maintenance treatment is cost effective compared with acute imipramine treatment for patients with panic disorder. The basic findings and conclusions are not affected after modifying model assumptions for clinical response in patients withdrawing from treatment.     

Alglucerase. A pharmacoeconomic appraisal of its use in the treatment of Gaucher's disease

Alglucerase is a modified form of human placental glucocerebrosidase used as enzyme replacement therapy for patients with Gaucher's disease, in whom functional glucocerebrosidase is deficient. Alglucerase has provided a breakthrough in treatment for patients with this relatively rare disease. With alglucerase infusions typical disease manifestations are ameliorated or normalised: hepatosplenomegaly is reduced, haematological parameters improve, and patients experience an increased quality of life usually within 4 to 6 months of treatment. Parameters of bone disease also respond, but generally over a longer period of treatment. Alglucerase is well tolerated by children and adults, with few adverse effects reported. Seroconversion occurs in approximately 15% of patients on high-dose therapy, but does not appear to affect the efficacy of treatment. Several dosage regimens have been used to deliver alglucerase, and the comparative benefits of these remain controversial. High-dose regimens of 60 IU/kg bodyweight administered every 2 weeks are clearly effective; however, smaller dosages given more frequently are also effective and incur a greatly reduced acquisition cost. Patient responses are variable, and the dosage regimen should be tailored to individual needs. Dosage regimens may be considerably reduced for the maintenance phase of treatment, but clinical experience is as yet insufficient to establish the minimum dosages required in the long term. Acquisition cost of alglucerase is $US3.70 per unit (1994 US dollars); thus, a dosage regimen of 60 IU/kg bodyweight administered every 2 weeks for a patient weighing 70kg costs $US404,040 per year. The minimal costs per quality-adjusted life year saved (QALY) have been estimated for 3 dosage regimens over a 10-year period. Cost per QALY was $US147,000 for 60 IU/kg bodyweight administered every 2 weeks, $US75,000 for 30 IU/kg every 2 weeks, and $US49,000 for 2.3 IU/kg administered 3 times per week. These costs were calculated assuming immediate death with no treatment, which suggests that the actual costs per QALY for most patients with type 1 or 3 disease are likely to be much higher. Drug administration costs may become a significant part of the cost during maintenance therapy; in addition, possible cost savings due to increased patient productivity and reduced palliative treatments remain unresolved. Although some patients may obtain increased benefit from high-dosage regimens, the very high cost may preclude general use of these regimens. Healthcare resources consumed by alglucerase therapy represent a large opportunity cost for other therapeutic areas.(ABSTRACT TRUNCATED AT 400 WORDS)     

Healthcare resource and lost labour costs of migraine headache in the US

Migraine headache is responsible for significantly more healthcare resource and lost labour costs than previously reported. Costs associated with migraine were assessed via a survey conducted in 940 patients, 70% of whom responded. All met the International Headache Society's diagnostic criteria for migraine and had participated in one of two multicentre, single-dose, parallel-group, randomised, placebo-controlled clinical trials designed to assess the efficacy of an anti-migraine compound. Migraine frequency and costs, in terms of healthcare resource utilisation and lost labour (decreased productivity and missed workdays), were assessed. Over 90% of respondents visited a clinic and nearly 50% presented to an emergency room for treatment of migraine-related symptoms at least once in the year prior to the survey. These 648 respondents used an estimated $US529 199 per year in healthcare services. 89% of employed respondents reported that job performance was adversely affected by migraine and over 50% of them missed at least two days of work per month. Depending on the estimates used for migraine prevalence and using 1986 estimates of median earnings for the US work force, the extrapolated costs to employers ranged from $US5.6 billion to $US17.2 billion dollars annually due to decreased productivity and missed work days. The cost of migraine is not fully appreciated by the medical community or by society.     

The socioeconomic impact of insomnia. An overview

Insomnia is an extremely common symptom both de novo and in the context of other medical and psychiatric disorders. The impact of insomnia is often ignored both by the individual and by society in terms of its clinical and socioeconomic ramifications. Insomnia is therefore under-appreciated and almost certainly under-treated, thus making it a serious health concern. It is estimated that more than 60 million Americans suffer from insomnia annually, and this figure is expected to grow to 100 million by the middle of the 21st century. Whether it be difficulty initiating or maintaining sleep, the disruption of nocturnal sleep will invariably impact on daytime activities and often results in daytime fatigue, performance deficits (including memory and other cognitive deficits), an increase in the number of sick days taken by an individual and accidents (some catastrophic). This review examines the costs directly related to insomnia in various sectors of healthcare, the indirect costs associated with accidents, sick days and decreased work productivity, and related costs resulting from insomnia but which meet neither the criteria of direct nor indirect cost categories. The total direct, indirect and related costs of insomnia are conservatively estimated at $US30 to 35 billion annually in the US (1994 dollars). Economic gains can be made by treating patients on an outpatient basis in sleep centres.     

Atorvastatin: a pharmacoeconomic review of its use in the primary and secondary prevention of cardiovascular events

Atorvastatin is a lipid-lowering agent that has been evaluated in a number of primary and secondary intervention studies. In the primary prevention trials ASCOT-LLA and CARDS, atorvastatin 10 mg/day significantly reduced cardiovascular events compared with placebo. A prospectively conducted economic analysis of the 3.3-year ASCOT-LLA trial showed that atorvastatin was associated with incremental cost-effectiveness ratios (ICERs) of euro11,693 (UK) and euro12,673 (Sweden) per event avoided (2002 values). Longer-term modelled analyses using data from CARDS showed ICERs of euro8046 (Spain) and 6471pound (UK) per QALY gained (2003/2004 values), and a US analysis showed atorvastatin was dominant versus no statin when modelled over the lifetime of a representative US diabetic primary prevention population. In a modelled analysis based on results of the IDEAL trial, which showed significant reductions in cardiovascular endpoints with high-dose atorvastatin (80 mg/day) compared with conventional-dose simvastatin in patients with stable coronary heart disease, ICER values were below the commonly used cost-effectiveness threshold of euro50,000 per QALY gained in Norway, Sweden and Denmark, but were above this threshold in Finland (2005 values). A modelled US analysis that also included data from IDEAL and other sources showed an ICER of $US33,400 per QALY gained, assuming the incremental difference in acquisition cost between high-dose atorvastatin and conventional-dose simvastatin was $US1.40/day (2005 value). Most cost-effectiveness analyses with atorvastatin in patients with acute coronary syndrome used data from the 16-week MIRACL study, which showed a significant reduction in cardiovascular events with high-dose atorvastatin compared with placebo. Analyses were conducted in North America and Europe and showed that 31-86% of the acquisition cost of high-dose atorvastatin was offset by reductions in costs associated with cardiovascular events. Across five countries, ICER values ranged from approximate $US850 to $US4100 per event avoided (2000/2001 values). Another analysis conducted in the US used longer-term data and showed that high-dose atorvastatin versus conventional-dose statin was associated with an ICER of $US12,900 per QALY gained, assuming the daily difference in acquisition cost was $US1.40 (2005 value). In conclusion, atorvastatin has demonstrated beneficial effects on various cardiovascular endpoints in large, well designed primary and secondary intervention trials. These benefits in moderate- to high-risk patients were achieved at a relatively low incremental cost and, across the economic analyses, a substantial proportion of atorvastatin acquisition costs was offset by reductions in healthcare resource use associated with cardiovascular events. Cost-effectiveness analyses based on major clinical trials comparing atorvastatin with placebo, usual medical care, simvastatin or pravastatin have generally shown that atorvastatin is associated with favourable ICER values, often well below commonly used cost-effectiveness thresholds. These modelled analyses have the inherent limitation that projecting long-term outcomes beyond the time period of a clinical trial imparts a degree of uncertainty to the results. Nevertheless, while some findings were sensitive to changes in model assumptions, such as the long-term benefits of statin therapy, most sensitivity analyses showed that results of the base-case analyses were robust to plausible changes in key parameters. Although a clear pattern is not evident from available data, intuitively, the value of atorvastatin would be expected to increase with the patient's risk for serious cardiovascular events.     

An economic evaluation of atorvastatin for primary prevention of cardiovascular events in type 2 diabetes

OBJECTIVE: The CARDS trial, a multicentre, randomized, controlled trial, found that atorvastatin 10 mg/day for patients with type 2 diabetes mellitus and normal low-density lipoprotein (LDL)-cholesterol significantly reduced cardiovascular (CV) events, including stroke. We estimated the cost effectiveness of atorvastatin as primary prevention against CV disease from the short-term and lifetime US payer perspectives. RESEARCH DESIGN AND METHODS: We constructed a decision analytic (Markov) model to evaluate long-term costs and outcomes for atorvastatin 10 mg/day versus no HMG-CoA reductase inhibitor (statin) therapy for patients with type 2 diabetes and no history of a CV event. CV event rates and survival were based on risk equations calibrated to CARDS and applied to a US type 2 diabetes population; the atorvastatin effect on CV events was based on hazard ratios from CARDS; direct medical care costs were based on US treatment patterns and published costs analyses of patients with diabetes. Costs were valued in $US, year 2005 values; costs and benefits were discounted at 3% per annum. RESULTS: Within the time horizon of the trial (5 years), the cost effectiveness of atorvastatin was $US137 276 per QALY. At 10 years, the incremental cost per QALY improved to $US3640 per QALY. At 25 years, overall costs were lower and QALYs higher in the atorvastatin arm. Costs of managing CV events were lower after 5 years for patients treated with atorvastatin. CONCLUSIONS: For patients with type 2 diabetes and one additional risk factor for CV disease, normal LDL-cholesterol and no history of a CV event, primary prevention with atorvastatin appears to be cost saving and improve outcomes over 25 years, although it is costly from a short-term US payer perspective. From both a medical and an economic viewpoint, primary prevention is desirable in this patient population.     

Cost-of-illness of epilepsy in Italy. Data from a multicentre observational study (Episcreen)

OBJECTIVE: To investigate the impact of epilepsy in Italy on healthcare resources, producing an average cost per patient per year of follow-up. DESIGN AND SETTING: The Episcreen Project is a multicentre longitudinal Italian observational study; its methodology, organisational network and case report form have been reported in detail elsewhere. Using a subset of patients with epilepsy from this project, we conducted a retrospective cost-of-illness analysis based on clinical records. The analysis was performed from the societal (community) perspective, including both direct and indirect costs. Hospital admissions, day-hospital visits, specialist visits, instrumental examinations, drugs and productivity losses because of visits and hospitalisation were analysed. Each cost variable was valued in 1996 Italian liras (L) using published national tariffs (except for drugs for which published prices were used). A sensitivity analysis was conducted on indirect costs to test the robustness of the assumption that 1 working day lost for each day hospital visit would produce a change of 0.3% in the weight of indirect costs. PATIENTS AND PARTICIPANTS: Patients analysed in this study were registered in the Episcreen database as at 21 November 1996. They were diagnosed with epilepsy at the last visit, had at least 1 follow-up visit (i.e. at least 1 visit after the enrolment visit), and had at least 12 months of follow-up. RESULTS: The average cost per patient per year was L2,726,116 ($US1767). The average cost per patient was higher for children than for adults [L3,629,997 ($US2353) and L2,362,134 ($US1531), respectively), and for newly diagnosed patients for whom the first diagnosis of epilepsy was addressed at the first Episcreen visit [adults: old referrals L1,304,353 ($US845), new referrals L6,901,374 ($US4473); children: old referrals L2,810,504 ($US1822), new referrals L7,814,400 ($US5065)]. Direct costs represented 87.6% of total costs. The major cost driver was hospitalisation (63.7%), followed by drugs (10.5%), day-hospital visits (4.1%), out-patient visits (3.85%), other tests (3.1%) and electroencephalographs (2.3%). Indirect costs (lost productivity) represented 12.4% of total costs. Sensitivity analysis showed that the results are sensitive to the value attributed to lost productivity. CONCLUSIONS: The cost of managing a patient with epilepsy in Italy is influenced by age, syndrome and modality of referral to the centre for epilepsy.     

Healthcare costs of patients with heart failure treated with torasemide or furosemide

OBJECTIVE: To compare the direct healthcare costs of patients with congestive heart failure (CHF) prescribed torasemide (torsemide) or furosemide (frusemide). DESIGN AND SETTING: As part of a prospective, randomised, nonblind study, we assessed the effects of torasemide and furosemide on readmission to hospital in 193 patients treated for CHF at a US urban public healthcare system. We also calculated total direct healthcare costs for the 2 drugs. The perspective of the analysis was that of the healthcare system. Healthcare charge and utilisation data, demographic information, and health status data were obtained from an electronic database containing data for all patients treated within the healthcare system. PATIENTS AND PARTICIPANTS: Upon admission to the hospital, patients were eligible if they had evidence of left ventricular systolic dysfunction, were at least 18 years old, and were receiving furosemide. INTERVENTION: Inpatients were randomised to either torasemide or furosemide treatment for 1 year. MAIN OUTCOME MEASURES AND RESULTS: Patients treated with torasemide had fewer hospital admissions than those treated with furosemide [18 vs 34% for CHF (p = 0.013) and 38 vs 58% for any cardiovascular cause (p = 0.005)]. In the torasemide group, expected annual hospital costs per patient were lower for CHF admissions (by $US1054; 1998 values) and for all cardiovascular admissions (by $US1545) than in the furosemide group. Because the annual acquisition cost of torasemide was $US518 per patient higher than that of furosemide, the resulting net cost saving per patient was $US536 for CHF and $US1027 for all cardiovascular causes. Outpatient costs did not differ between treatment groups regardless of whether drug costs were considered. Total direct costs were $US2124 lower with torasemide than with furosemide (not statistically significant). CONCLUSIONS: Owing largely to reduced readmission to the hospital, the cost of inpatient care for patients with CHF is significantly lower with torasemide than with furosemide, despite the higher acquisition cost of torasemide. Treatment with torasemide resulted in a nonsignificant reduction in total direct costs (outpatient plus inpatient) compared with furosemide.     

Cost effectiveness of tumour necrosis factor-alpha inhibitors as first-line agents in rheumatoid arthritis

BACKGROUND AND OBJECTIVE: Rheumatoid arthritis (RA) is an autoimmune disease with an unknown aetiology that results in >9 million physician visits and >250 000 hospitalisations per year in the US. Tumour necrosis factor-alpha (TNFalpha) inhibitors are effective agents in treating RA; however, their cost effectiveness as first-line agents has not been investigated. This study aimed to examine the cost effectiveness of using TNFalpha inhibitors (both as monotherapy and in combination with methotrexate) as first-line agents versus methotrexate (monotherapy) from a payer perspective. METHODS: A Markov model was developed utilising a discount rate of 3% per annum, a cycle length of 1 year and a lifetime time-horizon for a hypothetical cohort of US females aged 55-60 years who had been diagnosed with RA. The source of data for predicted probabilities, expected mortality rates and treatment costs in year 2005 US dollars (drug, toxicity, monitoring and hospitalisation) was from the literature. These costs are assigned in 5-year cycles (calculated from initial 1-year estimates) along with the effect on quality-adjusted life-years (QALYs), which were calculated using the Health Assessment Questionnaire score. Univariate sensitivity analyses were conducted on all relevant parameters. RESULTS: Adalimumab, etanercept, adalimumab plus methotrexate and infliximab plus methotrexate had incremental cost-effectiveness ratios (ICERs) versus methotrexate monotherapy of $US63 769, $US89 772, $US194 589 and $US409 523 per QALY, respectively. When taking into consideration age at diagnosis, the ICER for etanercept ranged from $US84 129 to $US96 225 per QALY. In considering males for the base-case age at diagnosis, the ICER for etanercept versus methotrexate was $US85 100 per QALY. The average lifetime cost across all treatment arms in a woman diagnosed between 55 and 60 years of age was $US211 702. CONCLUSION: While these ICERs cannot be used to directly compare one biological agent with another since there are no comparative trials, they do provide a valid comparison versus methotrexate as first-line agents. Depending where the cost-effectiveness threshold is drawn (i.e. whether it is considered to be $US50 000 or $US100 000 per QALY), etanercept and adalimumab may be considered relatively cost-effective first-line treatments for RA compared with methotrexate monotherapy.     

Economic evaluation of vaccination

With increasing expenditures in healthcare, in absolute terms as well as in relative terms, interest in the efficiency of certain interventions in healthcare has also increased. Faced with the limitations of the healthcare budget, budget holders try to find the optimal way of dividing their funds over different healthcare provisions, without discarding human and medical considerations. In economic terms, this process could be called the 'optimal allocation of scarce resources over the inputs of a function of production'. The means of production would then be 'the provision of healthcare', whereas the output would be 'improvement of health'. Clearly choices have to be made with regard to spending the healthcare budget. One of the instruments that can help in making such choices is the economic evaluation. In economic evaluations of vaccinations, different vaccination strategies are defined. The consequences in terms of costs and effects of each strategy are being calculated and compared with a reference strategy, which is often the nonintervention strategy, i.e. 'no vaccination'. According to the way in which the benefit or the output of vaccination-'improvement of health'-is measured, a distinction is made between various methods of economic evaluation: in a cost-effectiveness analysis, health gains are measured in natural units (e.g. prevented infections, prevented illness days, life-years gained, etc.); in a cost-utility analysis, the quality of the health gains is taken into account (e.g. quality-adjusted life-year); and in a cost-benefit analysis, health gains are converted into monetary units. Costs can be divided into direct and indirect costs. Direct costs are directly related to medical treatments (medication, laboratory tests, consultations, etc.) or to vaccination (e.g. purchasing price of the vaccine, costs for administering the vaccine, treatment of side effects, etc.). Costs indirectly related to treatments and vaccination are mainly costs of lost productivity due to disease morbidity or mortality, and opportunity costs. In comparison with other vaccine-preventable infections, influenza vaccination for the elderly seems acceptable from an economic point of view (about $US650 per life-year gained, in 1981). Cost-effectiveness ratios of other vaccinations range from about $US720 per life-year gained for universal hepatitis B vaccination to about $US190,000 per life-year gained for universal Haemophilus influenzae type by vaccination. Because of differences in methods, the representation of results, and country-specific parameters, different economic evaluations of the same vaccination strategy may show divergent results. Therefore, until sufficient standardisation of economic evaluations exists, comparisons of the sort we are making here should be interpreted with prudence.     

Antiviral therapies for herpes zoster infections. Are they economically justifiable?

Antiviral treatment of herpes zoster is controversial because of uncertain benefits and relatively high costs. Most studies show that antiviral therapy lessens acute herpes zoster symptoms and postherpetic neuralgia (PHN). Current clinical recommendations support antiviral treatment of severely symptomatic herpes zoster in all adults, and mild herpes zoster in those 50 or 60 years of age or older. However, it is unclear if these recommended strategies are cost effective. Published studies of herpes zoster costs and the effect of antiviral therapy on costs and quality of life have significant variation in study design and results, as well as many shortcomings in the data. Thus, definitive economic recommendations cannot be made based on the present data. Another approach, which we have used, is to develop a 'reference case' analysis using decision-analysis techniques and the available data to estimate the incremental cost effectiveness of antiviral treatment in patients of differing age and herpes zoster severity. In the baseline analysis, parameter values and assumptions were consistently slightly biased against antiviral use. Effectiveness was measured in quality-adjusted life years (QALYs). We assumed that antiviral treatment did not change PHN risk, but decreased PHN duration in patients older than 50 years. PHN risk increased with age and with acute herpes zoster severity as seen in published data. Mild acute herpes zoster was assumed to have a utility value of 0.9 and severe acute herpes zoster a value of 0.7 on a scale where 0 = death and 1 = perfect health. Treating mildly symptomatic acute herpes zoster cost $US89,200/QALY gained in 40-year-olds, $US47,700/QALY in 60-year-olds and $US40,700/QALY in 70-year-olds (1995 values). Results were most sensitive to variation of antiviral costs (baseline $US134), but changes in acute symptom relief, PHN risk, duration, costs and utility, and antiviral effect on PHN duration increased costs/QALY above $US50,000 in 60- and 70-year-olds in extremes of parameter ranges. However, no variation resulted in treatment of mild illness in 40-year-olds to fall below $US50,000/QALY gained. Treatment of severe acute herpes zoster cost $US29,700, $US18,000 and $US16,500/QALY gained in 40-, 60- and 70-year-olds, respectively. Results were sensitive to variation of antiviral costs (> $US225) and acute symptom relief (< 21%) in 40-year-olds. Based on this analysis, antiviral therapy of herpes zoster seems economically justifiable for mildly symptomatic acute herpes zoster in patients aged 50 years and older, and for severely symptomatic acute herpes zoster in all adults.     

Olanzapine. A pharmacoeconomic review of its use in schizophrenia.

Olanzapine is an atypical antipsychotic agent which is at least as effective as the conventional agent haloperidol and the atypical agent risperidone. Olanzapine may be superior to haloperidol in some respects, including treatment of negative symptoms. A major advantage of olanzapine over haloperidol is its lower risk of extrapyramidal symptoms. Olanzapine improves quality of life and other aspects of functioning to a greater extent than haloperidol, and improves quality of life to at least the same extent as risperidone. However, olanzapine has a high acquisition cost compared with conventional antipsychotics. Despite this, most pharmacoeconomic analyses indicate that treatment with olanzapine does not significantly increase, and may even decrease, the overall direct treatment costs of schizophrenia, compared with haloperidol. Total direct medical costs calculated from prospective resource utilisation data were lower with olanzapine than with haloperidol by $US388 (1995 values) per patient over 6 weeks and by $US55 per patient per month during 46 weeks extended treatment. In a mixed effects linear model of the same data, total costs over 1 year were $US10,301 (1996 values) per patient lower with olanzapine than haloperidol, and olanzapine was associated with 18.3 more symptom-free days per patient. Compared with risperidone, mean total direct medical costs over 28 weeks were $US493 (1995 values) per patient lower with olanzapine. In a Markov model of 5 years' treatment, olanzapine was associated with more time in a disability-free state than haloperidol at a total cost per patient that was lower by $US1539 (1995 values), 816 Pounds (1995/1996 values), 977 Dutch guilders (NLG; 1995 values) and 2296 Deutschmarks in US, UK, Dutch and German analyses, respectively. In a similar Spanish analysis, the overall total cost was higher with olanzapine, giving an incremental cost effectiveness for olanzapine of 32,516 pesetas (1995 values) per month of disability-free time gained. When risperidone was a comparator, the total cost per patient was $US1875 and NLG202 lower with olanzapine in US and Dutch analyses, respectively. CONCLUSIONS: The high acquisition cost of olanzapine is offset by reductions in other treatment costs in patients with schizophrenia. Compared with haloperidol, the drug improved patient outcome and quality of life, while overall direct treatment costs were generally not increased, or even decreased. Olanzapine has also been reported to decrease overall treatment costs compared with risperidone, but confirmation is required. Olanzapine is a cost-effective alternative to conventional agents for the treatment of moderately to severely ill patients with longstanding schizophrenia.     

Infliximab: a pharmacoeconomic review of its use in rheumatoid arthritis

Infliximab (Remicade), a biological disease-modifying antirheumatic drug (DMARD), binds to and inhibits the activity of tumour necrosis factor-alpha, which is thought to play an important role in the pathophysiology of rheumatoid arthritis. Intravenous infliximab plus methotrexate is recommended in patients with rheumatoid arthritis who have not achieved satisfactory disease control with adequate courses of other DMARDs. Pharmacoeconomic analyses have been based on efficacy data from the pivotal placebo-controlled Anti-Tumour Necrosis Factor Trial in Rheumatoid Arthritis with Concomitant Therapy (ATTRACT) trial in patients with active, refractory rheumatoid arthritis. Infliximab every 8 weeks plus methotrexate demonstrated rapid and sustainable improvements in clinical response, delayed radiographic progression, and/or improved functional status and health-related QOL compared with placebo plus methotrexate at weeks 30, 54 and 102. In cost-utility analyses of infliximab plus methotrexate conducted from a healthcare payer and/or societal perspective in the US, Europe, Portugal, Sweden and the UK, infliximab 3 mg/kg every 8 weeks plus methotrexate was associated with acceptable (<$US50,000 per discounted QALY gained) cost-utility ratios relative to methotrexate alone in patients with active, refractory rheumatoid arthritis. When only direct costs were considered, the lifetime incremental cost per discounted QALY gained with infliximab plus methotrexate relative to methotrexate alone was $US30,500-38,700 (year of costing 1998 or not reported; treatment duration 54 or 102 weeks or lifelong) in the US and Europe analyses, and euro39 500 (year of costing not reported; lifelong treatment) in the Portuguese analysis. The cost-utility ratios were more favourable when lost productivity costs or the additional benefit of infliximab on radiographic stabilisation were considered. In the Swedish and UK analyses with a 10-year time horizon, infliximab plus methotrexate for 1 or 2 years was associated with cost-utility ratios of euro28 600-56 100 (year of costing not reported) when direct costs were considered, and euro3440-48 200 when direct costs plus loss-of-productivity costs were considered. In conclusion, cost-utility analyses, which were based on modelling of data from the pivotal clinical trial of infliximab plus methotrexate, indicate that infliximab plus methotrexate is associated with acceptable cost-effectiveness ratios (<$US50,000 per discounted QALY gained) relative to methotrexate monotherapy in patients with active rheumatoid arthritis who have not responded to previous methotrexate or other DMARD therapy. The cost effectiveness of infliximab versus other DMARDs is at present unclear, but will be clarified when appropriate data from directly comparative clinical and/or pharmacoeconomic studies become available. In patients in whom adequate courses of other DMARDs have failed to achieve satisfactory disease control, infliximab plus methotrexate may prevent or delay disability, which may produce reductions in nondrug costs that can help offset its acquisition cost.     

Cost-utility analysis of treatment with olanzapine compared with other antipsychotic treatments in patients with schizophrenia in the pan-European SOHO study

OBJECTIVE: To determine the cost utility of treating schizophrenic patients with olanzapine compared with other antipsychotics in a naturalistic outpatient setting. METHODS: The pan-European SOHO study is a 3-year, prospective, outpatient, observational study of outcomes associated with antipsychotic treatment, focusing on olanzapine, in ten European countries. For the cost-utility analysis, healthcare resource use (inpatient care, day care, outpatient psychiatric consultations and antipsychotic and concomitant medication use) and EQ-5D data were collected at baseline and at 3, 6 and 12 months. The perspective was that of the health service payer. UK healthcare unit costs (year 2004 values) were applied to the resource use data for the ten countries. UK population tariffs were applied to the EQ-5D data to determine utility values.An Epoch analysis was used to analyze the longitudinal data. Multivariate regression analyses that adjusted for baseline covariates were used to estimate the incremental cost and utility gains for patients treated with olanzapine compared with each of the other antipsychotics (risperidone, quetiapine, amisulpride, clozapine and oral or depot typical antipsychotics). RESULTS: A total of 10 972 patients were enrolled at baseline, of which 9107 completed the 12-month study period. Treatment with olanzapine was more effective in terms of QALYs gained than all of the other antipsychotic treatments. Treatment with olanzapine dominated quetiapine and amisulpride. The incremental cost for olanzapine compared with risperidone was pound sterling 226 per patient over 12 months and the incremental cost per QALY gained was pound 5156, with bootstrap analyses showing 100% of the replications falling below a pound sterling 30 000 per QALY gained threshold. Compared with treatment with clozapine, olanzapine was found to be marginally more effective, at an additional cost of pound sterling 13 per patient over 12 months and to have an incremental cost per QALY gained of pound sterling 775. Bootstrap analyses showed that 81% of replications fell below a pound sterling 30 000 per QALY gained threshold. Comparing olanzapine with oral and depot typical antipsychotics, the incremental cost was pound sterling 849 and pound sterling 1106 per patient over 12 months and the incremental cost per QALY gained was pound sterling 15 696 and pound sterling 23 331, respectively. Bootstrap analyses showed that 98% of the replications fell below a pound sterling 30 000 per QALY gained threshold for the comparison with oral typical antipsychotics, and 79% of replications for the comparison with depot preparations. CONCLUSIONS: Among SOHO patients, if a funding threshold of pound sterling 30 000 per QALY gained is assumed, this analysis suggests that olanzapine has a high probability of being the most cost-effective treatment compared with other antipsychotic treatments. However, comparison of olanzapine with clozapine and typical depot antipsychotics should be viewed with caution because clozapine is a second-line treatment and depot treatment is used for patients who do not adhere to their oral medication.     

Review of cost-benefit analyses of influenza vaccine

Vaccination is an underutilised, low cost and effective method of preventing illness. Cost-effectiveness analysis discloses a beneficial role of influenza vaccination in preventing illness especially in patients over 65 years of age and in high risk patients. In one large study, when 150 million doses of influenza vaccine were given between 1971 and 1977 in the US, over 13 million more years of life were gained at a cost of only $US63 per year of life gained (1978 dollars). The vaccination programmes also resulted in productivity gains of approximately 5 million days which was valued at $US250 million. Other studies from Canada, Finland and the US found similar benefits. The findings of these studies are reviewed. In order to increase the use of influenza immunisation substantially, there has to be a greater acceptance of the value of immunisation by healthcare providers and the public.     

Cost effectiveness of pramipexole in Parkinson's disease in the US.

OBJECTIVE: Pramipexole was recently approved in the US for treatment of the symptoms of idiopathic Parkinson's disease (PD). Although pramipexole has been found to be safe and efficacious when compared with placebo, little data are yet available on its cost effectiveness when compared with baseline treatment. The aim of this study was to estimate the costs and cost effectiveness (cost utility) of pramipexole compared with baseline treatment in patients with early and advanced PD. DESIGN AND SETTING: We developed a cost-effectiveness (CE) model in the US setting that linked Unified Parkinson's Disease Rating Scale (UPDRS) Part II (activities of daily life) and III (motor) scores to disease progression, costs and patient utility. Data for the model were obtained from clinical trials, a literature review and a survey of 193 patients' health resource use and utility. We used cost and quality-adjusted life-year (QALY) estimates from the model to estimate the incremental cost effectiveness of pramipexole relative to baseline treatment patterns. We performed separate analyses for patients with early and advanced PD. We also performed extensive sensitivity analyses by adding other dopamine agonists to the no-pramipexole treatment regimen and varying disease progression parameters. The study was conducted from the societal perspective, although data presentation allows interpretation of cost effectiveness from either the societal or payer perspective. MAIN OUTCOME MEASURES AND RESULTS: For patients with both early and advanced PD, treatment with pramipexole had higher costs but was more effective than baseline treatment. For patients with early onset of PD, the incremental total CE ratio for pramipexole was $US8837/QALY. For patients with advanced PD, the incremental CE ratio was $US12 294/QALY (1997 costs). These ratios were lower than the CE ratios of many widely used medical treatments. CONCLUSIONS: Subject to the inherent limitations of modelling chronic disease progression and subsequent healthcare costs and patient utility, the results suggested that pramipexole was a cost effective treatment for patients with early and advanced PD in the US.