Biomedical subjects

B A van Hout

Publications and source records attributed to B A van Hout.

At least 19 recordsLinked to original sources

PubMed2001

Comparison of coronary-artery bypass surgery and stenting for the treatment of multivessel disease.

BACKGROUND: The recent recognition that coronary-artery stenting has improved the short- and long-term outcomes of patients treated with angioplasty has made it necessary to reevaluate the relative benefits of bypass surgery and percutaneous interventions in patients with multivessel disease. METHODS: A total of 1205 patients were randomly assigned to undergo stent implantation or bypass surgery when a cardiac surgeon and an interventional cardiologist agreed that the same extent of revascularization could be achieved by either technique. The primary clinical end point was freedom from major adverse cardiac and cerebrovascular events at one year. The costs of hospital resources used were also determined. RESULTS: At one year, there was no significant difference between the two groups in terms of the rates of death, stroke, or myocardial infarction. Among patients who survived without a stroke or a myocardial infarction, 16.8 percent of those in the stenting group underwent a second revascularization, as compared with 3.5 percent of those in the surgery group. The rate of event-free survival at one year was 73.8 percent among the patients who received stents and 87.8 percent among those who underwent bypass surgery (P<0.001 by the log-rank test). The costs for the initial procedure were $4,212 less for patients assigned to stenting than for those assigned to bypass surgery, but this difference was reduced during follow-up because of the increased need for repeated revascularization; after one year, the net difference in favor of stenting was estimated to be $2,973 per patient. CONCLUSION: As measured one year after the procedure, coronary stenting for multivessel disease is less expensive than bypass surgery and offers the same degree of protection against death, stroke, and myocardial infarction. However, stenting is associated with a greater need for repeated revascularization.

Adult↗

PubMed2001

Cost-effectiveness of HMG coenzyme reductase inhibitors; whom to treat?

AIMS: Treatment guidelines have been developed for both "primary" and "secondary" prevention of coronary heart disease. These should consider both the efficacy as well as the costs of such treatment, particularly the costs of treatment with HMG co-enzyme A reductase inhibitors (statins). In the context of guideline development in The Netherlands, the cost effectiveness of treatment with statins was analysed. METHODS: Following a modelling approach, cost effectiveness was analysed as a function of a patient's initial risk for new coronary heart disease events, combining results from 4S, CARE, LIPID, WOSCOPS and AFCAPS with Dutch cost data. For each sex and age group, an estimate was made of the level of cardiovascular risks that might correspond to a cost-effectiveness ratio under NLG 40 000 (Euro 18 151) per life year gained. RESULTS: If the 10-year risk of myocardial infarction, stroke or cardiovascular death was estimated at 9% (AFCAPS/TexCAPS), 20% (WOSCOPS), 36% (CARE) 36% (LIPID) and 47% (4S), cost effectiveness was estimated at Euro 51 400, Euro 26 013, Euro 9970, Euro 8028 and Euro 6695. The arbitrary threshold of NLG 40 000 (approximately Euro 18 000) was achieved at a 10 year coronary heart disease event risk ranging from 19% to 26% for different age groups. Assuming the effectiveness of statin treatment decreased with age, a 10-year risk, corresponding to Euro 18 000, varied from 11% (under age 30) to 41% (over age 80). Patients at higher risk levels should be considered for statin therapy. CONCLUSIONS: Treatment costs for primary or secondary prevention are determined predominantly by the costs of statin drugs. The developed model allows comparison of cost effectiveness of statin therapy across a wide range of subjects with or without coronary heart disease. The consensus committee in the Netherlands postulated that drug therapy should be considered in subjects with or without coronary heart disease in which cost-effectiveness is similar. Such groups can be identified using the presented model. When cost effectiveness ratios up to Euro 18 000 per life year gained are deemed acceptable, statin treatment should be considered in most patients with known cardiovascular disease (secondary prevention), and in a limited group of subjects who are at high risk of developing coronary heart disease (primary prevention).

Analysis of Variance↗

PubMed2001

Costs in the last year of life in The Netherlands.

The costs of health care in the last year of life are a subject of debate and myth. Expensive interventions at the end of life often are blamed for the rapid increase in health care spending, but evidence about the existence of such exceptionally high expenditures at the end of life is rare and faulty. This investigation examines the development and composition of health care costs at the end of life for all age groups in The Netherlands. In contrast with earlier studies, this research analyzes both acute care (cure) and long-term care (care) costs. As an alternative for the frequently used concept of calendar years, we employed the concept of life years for calculating the costs at the end of life. We found that when life approaches its end, health care expenditures indeed rise sharply, especially in the last months. However, when we compared total cure costs in the last year of life to the total cure costs for the entire population, we concluded that the end-of-life share was only about 10%. Results of this study show that interventions to reduce costs in the last year of life will have only a modest impact compared to the total health care budget.

Acute Disease↗

PubMed2000

Diabetes nephropathy in the Netherlands: a cost effectiveness analysis of national clinical guidelines.

BACKGROUND: In the Netherlands a program on quality assurance in medical care has started in 1996. Clinical professionals, patient organizations and health services researchers formulate evidence based guidelines with a concomitant cost-effectiveness analysis. OBJECTIVES: To examine the cost-effectiveness of guideline recommendations for prevention of nephropathy in diabetes mellitus type 1 and 2. RESEARCH DESIGN: A semi-Markov compartment model was developed. Data from international publications on epidemiological surveys and randomized trials, together with national data on health care use and costs, were used to feed the model. A cohort of diabetes patients without renal disease enters the model. MEASURES: Complication (end-stage renal disease) free years, QALY's, and life-time medical costs per patient treated according to guideline recommendations or current anti-diabetic strategy. RESULTS: Guideline treatment for type 1 diabetes yields 4.2 complication free life years, at a cost-effectiveness ratio of 13 500 (Dutch guilders) NLG per QALY. Type 2 diabetes patients gain 0.2 complication free life years at a cost-effectiveness ratio of 31 000 NLG per QALY. CONCLUSION: Guideline development for diabetes nephropathy, with concomitant cost-effectiveness calculations, has resulted in a transparent guideline with explicit information on long-term cost and effects. The project has brought health care providers and health services researchers together.

Adolescent↗

PubMed1999

The ARTS study (Arterial Revascularization Therapies Study).

The rising costs of health care have forced policy makers to make choices, and new treatments are increasingly assessed in terms of the balance between additional costs and additional effects. The recent recognition that stenting has a major and long-lasting effect enhancing balloon PTCA procedure has made it imperative to compare in patients with multivessel disease the standard surgical procedure with multiple stenting in a large scale multinational and multicentre approach (19 countries, 68 sites). Selection and inclusion of patients is based on a consensus of the cardiac surgeon and interventional cardiologist on equal 'treatability' of patients by both techniques with analysis of clinical follow-up (event-free survival) on the short (30 day), medium (1 year), and long-term (3 and 5 year) with analysis of cost-effectiveness and quality of life (EuroQol and SF-36). Of the entire trial, the primary null hypothesis which needs to be rejected is that there will be no difference in event-free survival or effectiveness (E), at 1 year and also that the direct and indirect costs (C) per event-free year are not different between surgery or stenting. For this to become significant with a power of 90% one needs 1200 patients. Between April 97 and June 98, 1205 patients have been randomized with a monthly recruitment of 83 patients. Expected costs, effects and cost-effectiveness ratio (CE ratio) are: Stent high costs 2 VDStent high costs 3 VDStent low costs 2 VDStent low costs 3 VDCABG costs (C)$19.297$24.566$16.638$20.456$21.350 effects (E)81%81%81%81%88% CE ratio$23.876$30.397$20.586$25.322$24.348 Clinically, stenting is not expected to be more effective than CABG, but should be cost effective in both the 2- and 3-VD group when using the lower cost estimate and in the 2 VD group when using the higher cost assumptions.

Angioplasty, Balloon, Coronary↗

PubMed1999

Incremental cost of medical care after hip fracture and first vertebral fracture: the Rotterdam study.

The aim of this study was to estimate the additional cost of medical care (the incremental cost) caused by incident hip and vertebral fractures, using a matched case cohort design within a longitudinal follow-up study. Incident hip fractures were recorded using the regular follow-up system of the Rotterdam Study. Incident vertebral fractures were recorded by morphometric comparison of spinal radiographs taken at intervals of 2.2 years on average. The matched control group was randomly selected from other participants of the Rotterdam Study in whom no fracture occurred during follow-up, but who were otherwise comparable at baseline. Cases were matched for age, gender, self-perceived health, ability to perform activities of daily life, living situation and general practitioner. Medical expenditure was assessed by retrieval of the general practice medical records and by recording all hospital and nursing home admissions, and all general practice and outpatient visits. Pharmaceutical consumption was recorded through the computerized records of the central pharmacy. Valid results were obtained for 44 pairs (91%) in the hip fracture and for 42 pairs (93%) in the vertebral fracture group. Cost of medical consumption in the year before the hip fracture was similar in patients and control subjects, but the incremental cost in the first year after the hip fracture was almost US$10 000. In the second year after hip fracture the incremental cost was still about $1000. Accounting for the excess mortality in hip fracture patients had little effect on cost in the first year, but cost in the second year was doubled to almost $2000. For vertebral fractures, we did not detect important acute care costs, but these fractures were associated with a yearly recurrent incremental cost of over $1000. However, almost half this difference was already present before the occurrence of the fracture, and was attributable to hospital admissions. The remainder of the incremental cost was mainly due to pharmaceutical consumption and to a lesser extent to admissions to orthopedic surgery wards. We conclude that hip fractures cause excess mortality and an important incremental cost especially during the first year, and that these could probably be avoided by prevention of hip fractures. For vertebral fractures we found no evidence of important acute care costs but we observed a yearly returning incremental cost. Part of this incremental cost, however, was pre-existing and might therefore by caused by co-morbidity.

Aged↗

PubMed1999

Estimating parametric relationships between health description and health valuation with an application to the EuroQol EQ-5D.

Generic health status measures classify patients into different health states. For example, the EQ-5D descriptive system developed by the EuroQol Group classifies patients into 243 health states. Empirical values for the health states are available for only a selection (mostly 12 to 45) of these health states. Several parametric relationships between the descriptive system and the known values can be formulated to estimate the values for the unrecorded health states. This paper describes several of these modeling exercises in a comprehensible way, using the EQ-5D as an illustration. It is shown that the estimation task does not depend on the meaning of the values, but does depend on the selection of the empirically valued health states and the assumptions about the relationship between these values and the descriptive system.

Europe↗

PubMed1999

An economic evaluation of Tomudex (raltitrexed) and 5-fluorouracil plus leucovorin in advanced colorectal cancer.

Our objective was to establish the balance between costs and effects of treatment with Tomudex (raltitrexed) as an alternative to treatment with 5-fluorouracil (5-FU) plus leucovorin (LV) in patients with advanced colorectal cancer. Data were used from an international, open label randomized clinical trial. Costs were calculated by multiplying resource utilization data with Dutch estimates of unit costs. Effects have been expressed in terms of 6 months and 1 year survival, and in terms of the number of patients without severe adverse events including WHO grade 3 and 4 leucopenia, mucositis, anemia and severe asthenia. Cost effectiveness is expressed in terms of costs per additional day of survival and costs per additional patient without any severe adverse event. The clinical results did not show significant survival differences implying great uncertainty about the cost-effectiveness of raltitrexed in terms of additional costs per additional life-year gained. However, 80% of the initially higher cost of raltitrexed ($3132 per patient) is compensated by savings due to a more convenient administration scheme leading to a net cost of $626 per patient treated. Weighed against the decrease in adverse events, a cost-effectiveness ratio results of $3936 per additional patient free of any severe adverse event. More favorable estimates result when the convenience of the administration scheme is valued in positive monetary terms.

Antineoplastic Agents↗

PubMed1999

Impact of goal-oriented and model-based clinical pharmacokinetic dosing of aminoglycosides on clinical outcome: a cost-effectiveness analysis.

The benefits of a pharmacy-based, active therapeutic drug monitoring (TDM) service (ATM) on outcomes were examined in a prospective study at four hospitals. ATM involved pharmacokinetic dosage optimization at the start of treatment, subsequent Bayesian adaptive control, and frequent patient evaluation. Cost-effectiveness was calculated based on real costs. The ATM group comprised 105 patients and 127 patients with nonguided TDM who were followed up as controls. Forty-eight of the ATM and 62 of the nonguided TDM patients had an infection on admission. Peak concentrations in ATM patients were significantly higher (10.6+/-2.9 mg/L; nonguided TDM, 7.6+/-2.2 mg/L; p < 0.01). Trough levels in the ATM group were significantly lower (p < 0.01). There was a trend toward lower mortality in the ATM group (nine of 105 versus 18 of 127; p = 0.26) that was significant for patients with an infection on admission (one of the 48 ATM patients died versus nine of the 62 nonguided TDM patients; p = 0.023). ATM reduced the length of hospital stay for all patients in the study (20.0+/-1.4 days; nonguided TDM, 26.3+/-2.9 days; p = 0.045) and for patients admitted with an infection (12.6+/-0.8 days; nonguided TDM, 18.0+/-1.4; p < 0.001). The incidence of nephrotoxicity was reduced from 13.4% (nonguided TDM) to 2.9% (p < 0.01). With ATM, total costs were lower for all patients (Dutch guilders [DFL], 13,125+/-9,267; nonguided TDM, DFL 16,862+/-17,721; p < 0.05) and for patients admitted with an infection (DFL 8,883+/-3,778; nonguided TDM, DFL 11,743+/-7,437; p < 0.01). Goal-oriented, model-based dosing of aminoglycosides resulted in higher antibiotic efficacy, shorter hospitalization, and reduced incidence of nephrotoxicity. By combining efficacy with savings, ATM offered a significant alternative to usual care.

Aged↗

PubMed1998

[Guidelines and costs].

There is a growing interest in developing clinical guidelines which support the efficiency of medical care by weighting the potential benefits against the costs of interventions. In the recently developed Dutch guideline on reduction of serum cholesterol concentration a formal cost-effectiveness analysis is included. Based on epidemiological arguments a cost-effectiveness ratio of 40,000 Dutch guilders per life year gained was found. In comparison with other preventive health care programmes this amount was considered acceptable. In the past physicians have often taken costs into account in an implicit way when making clinical decisions. The results of the cost-effectiveness analysis vary particularly with the costs of the used statins. In the past physicians have often taken costs into account in an implicit way when making clinical decisions. However, in view of the increase in health care expenditures, it has become the responsibility of physicians to take costs into account more explicitly. Clinical guidelines with a cost-effectiveness analysis can be useful in helping physicians to provide efficient medical care.

Cost-Benefit Analysis↗

PubMed1998

[Economic evaluation of cardiology; background and application].

Effectiveness research is increasingly attracting the attention not only of policy makers but also of the medical profession. Economic evaluation may provide structured information about the cost-effect balance of an intervention as compared with that of a different intervention. Costs can be subdivided into direct and indirect medical costs and direct and indirect non-medical costs. Effects are preferably expressed in life years gained (corrected for quality). A cost-effectiveness ratio indicates the additional costs per additional life year gained (corrected for quality). Economic evaluation can be performed using local, national or international research data. It may use studies that have been completed or in which the economic evaluation is included. A (planned) subgroup analysis may help to define a group of patients for whom the cost-effectiveness ratio is most favourable. The duration of a randomized clinical trial is usually relatively brief; with the aid of a mathematical model it is possible to collect the available information and to calculate extrapolations for longer periods.

Cardiology↗

PubMed1998

Sample size calculation in economic evaluations.

A simulation method is presented for sample size calculation in economic evaluations. As input the method requires: the expected difference and variance of costs and effects, their correlation, the significance level (alpha) and the power of the testing method and the maximum acceptable ratio of incremental effectiveness to incremental costs. The method is illustrated with data from two trials. The first compares primary coronary angioplasty with streptokinase in the treatment of acute myocardial infarction, in the second trial, lansoprazole is compared with omeprazole in the treatment of reflux oesophagitis. These case studies show how the various parameters influence the sample size. Given the large number of parameters that have to be specified in advance, the lack of knowledge about costs and their standard deviation, and the difficulty of specifying the maximum acceptable ratio of incremental effectiveness to incremental costs, the conclusion of the study is that from a technical point of view it is possible to perform a sample size calculation for an economic evaluation, but one should wonder how useful it is.

2-Pyridinylmethylsulfinylbenzimidazoles↗

PubMed1998

Discounting costs and effects: a reconsideration.

Using a simple societal utility function--giving equal weight to current and future generations-it is concluded that costs need to be discounted on the basis of the expected increase in income and the marginal utility of consumption, and that effects need to be discounted on the basis of the expected increase in health and the marginal utility of health. It is derived that both rates need to be equal when assuming a kind of perfect market, where growth rates are determined by the societal utility function. It is argued that this is an extremely heroic assumption and that different discount rates may be needed. Additionally, the traditional 'inconsistency arguments' of Weinstein and Stason and of Keeler and Cretin are reconsidered. Within the context presented earlier, the first inconsistency only emerges when a growth equilibrium is assumed, reinforcing the arguments put forward before. The Keeler and Cretin paradox is reconsidered by showing that absolutely no paradox emerges when programs are not supposed to stop after a year but are supposed to continue indefinitely. The conclusion is drawn that non-believers in market mechanisms assuring an optimal social policy, need to reconsider the use of their discount rates.

Cost-Benefit Analysis↗

PubMed1998

Use of abciximab in interventional cardiology.

The advent of platelet membrane glycoprotein (GP) IIb/IIIa inhibitors has changed the landscape of interventional cardiology. Given the commercial availability of abciximab and expected regulatory approvals for other receptor blockers, defining appropriate use of these agents in the interventional setting is mandated. One key issue is selection of patients who may benefit from GP IIb/IIIa receptor blockade. Focusing specifically on abciximab, data from three large-scale, randomized trials demonstrate that abciximab is appropriate for all patients undergoing percutaneous transluminal coronary angioplasty, regardless of risk stratum. Other important issues to consider when prescribing this therapy include benefits in conjunction with stents and new devices, dosing and timing of administration, and the role of prophylactic versus "bailout" administration. This article reflects a distillation of the views and consensus regarding the use of GP IIb/IIIa inhibitors in patients undergoing coronary intervention expressed by a group of international experts convened in Davos, Switzerland, February 16, 1997. This report attempts to review clinical progress to date, formulate recommendations, and map out potentially fruitful lines of inquiry for future investigation.

Abciximab↗

PubMed1998

Costs and effects in therapy for acute coronary syndromes: the case of abciximab in high-risk patients undergoing percutaneous transluminal coronary angioplasty in the EPIC study. Evaluation of 7E3 for the Prevention of Ischemic Complications.

Cost-effectiveness analyses are routinely performed to determine whether the additional cost of a novel therapy is balanced by additional effectiveness. The definitions of costs and effects involve a variety of assumptions, both in general economic terms and with regard to the specific medical setting under consideration. Similarly, differing criteria for acceptability of cost-effectiveness estimates can be used to generate different conclusions regarding cost-effectiveness. The issues and problems inherent in economic evaluation are discussed by an analysis of findings with the platelet glycoprotein IIb/IIIa inhibitor abciximab in the EPIC (Evaluation of 7E3 for the Prevention of Ischemic Complications) study in high-risk patients undergoing percutaneous transluminal coronary angioplasty.

Abciximab↗

PubMed1998

Use of abciximab in interventional cardiology.

Abciximab↗

PubMed1998

Costs and effects in therapy for acute coronary syndromes: the case of abciximab in high-risk patients undergoing percutaneous transluminal coronary angioplasty in the EPIC study. Evaluation of 7E3 for the Prevention of Ischemic Complications.

Abciximab↗

PubMed1997

Bone density and risk of hip fracture in men and women: cross sectional analysis.

OBJECTIVE: To determine the relative contribution of decline in bone density to the increase in risk of hip fracture with age in men and women. DESIGN: Incidence data of hip fracture from the general population were combined with the bone density distribution in a sample from the same population and with a risk estimate of low bone density known from literature. SETTING: The Netherlands. SUBJECTS: All people with a hospital admission for a hip fracture in 1993, and bone density measured in a sample of 581.4 men and women aged 55 years and over in a district of Rotterdam. MAIN OUTCOME MEASURE: One year cumulative risk of hip fracture by age, sex, and bone density measured at the femoral neck. RESULTS: A quarter of all hip fractures occurred in men. Men reached the same incidence as women at five years older. Controlled for age, the risk of hip fracture by bone density was similar in men and women. The risk of hip fracture increased 13-fold from age 60 to 80; decrease in bone density associated with age contributed 1.9 (95% confidence interval 1.5 to 2.4) in women and 1.6 (1.3 to 1.8) in men. CONCLUSIONS: The risk of hip fracture by age and bone density is similar in men and women. The decrease in bone density associated with age makes a limited contribution to the exponential increase of the risk of hip fracture with age.

Age Factors↗