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Circulation. 2006;114:1745-1754
doi: 10.1161/CIRCULATIONAHA.106.646190
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(Circulation. 2006;114:1745-1754.)
© 2006 American Heart Association, Inc.


Controversies in Cardiovascular Medicine

Drug-Eluting Stents

The Price Is Not Right

Mark J. Eisenberg, MD, MPH

From the Divisions of Cardiology and Clinical Epidemiology, Jewish General Hospital/McGill University, Montreal, Quebec, Canada.

Correspondence to Mark J. Eisenberg, MD, MPH, Associate Professor of Medicine, Divisions of Cardiology and Clinical Epidemiology, Jewish General Hospital/McGill University, 3755 Cote Ste Catherine Rd, Suite A-118, Montreal, Quebec, Canada H3T 1E2. E-mail meisenberg{at}epid.jgh.mcgill.ca


*    Introduction
up arrowTop
*Introduction
down arrowClinical Effectiveness and DES...
down arrowCost-Effectiveness of DES Versus...
down arrowCost-Effectiveness Studies of...
down arrowCost-Effectiveness Studies of...
down arrowLimitations of DES Cost...
down arrowConclusions From DES Cost...
down arrowOther DES Cost Studies
down arrowCompeting Healthcare...
down arrowWhen Is DES Use...
down arrowEthical Considerations
down arrowConclusions
down arrowReferences
 

"Does it make economic sense to completely abandon a therapy that works well for 85% to 90% of the population for a new therapy costing four times as much to treat a transient health condition with no impact on either death or myocardial infarction?"

J.M. Brophy and L.J. Erickson1

Since Andreas Gruntzig performed the first percutaneous coronary intervention (PCI) in 1977,2 the cost-effectiveness of this procedure has engendered major controversy. Debates have erupted over the clinical value and cost-effectiveness of each new device or therapy that has become available. Controversies have arisen regarding the cost of atherectomy, bare metal stents (BMS), brachytherapy, distal protection devices, glycoprotein IIb/IIIa inhibitors, and intravascular ultrasound.3–6 Drug-eluting stents (DES) are the most recent devices to have their cost scrutinized.7–12

Response by Ryan and Cohen p 1754


*    Clinical Effectiveness and DES Penetration
up arrowTop
up arrowIntroduction
*Clinical Effectiveness and DES...
down arrowCost-Effectiveness of DES Versus...
down arrowCost-Effectiveness Studies of...
down arrowCost-Effectiveness Studies of...
down arrowLimitations of DES Cost...
down arrowConclusions From DES Cost...
down arrowOther DES Cost Studies
down arrowCompeting Healthcare...
down arrowWhen Is DES Use...
down arrowEthical Considerations
down arrowConclusions
down arrowReferences
 
Balloon angioplasty is associated with restenosis rates of 30% to 40%, whereas PCI with BMS is associated with rates of 20% to 30%,13,14 and PCI with DES is associated with rates in the single digits.15,16 My colleagues and I pooled the results of 11 DES trials involving >5000 patients using a hierarchical Bayesian random-effects model.17 We found that, compared with BMS, DES reduce angiographic restenosis from 29.3% to 8.9% (Table 1 and Figure 1). There was no difference between DES and BMS in terms of mortality (0.9% versus 0.9%, respectively) or myocardial infarction (2.7% versus 2.9%, respectively). There was a suggestion that restenosis was less with sirolimus-eluting stents (SES) compared with polymeric paclitaxel-eluting stents (PES) (6.2% for SES versus 36.9% for BMS; 7.1% for PES versus 23.5% for BMS), a finding that was subsequently identified in another meta-analysis.18


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TABLE 1. Clinical Events and Restenosis Rates in Randomized Clinical Trials Investigating DESs


Figure 1178620
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Figure 1. Forest plot comparing rates of angiographic restenosis for DES and BMS. Reproduced from Babapulle et al17 with permission from Elsevier. Copyright 2004.

The interventional community quickly embraced the results of the DES trials. DES use has become nearly ubiquitous in the United States,19 and its use is becoming widespread outside the United States as well. Rather than reserving this high-cost technology for patients who are at high risk for restenosis, many interventional cardiologists are placing these stents in all patients, including those whose baseline risk of restenosis is low. Before the universal use of DES becomes an entrenched practice, we need to know the answer to the following question: Is the clinical benefit associated with DES substantial enough to justify the use of this high-cost technology in all patients undergoing PCI? Several lines of evidence suggest that DES are currently too expensive to be used in an across-the-board manner in all patients undergoing PCI. These data come from a variety of studies comparing the cost-effectiveness of DES and BMS that have been performed in various countries.


*    Cost-Effectiveness of DES Versus BMS
up arrowTop
up arrowIntroduction
up arrowClinical Effectiveness and DES...
*Cost-Effectiveness of DES Versus...
down arrowCost-Effectiveness Studies of...
down arrowCost-Effectiveness Studies of...
down arrowLimitations of DES Cost...
down arrowConclusions From DES Cost...
down arrowOther DES Cost Studies
down arrowCompeting Healthcare...
down arrowWhen Is DES Use...
down arrowEthical Considerations
down arrowConclusions
down arrowReferences
 
A PubMed search for studies comparing the cost-effectiveness of DES versus BMS identified 7 studies from North America (Table 2)20–26 and 6 studies from Australia and Europe (Table 3).27–32 Only studies that reported cost per quality-adjusted life-year (QALY) gained or cost per repeat revascularization avoided were included. Cost per QALY gained is the primary outcome measure of most cost-effectiveness analyses. Using this measure, we can directly compare the cost-effectiveness of different healthcare interventions (Table 4).33 In the United States, an intervention associated with a cost per QALY gained of <$50 000 is considered to be cost-effective; one associated with a cost per QALY gained of $50 000 to $100 000 is in the "gray area"; and one associated with a cost per QALY gained of >$100 000 is considered unattractive.34 Cost per repeat revascularization avoided is the other measure that is commonly used in DES cost-effectiveness studies. This disease-specific measure allows us to examine whether the incremental cost of DES above that of BMS is offset by the cost savings brought about by a reduction in the need for subsequent revascularization procedures. In the United States, a cost per revascularization avoided <$10 000 is thought to be cost-effective.20,21


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TABLE 2. Cost-Effectiveness Studies of DES in North America


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TABLE 3. Cost-Effectiveness Studies of DES in Australia and Europe


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TABLE 4. Cost-Effectiveness and Use of Selected Interventions in the Medicare Population*


*    Cost-Effectiveness Studies of DES in the United States
up arrowTop
up arrowIntroduction
up arrowClinical Effectiveness and DES...
up arrowCost-Effectiveness of DES Versus...
*Cost-Effectiveness Studies of...
down arrowCost-Effectiveness Studies of...
down arrowLimitations of DES Cost...
down arrowConclusions From DES Cost...
down arrowOther DES Cost Studies
down arrowCompeting Healthcare...
down arrowWhen Is DES Use...
down arrowEthical Considerations
down arrowConclusions
down arrowReferences
 
At the time of this writing, only 2 traditional cost-effectiveness studies examining DES in the context of the United States have been published; both are from the same group at the Harvard Clinical Research Institute (Table 2).20,21 Despite these surprisingly limited cost-effectiveness data, DES are being used in the vast majority of PCI procedures now being performed in the United States.19

Greenberg et al20 published a review of the economic impact of restenosis and DES. Embedded within the review was a decision-analytic model examining DES cost-effectiveness. The model used outcome and resource use data from >6000 "real-world" patients undergoing single-vessel PCI procedures.35–37 Costs were based on pooled data from several clinical trials involving >3000 patients. The model used the following assumptions: (1) a BMS repeat revascularization rate of 14%, (2) an 80% reduction in repeat revascularization rates with DES, (3) an incremental cost of $2000 per DES, and (4) a mean use of 1.3 stents per PCI. Over a 2-year follow-up, this model indicated that overall medical care costs are approximately $900 per patient higher with DES than with BMS, with an incremental cost-effectiveness ratio of approximately $7000 per repeat revascularization avoided. Sensitivity analyses suggested that treatment with DES is cost saving for patients with a BMS repeat revascularization rate >20% and cost-effective (<$10 000 per repeat revascularization avoided) for patients with a BMS repeat revascularization rate >12% (Figure 2). The authors concluded that, compared with BMS, DES are cost saving for only a modest proportion of the current PCI population in the United States. However, they did suggest that DES are economically attractive for virtually all diabetic patients and for nondiabetic patients with small vessels and long lesions. Greenberg et al did not report a cost per QALY gained, but they concluded that the cost-effectiveness of DES is dependent on the target population undergoing PCI and the alternative therapy that might be used (ie, medical therapy, BMS, or coronary artery bypass grafting.


Figure 2178620
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Figure 2. Relationship between the rate of target vessel revascularization with BMS implantation and the incremental cost-effectiveness of DES implantation for patients undergoing single-vessel PCI. Reproduced from Greenberg et al20 with permission from the American College of Cardiology Foundation. Copyright 2004.

Cohen et al21 reported an economic analysis of the SIRIUS trial.2 Clinical outcomes, resource use, and costs were prospectively collected for 1058 patients who received either an SES or a BMS over a 1-year period. Initial hospital costs were increased by $2881 per patient with DES. During the 1-year follow-up, use of DES versus BMS was associated with reductions in the rates of repeat PCI (12.4% versus 26.9%, respectively) and bypass surgery (1.3% versus 3.0%, respectively). Although follow-up costs were reduced by $2571 per patient with DES, aggregate 1-year costs were still $309 per patient higher. The incremental cost-effectiveness ratios for DES were $27 540 per QALY gained and $1650 per repeat revascularization avoided. The authors concluded that, although the use of SES was not cost saving compared with BMS, for patients undergoing PCI of complex coronary lesions, the use of DES appeared to be reasonably cost-effective within the context of the United States healthcare system.

These 2 studies examining the cost-effectiveness of DES in the context of the United States came to similar conclusions. Both studies suggested that DES are cost-effective in high-risk patients with respect to repeat revascularizations avoided. In addition, although the study by Greenberg et al20 did not report a cost per QALY gained, the figure reported by Cohen et al21 falls within the range that is generally accepted as being cost-effective in the United States (<$50 000 per QALY gained) (Table 4). However, the conclusions drawn from these 2 studies must be tempered in view of the assumptions and methodologies used.

Greenberg et al20 assumed that all patients underwent single-vessel PCI with a mean use of 1.3 DES per procedure. In contrast, other cost-effectiveness studies assumed a mean use of 1.5 DES per PCI; some have even used 1.7 or 1.9 (Tables 2 and 3Up). Minimizing the number of DES used per PCI minimizes the estimated cost per repeat revascularization avoided. In addition, because DES allow us to treat more complex lesions than were treated previously, it is likely that future PCI procedures will use more rather than fewer stents per case.

Cohen et al21 performed a textbook-perfect cost-effectiveness study as part of the SIRIUS trial. However, the results of this study were affected by the use of protocol-mandated angiography. Most of the DES trials, including the SIRIUS trial, used protocol-mandated follow-up angiography at 6 to 9 months with subsequent clinical follow-up several months later. Because follow-up angiography was performed in all patients, many cases of angiographic restenosis were identified in patients who were asymptomatic. If restenosis was identified at the time of the protocol-mandated angiography, repeat PCI was frequently performed—often called the oculostenotic reflex. These asymptomatic patients who had angiographic but not clinical restenosis were then identified as achieving one of the predefined end points of the trial: need for repeat revascularization. The effect of protocol-mandated angiography can be seen in the Kaplan-Meier survival curves for the RAndomized study with the sirolimus-eluting Bx VELocity balloon-expandable stent (Cypher; RAVEL) trial (Figure 3).38 At the time of the mandated angiographic follow-up, there was a sharp rise in the identification of restenosis and occurrence of repeat revascularization procedures. Repeat revascularization in the BMS group jumped from 6% before angiography to >20% after angiography. Similar increases were seen in other DES trials that used protocol-mandated angiography (Table 5).28,39–41 Although Cohen et al tried to account for the use of protocol-mandated angiography in their analysis, they were overly optimistic in both the clinical effectiveness data that they used in their cost analysis and the subsequent DES cost-effectiveness that they reported.


Figure 3178620
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Figure 3. Kaplan-Meier estimates of survival free of myocardial infarction and repeated revascularization among patients who received SES and those who received BMS in the RAVEL trial. The percent of event-free patients in the BMS group decreased rapidly during the period of angiographic follow-up. This decrease was due to an increase in restenosis and subsequent target lesion revascularizations identified by the angiographic follow-up. Adapted and reproduced from Morice et al with permission from the Massachusetts Medical Society. Copyright 2002.


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TABLE 5. Target Lesion Revascularization Rates With BMS in DES Trials Before and After Protocol-Mandated Angiography


*    Cost-Effectiveness Studies of DES Outside the United States
up arrowTop
up arrowIntroduction
up arrowClinical Effectiveness and DES...
up arrowCost-Effectiveness of DES Versus...
up arrowCost-Effectiveness Studies of...
*Cost-Effectiveness Studies of...
down arrowLimitations of DES Cost...
down arrowConclusions From DES Cost...
down arrowOther DES Cost Studies
down arrowCompeting Healthcare...
down arrowWhen Is DES Use...
down arrowEthical Considerations
down arrowConclusions
down arrowReferences
 
In contrast to the 2 published studies from the United States, 5 studies from Canada suggest that across-the-board use of DES in all PCI patients is not cost-effective. Although the Canadian dollar is worth {approx}90 cents American at the time of this writing, the thresholds considered to be cost-effective in Canada are somewhat different than those in the United States. The reason for this is that the costs of repeat PCI and coronary artery bypass grafting are much less in Canada.42 Cost-effectiveness thresholds in Canada are <Can $50 000 per QALY gained and <Can $12 551 per repeat revascularization avoided.26

Bowen et al22 performed a cost-effectiveness analysis of DES for the Ontario Ministry of Health and Long-Term Care. These investigators found that DES were associated with an exceedingly high cost per QALY gained: Can $438 415 to Can $2 221 692, ratios that clearly place this technology in the non–cost-effective range. In addition, the cost per revascularization avoided was also prohibitive: from Can $17 711 for patients with a recent myocardial infarction and diabetes to Can $95 383 for patients without a myocardial infarction or diabetes.

Shrive et al23 performed a cost-effectiveness analysis of SES on behalf of the Alberta Provincial Project for Outcome Assessment in Coronary Heart Disease (APPROACH) investigators. They found that SES use was associated with a cost per QALY gained of Can $58 721 and that SES use was more cost-effective in patients with diabetes and in those >75 years of age (Can $44 135 and Can $40 129 per QALY gained, respectively). For patients <65 years of age and those without diabetes, SES use was substantially less cost-effective (Can $72 464 and Can $63 383 per QALY gained, respectively).

Mittmann et al24 performed a cost-effectiveness analysis of DES for the Canadian Coordinating Office for Health Technology Assessment. The investigators found that PES use was associated with a cost per revascularization avoided of Can $26 562 to Can $29 048, whereas SES use was associated with a cost of Can $12 527 to Can $16 600. The investigators did not calculate costs per QALY gained. However, they did examine the impact of DES use on the annual Canadian healthcare budget. They found that extending DES use from the 40% of patients at highest risk for restenosis to 100% of patients undergoing PCI would lead to a >3-fold increase in DES costs but only a 1.5-fold reduction in repeat revascularization procedures.

Brophy and Erickson25 performed a cost-effectiveness analysis of DES for the Quebec Agency for the Evaluation of Technology and Health Interventions. The investigators calculated that cost per revascularization avoided would increase from Can $7000 at 20% DES penetration to Can $23 067 at 100% DES penetration. The investigators also calculated the price at which DES use would be cost neutral assuming different DES penetration rates. With a 20% use in patients at highest risk, the break-even cost for DES would be Can $1663; at 60%, it would be Can $1266; and at 100%, it would be Can $1161.

Rinfret et al26 investigated the cost-effectiveness of SES versus BMS in high-risk patients with single long de novo lesions in small coronary arteries. These investigations found that BMS use versus balloon angioplasty is associated with a cost per repeat revascularization avoided of Can $12 551 and that SES versus BMS use was associated with a cost per repeat revascularization avoided of Can $11 275. The investigators concluded that DES are borderline cost-effective in Canada in a high-risk subgroup of patients.

Thus, 5 cost-effectiveness studies from Canada suggest that DES are not an attractive therapy to be used in an across-the-board manner. The authors of each of these studies suggested that, at current prices, DES are too expensive to be cost-effective except in selected groups of high-risk patients.

Authors of DES cost-effectiveness studies in Australia, Sweden, Switzerland, and the United Kingdom all reported results similar to those found in Canada (Table 3). Importantly, the BAsel Stent Kosten Effektivitäts Trial (BASKET) investigators prospectively performed a study in which they examined the cost-effectiveness of DES in a group of patients randomized to DES or BMS.30 As opposed to most other studies, costs were prospectively collected, and patients did not undergo protocol-mandated follow-up angiography. A total of 826 patients were randomized to SES, PES, or BMS. The aggregate costs at 6 months were higher with DES than with BMS, and higher stent costs were not compensated for by lower follow-up costs (overall 6-month costs were still 905 Formula higher in the DES group). The incremental cost-effectiveness ratio to avoid 1 major adverse cardiac event was 18 311 Formula , and the cost per QALY gained was more than 50 000 Formula . The authors concluded that, in a real-world setting, use of DES should be restricted to patients in high-risk groups. Importantly, BASKET also suggested that DES are associated with a significantly higher rate of thrombotic complications compared with BMS during the 6 months following the cessation of clopidogrel.43 Therefore, the need for prolonged treatment with clopidogrel will further reduce the cost-effectiveness of DES.


*    Limitations of DES Cost-Effectiveness Studies
up arrowTop
up arrowIntroduction
up arrowClinical Effectiveness and DES...
up arrowCost-Effectiveness of DES Versus...
up arrowCost-Effectiveness Studies of...
up arrowCost-Effectiveness Studies of...
*Limitations of DES Cost...
down arrowConclusions From DES Cost...
down arrowOther DES Cost Studies
down arrowCompeting Healthcare...
down arrowWhen Is DES Use...
down arrowEthical Considerations
down arrowConclusions
down arrowReferences
 
Despite the fact that most studies have not found DES to be cost-effective in an across-the-board manner, many of these studies still painted an overly optimistic picture of the cost-effectiveness of DES. Two limitations of these studies were responsible. First, the true cost of DES procedures was underestimated; second, the clinical effectiveness of DES was overestimated.

Although the cost of a single DES is reasonably well established, the published studies used a mean number of stents per PCI between 1.0 and 1.9. The assumption of a lower number of stents per PCI leads to a better cost-effectiveness ratio; the assumption of a higher number leads to a worse cost-effectiveness ratio. With the advent of DES, there has been a trend of performing increasingly complex PCI procedures. This trend will likely lead to an even greater number of stents per patient in the future. Thus, previous studies underestimated the true cost of DES procedures, and this led to an overly optimistic view of DES cost-effectiveness.

Previous studies also overestimated the clinical effectiveness of DES. Most of these studies based their calculations on data obtained from previous DES trials. Unfortunately, most of these trials enrolled patients with solitary de novo coronary lesions and used protocol-mandated angiography. These features led to the observations of low restenosis rates in patients receiving DES and high rates of restenosis and repeat revascularization procedures in patients receiving BMS. The use of inflated estimates of clinical effectiveness led to overly optimistic estimates of DES cost-effectiveness. Studies like the BASKET trial that were performed in real-world settings without the use of protocol-mandated angiography found that the clinical benefit of DES is substantially less than that described in randomized controlled trials. Consequently, the cost-effectiveness studies that relied on the early DES trials were overly optimistic in the clinical effectiveness data that they used.


*    Conclusions From DES Cost-Effectiveness Studies
up arrowTop
up arrowIntroduction
up arrowClinical Effectiveness and DES...
up arrowCost-Effectiveness of DES Versus...
up arrowCost-Effectiveness Studies of...
up arrowCost-Effectiveness Studies of...
up arrowLimitations of DES Cost...
*Conclusions From DES Cost...
down arrowOther DES Cost Studies
down arrowCompeting Healthcare...
down arrowWhen Is DES Use...
down arrowEthical Considerations
down arrowConclusions
down arrowReferences
 
Despite their limitations, several important conclusions can be derived from the DES cost-effectiveness studies that have been published. First, DES are not cost saving and they are not cost neutral. A substantial amount of money has to be spent to obtain a modest clinical benefit. Second, if DES are used in place of BMS, some but not all of the initial cost is recouped during the follow-up period as a result of a reduced need for repeat revascularization procedures. Third, because DES have no impact on mortality or myocardial infarction rates and because their effect on quality of life is modest, DES are associated with a high cost per QALY gained. Thus, the sole justification for the use of DES is their ability to reduce the need for repeat revascularization procedures. If these procedures are expensive, the incremental cost-effectiveness ratios associated with DES are attractive; if these procedures are inexpensive, the incremental cost-effectiveness ratios are unattractive. Finally, the cost-effectiveness of DES can be markedly enhanced by either decreasing their price or reserving their use for patients who are at high risk for restenosis. At current prices, using DES in an across-the-board manner is not an optimal strategy from a cost-effectiveness point of view.


*    Other DES Cost Studies
up arrowTop
up arrowIntroduction
up arrowClinical Effectiveness and DES...
up arrowCost-Effectiveness of DES Versus...
up arrowCost-Effectiveness Studies of...
up arrowCost-Effectiveness Studies of...
up arrowLimitations of DES Cost...
up arrowConclusions From DES Cost...
*Other DES Cost Studies
down arrowCompeting Healthcare...
down arrowWhen Is DES Use...
down arrowEthical Considerations
down arrowConclusions
down arrowReferences
 
Besides the traditional cost-effectiveness studies detailed above, a number of studies have examined the economics of DES from other perspectives. Several studies examined the decline in DES price required for DES to be cost neutral (the break-even price).44,45 Several studies examined the impact of DES penetration on hospital budgets,46,47 and other studies examined the impact of DES on global healthcare budgets.48–51 The conclusions from these studies can be summarized as follows. First, DES prices have to decline substantially before break-even prices are reached. Second, from both hospital and societal perspectives, across-the-board use of DES leads to substantial increases in budgetary costs that are not recouped by a reduced need for subsequent revascularization procedures.


*    Competing Healthcare Interventions
up arrowTop
up arrowIntroduction
up arrowClinical Effectiveness and DES...
up arrowCost-Effectiveness of DES Versus...
up arrowCost-Effectiveness Studies of...
up arrowCost-Effectiveness Studies of...
up arrowLimitations of DES Cost...
up arrowConclusions From DES Cost...
up arrowOther DES Cost Studies
*Competing Healthcare...
down arrowWhen Is DES Use...
down arrowEthical Considerations
down arrowConclusions
down arrowReferences
 
Another issue should be considered before deciding on a policy to guide our use of DES. Even in affluent societies, resources available for healthcare interventions are not unlimited.48 In reality, multiple potential healthcare interventions are in competition for the same resources; consequently, some interventions receive funding while others do not. The best way to determine which interventions will be funded is not by individual studies of cost-effectiveness but instead by directly contrasting the cost-effectiveness ratios of alternative interventions. Many healthcare interventions are associated with a cost per QALY gained in the gray area of $50 000 to $100 000. If we funded each of these interventions, we would quickly deplete the budget of every hospital and every healthcare system. The most efficient, and perhaps the most equitable, way of using our limited healthcare resources is by reimbursing for the most cost-effective interventions. Our budget should first be spent on the most cost-effective intervention, followed by the second most cost-effective intervention, and so on until our resources are spent. In this fashion, the most health benefit is obtained for a given amount of limited resources. The current method of comparing healthcare interventions in isolation leads to inequities. Many high-cost but low-yield interventions are currently available, but other low-cost but high-yield interventions are not. With this perspective in mind, an across-the-board use of DES cannot be justified.


*    When Is DES Use Cost-Effective?
up arrowTop
up arrowIntroduction
up arrowClinical Effectiveness and DES...
up arrowCost-Effectiveness of DES Versus...
up arrowCost-Effectiveness Studies of...
up arrowCost-Effectiveness Studies of...
up arrowLimitations of DES Cost...
up arrowConclusions From DES Cost...
up arrowOther DES Cost Studies
up arrowCompeting Healthcare...
*When Is DES Use...
down arrowEthical Considerations
down arrowConclusions
down arrowReferences
 
Although DES are not cost-effective in an across-the-board manner, at current prices, DES may well be cost-effective in several subgroups of high-risk patients. These subgroups include patients at high risk for restenosis (eg, diabetics and those with long lesions and small vessels) (Table 6)37 and patients who would otherwise undergo coronary artery bypass surgery. Other subgroups in which DES may prove to be cost-effective include patients with left main lesions, patients with proximal left anterior descending artery lesions, patients with lesions in saphenous vein grafts, and patients with complex lesions who are at high risk for restenosis. However, at this time, few cost-effectiveness data have been derived directly from these high-risk subgroups. The data that are available are mostly extrapolated rather than directly measured. The cost-effectiveness of DES in these high-risk subgroups should be closely explored before the routine use of DES in these patients becomes entrenched.


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TABLE 6. Predicted Rates of Clinical Restenosis After BMS Implantation as a Function of Lesion Length, Reference Vessel Diameter, and Diabetes


*    Ethical Considerations
up arrowTop
up arrowIntroduction
up arrowClinical Effectiveness and DES...
up arrowCost-Effectiveness of DES Versus...
up arrowCost-Effectiveness Studies of...
up arrowCost-Effectiveness Studies of...
up arrowLimitations of DES Cost...
up arrowConclusions From DES Cost...
up arrowOther DES Cost Studies
up arrowCompeting Healthcare...
up arrowWhen Is DES Use...
*Ethical Considerations
down arrowConclusions
down arrowReferences
 
If DES are used in an across-the-board manner in all PCI patients, well over half of the patients who receive these stents will not derive any clinical benefit from them. One has to question whether it is ethical to subject large numbers of patients who are at low risk of restenosis to the small but real risk of late thrombosis known to be associated with DES.52–54 Moreover, the widespread use of DES and the ensuing risk of late thrombosis is creating a new clinical phenomenon: long-term dependence on clopidogrel. With an aging population and with the increased bleeding risks associated with clopidogrel, we may need to temper our enthusiasm regarding DES. One also has to question whether it is ethical to use an extremely high-cost technology in many patients who will not derive any clinical benefit while denying more essential health care to many patients who do not have the financial resources to pay for it. Although framing the issue in this manner may not be popular, policy makers in many countries have decided that using BMS in patients at low risk of restenosis will free up valuable resources that can be used to improve health care in other arenas. With an increasing realization that limited healthcare resources must be used in an optimal manner, a healthy debate about the ethics of using DES at their current prices in an across-the-board manner should be encouraged.


*    Conclusions
up arrowTop
up arrowIntroduction
up arrowClinical Effectiveness and DES...
up arrowCost-Effectiveness of DES Versus...
up arrowCost-Effectiveness Studies of...
up arrowCost-Effectiveness Studies of...
up arrowLimitations of DES Cost...
up arrowConclusions From DES Cost...
up arrowOther DES Cost Studies
up arrowCompeting Healthcare...
up arrowWhen Is DES Use...
up arrowEthical Considerations
*Conclusions
down arrowReferences
 
Almost 30 years after Andreas Gruntzig performed the first PCI, the debate about the cost-effectiveness of this procedure still arouses controversy. Interventional cardiology is a constantly changing field, and new devices and therapies are continually being introduced. Some of these devices and therapies find a permanent place; others are eventually discarded. After the initial cost-effectiveness debates, virtually all of these devices and therapies drop in price until the cost-effectiveness debates are scarcely remembered. I anticipate that a similar scenario will occur with DES. As second- and third-generation DES become available and as new companies enter the market, prices will drop. In addition, improvements in stent design, use of different polymers, and the introduction of cheaper and more effective drugs that can be eluted from stents will lead to an increase in DES effectiveness. As prices drop and clinical effectiveness increases, the cost-effectiveness of DES will improve substantially. Our original question was, Is the clinical benefit associated with DES substantial enough to justify the use of this high-cost technology in all patients undergoing PCI? I think that the cost-effectiveness data that we now have available indicate that DES are currently too expensive to be used in all patients undergoing PCI. However, as their prices drop and as their effectiveness increases, DES will become increasingly attractive from a cost-effectiveness point of view, and their use will likely become a permanent addition to the pantheon of interventional cardiology.


*    Acknowledgments
 
The author would like to thank Robert Sowerby for his expert assistance in the preparation of the tables and Dr Stephane Rinfret for his critical review of the manuscript.

Sources of Funding

Dr Eisenberg is a Senior Physician-Scientist of the Quebec Foundation for Health Research.

Disclosures

None.


*    References
up arrowTop
up arrowIntroduction
up arrowClinical Effectiveness and DES...
up arrowCost-Effectiveness of DES Versus...
up arrowCost-Effectiveness Studies of...
up arrowCost-Effectiveness Studies of...
up arrowLimitations of DES Cost...
up arrowConclusions From DES Cost...
up arrowOther DES Cost Studies
up arrowCompeting Healthcare...
up arrowWhen Is DES Use...
up arrowEthical Considerations
up arrowConclusions
*References
 
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2. Gruntzig AR, Senning A, Siegenthaler WE. Nonoperative dilatation of coronary-artery stenosis: percutaneous transluminal coronary angioplasty. N Engl J Med. 1979; 301: 61–68.[Abstract]

3. Weintraub WS. Economics of coronary stenting and GP IIb/IIIa blockade. Eur Heart J. 2001; 22: 1366–1368.[Free Full Text]

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Response to Eisenberg

Jason Ryan, MD, MPH; David J. Cohen, MD, MSc

In this issue of Circulation, we and Dr Eisenberg have reviewed the data on the economic impact of drug-eluting stents (DES) and come to seemingly opposite conclusions. In this debate, as in many others, however, the true value lies not in the conclusions themselves but in exploring the reasons for these alternative views. In the case of the DES controversy, 2 fundamental differences largely explain our divergent conclusions. The first is regarding the principle that cost-effectiveness always reflects an incremental analysis. In other words, a device or procedure cannot be evaluated in a vacuum but rather must be compared with an alternative treatment strategy. Taken to its logical conclusion, this concept implies that economic analyses should be focused on specific patient subgroups (based on any number of potential patient characteristics), within the bounds of evidence to distinguish differences in cost and clinical effectiveness. This concept of incremental analysis is the basis for Dr Eisenberg’s assertion that conclusions about cost-effectiveness of DES based on clinical trials reflect only the specific population under investigation. We wholeheartedly agree with this point and acknowledge that this is an important limitation of virtually all trial-based economic evaluations. In an ideal world, it would be most efficient to allocate DES specifically to those patients for whom they are most cost-effective and to withhold them from patients who derive only marginal benefit. Unfortunately, at present, the healthcare reimbursement systems in most countries are not sufficiently sophisticated to accommodate this level of analysis. Indeed, decisions about reimbursement for new medical technologies rarely differentiate between populations that derive different levels of absolute benefit (and, as a result, different cost-effectiveness levels). This contrast between optimal resource allocation at the individual level versus at the population level is 1 of the key differences between Dr Eisenberg’s view and our own. The second key difference between our position and that of Dr Eisenberg is the perspective of the analysis. Virtually all of the data we cite are based on studies conducted within the United States, whereas most of the analyses cited by Dr Eisenberg are derived from studies conducted in other countries such as Canada and Switzerland. In addition to different care patterns, these countries tend to have lower costs for procedures and hospitalizations and spend far less on health care than in the United States, and these factors would tend to minimize the economic benefit of DES. In the case of the debate on DES versus bare metal stents, differences in the country chosen for the analysis may be at least as important as the underlying patient population. In light of these considerations, we believe that there is more agreement than disagreement in this debate. There is little question that DES are more cost-effective for patients at higher risk of restenosis than for patients for whom the restenosis risk is relatively low. Optimal application of DES technology would certainly focus on those patients for whom it is highly cost-effective. Given the realities of our current reimbursement system, however, it seems unlikely that such fine gradations can be reliably enforced. Therefore, if one accepts the concept that DES should be evaluated in aggregate, we believe that the data are clear. At least from the standpoint of the US healthcare system, the balance of costs and benefits currently favors DES implantation for the overall percutaneous coronary intervention population. Given the numerous differences in practice patterns, treatment costs, and cost-effectiveness thresholds, however, it is clear that this conclusion cannot be readily extrapolated to other countries and healthcare systems and that additional population-based analyses are needed.


*    Footnotes
 
The opinions expressed in this article are not necessarily those of the editors or of the American Heart Association.




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