Cost-effectiveness analyses of drug eluting stents versus bare metal stents: A systematic review of the literature

The cost-effectiveness of guideline-driven use of drug-eluting stents: propensity-score matched analysis of a seven-year multicentre experience

Background: In routine clinical practice, the implantation of a drug-eluting stent (DES) versus a bare metal stent (BMS) for percutaneous coronary intervention (PCI) has been guided by criteria for appropriate use. The cost-effectiveness (CE) of adopting these guidelines, however, is not clear, and was investigated from the perspective of the Australian healthcare payer.Methods and results: Baseline and 12-month follow-up data of 12,710 PCI patients enrolled in the Melbourne Interventional Group (MIG) registry between 2004 and 2011 were analysed. Costs inputs were derived from a clinical costing database and published sources. Propensity-score-matching was performed for DES and BMS groups within sub-groups. Incremental cost-effectiveness ratios (ICERs) were evaluated for all patients, and sub-groups of patients with '0', 1, 2, or ≥3 indications for a DES. The incremental cost per target vessel revascularization avoided for the overall population was $24,683, and for patients with 0, 1, and 2 indications for a DES was $44,635, $33,335, and $23,788, respectively. However, for those with >3 indications, DES compared with BMS was associated with cost savings. At willingness to pay thresholds of $45,000-$75,000, the probability of cost-effectiveness of DES for the overall cohort was 71-91%, '0' indications, 49-67%, 1 indication, 56-82%, 2 indications, 70-90%, and ≥3 indications, 97-99%.Conclusions: The cost-effectiveness of DES compared with BMS increased with increasing risk profile of patients from those who had 1, 2, to ≥3 indications for a DES. When compared with BMS, DES was least cost effective among patients with '0' indications for a DES. Based on these results, selective use of DES implantation is supported. These findings may be useful for evidence-based clinical decision-making.

A systematic review of cost-effectiveness of percutaneous coronary intervention vs. surgery for the treatment of multivessel coronary artery disease in the drug-eluting stent era

Aims

The suitability of percutaneous coronary intervention (PCI), compared with coronary artery bypass grafting (CABG), for patients with complex multivessel coronary artery disease (MVCAD) remains a contentious topic. While the body of evidence regarding the clinical effectiveness of these revascularization strategies is growing, there is limited evidence concerning their long-term cost-effectiveness. We aim to critically appraise the body of literature investigating the cost-effectiveness of CABG compared with PCI using stents, and to assess the quality of the economic evidence available.

Methods and results

A systematic review was performed across six electronic databases; Medline, Embase, the NHS Economic Evaluation Database, the Database of Abstracts of Reviews of Effects, the health technology assessment database, and the Cochrane Library. All studies comparing economic attractiveness of CABG vs. PCI using bare-metal stents (BMS) or drug-eluting stents (DES) in balanced groups of patients were considered. Sixteen studies were included. These comprised studies of conventional CABG vs. BMS (n = 8), or DES (n = 4); off-pump CABG vs. BMS (n = 2), or DES (n = 1); and minimally invasive direct CABG vs. BMS (n = 2). The majority adopted a healthcare payer perspective (n = 14). The incremental cost-effectiveness ratios (ICERs) reported across studies varied widely according to perspective and time horizon. Favourable lifetime ICERs were reported for CABG in three trials. For patients with left main coronary artery disease, however, DES was reported as the dominant (more effective and cost-saving) strategy in one study.

Conclusion

Overall, CABG rather than PCI was the favoured cost-effective treatment for complex MVCAD in the long term. While the evidence base for the cost-effectiveness of DES compared with CABG is growing, there is a need for more evaluations adopting a societal perspective, and time horizons of a lifetime or 10 or more years.

A systematic review and critical analysis of cost-effectiveness studies for coronary artery disease treatment

Background: Cardiovascular disease remains the primary cause of death among Australians, despite dramatic improvements in overall cardiovascular health since the 1980s. Treating cardiovascular disease continues to place a significant economic strain on the Australian health care system, with direct healthcare costs exceeding those of any other disease. Coronary artery disease accounts for nearly one third of these costs and spending continues to rise. A range of treatments is available for coronary artery disease yet evidence of cost-effectiveness is missing, particularly for the Australian context. Cost-effectiveness evidence can signal waste and inefficiency and so is essential for an efficient allocation of healthcare resources. Methods: We used systematic review methods to search the literature across several electronic databases for economic evaluations of treatments for coronary artery disease.  We critically appraised the literature found in searches, both against the CHEERS statement for quality reporting of economic evaluations and in terms of its usefulness for policy and decision-makers. Results: We retrieved a total of 308 references, 229 once duplicates were removed. Of these, 26 were excluded as they were not full papers (letters, editorials etc.), 55 were review papers, 50 were not cost-effectiveness analyses and 93 related to a highly specific patient sub-group or did not consider all treatment options.  This left five papers to be reviewed in full. Conclusions: The current cost-effectiveness evidence does not support the increased use of PCI that has been seen in Australia and internationally. Due to problems with accessibility, clarity and relevance to policy and decision-makers, some otherwise very scientifically rigorous analyses have failed to generate any policy changes.

A systematic review and critical analysis of cost-effectiveness studies for coronary artery disease treatment

Background: Cardiovascular disease remains the primary cause of death among Australians, despite dramatic improvements in overall cardiovascular health since the 1980s. Treating cardiovascular disease continues to place a significant economic strain on the Australian health care system, with direct healthcare costs exceeding those of any other disease. Coronary artery disease accounts for nearly one third of these costs and spending continues to rise. A range of treatments is available for coronary artery disease yet evidence of cost-effectiveness is missing, particularly for the Australian context. Cost-effectiveness evidence can signal waste and inefficiency and so is essential for an efficient allocation of healthcare resources. Methods: We used systematic review methods to search the literature across several electronic databases for economic evaluations of treatments for stable coronary artery disease.  We critically appraised the literature found in searches, both against the CHEERS statement for quality reporting of economic evaluations and in terms of its usefulness for policy and decision-makers. Results: We retrieved a total of 308 references, 229 once duplicates were removed. Of these, 26 were excluded as they were not full papers (letters, editorials etc.), 55 were review papers, 50 were not cost-effectiveness analyses and 93 related to a highly specific patient sub-group or did not consider all treatment options.  This left five papers to be reviewed in full. Conclusions: The current cost-effectiveness evidence does not support the increased use of PCI that has been seen in Australia and internationally. Due to problems with accessibility, clarity and relevance to policy and decision-makers, some otherwise very scientifically rigorous analyses have failed to generate any policy changes.

Clinical, humanistic, and economic outcomes between drug-eluting stent (DES) and bare metal stent (BMS): 18-month follow-up study

BACKGROUND

Percutaneous coronary intervention (PCI) is one of the most performed interventions for ischemic heart diseases. In Hong Kong, the total number of patient discharges and deaths for ischemic heart diseases in 2009 was 33,363, including 4,360 deaths. There are over 5,000 cases of PCI yearly. This study aimed to compare clinical, economic, and humanistic outcomes among patients receiving drug-eluting stent (DES) or bare metal stent (BMS) in Hong Kong.

METHODS

Patients who received stent implantation between September 15, 2009 and October 11, 2010 in Prince of Wales Hospital, Hong Kong, were recruited and followed for 18 months. Occurrence of major adverse cardiac events (cardiac death, non-fatal MI, TLR and TVR) was employed as the clinical outcome measurements. Improvement in quality-of-life by stent interventions was measured as quality-adjusted life-year (QALY). EQ-5D questionnaire was adopted to assess the QALY gained. Cost-utility analysis and cost-effectiveness analysis for BMS and DES were employed as the economic outcome measurement.

RESULTS

Six hundred and eighty-four patients (DES = 402; BMS = 282) were included. From 0-18 months, TLR rate (2.7% vs 3.5%, p = .549) and TVR rate (3.7% vs 6.4%, p = .111) were lower in the DES group, but without statistical significance. EQ VAS (71.06 ± 14.56 vs 71.07 ± 16.57, p = .998) and utility score (0.81 ± 0.17 vs 0.78 ± 0.16, p = .162) were comparable between DES and BMS group. Overall, the cost per QALY gained was HKD + 1,178,100 and ICER was HKD + 187,000 (1USD = 7.8 HKD).

CONCLUSIONS

No significant difference in TVR, TLR rates, EQ VAS, and utility score was found between the DES and BMS group. The higher cost of index procedure for the DES group was found to be partly offset by reduced cost of follow-up, offering cost-effectiveness in ACS patients, predominantly in STEMI patients. DES was recommended for STEMI patients.

Contemporary Context of Drug-Eluting Stents in Brazil: A Cost Utility Study

BACKGROUND

Although drug-eluting stents (DES) have been widely incorporated into clinical practice in developed countries, several countries restrict their use mainly because of their high cost and unfavorable incremental cost-effectiveness ratios (ICER).

OBJECTIVE

To evaluate the cost-effectiveness of DES in comparison with bare-metal stents (BMS) for treatment of coronary artery disease (CAD).

DESIGN

Markov model.

DATA SOURCES

Published literature, government database, and CAD patient cohort.

TARGET POPULATION

Single-vessel CAD patients.

TIME HORIZON

One year and lifetime.

PERSPECTIVE

Brazilian Public Health System (SUS).

INTERVENTION

Six strategies composed of percutaneous intervention with a BMS or 1 of 5 DES (paclitaxel, sirolimus, everolimus, zotarolimus, and zotarolimus resolute).

OUTCOME MEASURES

Cost for target vessel revascularization avoided and cost for quality-adjusted life year gained.

BASE CASE ANALYSIS

In the short-term analysis, sirolimus was the most effective and least costly among DES (ICER of I$20,642 per target vessel revascularization avoided), with all others DES dominated by sirolimus. Lifetime cumulative costs ranged from I$18,765 to I$21,400. In the base case analysis, zotarolimus resolute had the most favorable ICER among the DES (ICER I$62,761), with sirolimus, paclitaxel, and zotarolimus being absolute dominated and everolimus extended dominated by zotarolimus resolute, although all the results were above the willingness-to-pay threshold of 3 times the gross domestic product per capita (I$35,307).

SENSITIVITY ANALYSIS

In deterministic sensitivity analysis, results were sensitive to cost of DES, number of stents used per patient, baseline probability, and duration of stent thrombosis risk. The probabilistic sensitivity analysis demonstrated a probability of 81% for BMS being the strategy of choice, with 9% for everolimus and 9% zotarolimus resolute, at the willingness-to-pay threshold.

CONCLUSION

DES is not a good value for money in SUS perspective, despite its benefit in reducing target vessel revascularization. Since the cost-effectiveness of DES is mainly driven by the stents' cost difference, they should cost less than twice the BMS price to become a cost-effective alternative.

Using meta-regression analyses in addition to conventional systematic review methods to examine the variation in cost-effectiveness results - a case study

Background

Systematic reviews of cost-effectiveness analyses summarize results and describe study characteristics. Variability in the study results is often explained qualitatively or based on sensitivity analyses of individual studies. However, variability due to input parameters and study characteristics (e.g., funding or study quality) is often not statistically explained. As a case study, a systematic review on the cost-effectiveness of drug-eluting stents (DES) versus bare-metal stents (BMS) using meta-regression analyses is performed to explore the usefulness of such methods compared with conventional review methods.

Methods

We attempted to identify and review all modelling studies published until January 2012 that compared costs and consequences of DES versus BMS. We extracted general study information (e.g., funding), modelling methods, values of input parameters, and quality of the model using the Philips et al. checklist. Associations between study characteristics and the incremental costs and effectiveness of individual analyses were explored using regression analyses corrected for study ID.

Results

Sixteen eligible studies were identified, with a combined total of 508 analyses. The overall quality of the models was moderate (59 % ± 15 %). This study showed associations (e.g., type of lesion) that were expected (based on individual studies), however the meta-regression analyses revealed also unpredicted associations: e.g., model quality was negatively associated with repeat revascularizations avoided.

Conclusions

Meta-regressions can be of added value, identifying significant associations that could not be identified using conventional review methods or by sensitivity analyses of individual studies. Furthermore, this study underlines the need to examine input parameters and perform a quality check of studies when interpreting the results.

Electronic supplementary material

The online version of this article (doi:10.1186/s12913-015-1230-4) contains supplementary material, which is available to authorized users.

Changes in the Practice of Coronary Revascularization between 2006 and 2010 in the Republic of Korea

PURPOSE

Evidence suggests that technological innovations and reimbursement schemes of the National Health Insurance Service may have impacted the management of coronary artery disease. Thus, we investigated changes in the practice patterns of coronary revascularization.

MATERIALS AND METHODS

Revascularization and in-hospital mortality among Koreans ≥20 years old were identified from medical claims filed between 2006 and 2010. The age- and sex-standardized procedure rate per 100,000 person-years was calculated directly from the distribution of the 2008 Korean population.

RESULTS

The coronary revascularization rate increased from 116.1 (95% confidence interval, 114.9-117.2) in 2006 to 131.0 (129.9-132.1) in 2010. Compared to the rate ratios in 2006, the rate ratios for percutaneous coronary intervention (PCI) and coronary artery bypass graft (CABG) surgery in 2010 were 1.16 (1.15-1.17) and 0.80 (0.76-0.84), respectively. Among patients who received PCI, the percentage with drug-eluting stents increased from 89.1% in 2006 to 93.0% in 2010. In-hospital mortality rates from PCI significantly increased during the study period (p=0.03), whereas those from CABG significantly decreased (p=0.01). The in-hospital mortality rates for PCI and CABG were higher in elderly and female patients and at the lowest-volume hospitals.

CONCLUSION

The annual volume of coronary revascularization continuously increased between 2006 and 2010 in Korea, although this trend differed according to procedure type. A high percentage of drug-eluting stent procedures and a high rate of in-hospital mortality at low-volume hospitals were noted.

[Cardiovascular diseases in the focus of health economics. The example of drug-eluting vascular stents in coronary heart disease]

Coronary heart disease is an important disorder in Western industrialized societies, with regard to both the epidemiologic and economic burden of illness. A modern therapeutic strategy consists of coronary interventions and the implantation of drug-eluting vascular stents. The cost-effectiveness of such drug-eluting stents has been an important subject of health-economic evaluation research in recent years. This article presents two examples of such studies and deals with the question whether existing study projects are able to provide sufficient evidence for allocation decisions in health care. On this basis we discuss important challenges for future health economic analysis. A key conclusion is the need for long-term and cross-sectoral evaluation strategies that could be based on routinely collected health care data. Supplemented by health economic results from clinical trials, the use of such data would lead to a broader data basis for allocation decisions in health care.

Cost effectiveness of drug-eluting stents in acute myocardial infarction patients in Germany: results from administrative data using a propensity score-matching approach

BACKGROUND

The high number of patients with acute myocardial infarction (AMI) has facilitated greater research, resulting in the development of innovative medical devices. So far, results from economic evaluations that compared drug-eluting stents (DES) and bare-metal stents (BMS) have not shown clear evidence that one intervention is more cost effective than the other.

OBJECTIVE

The aim of this study was to measure the cost effectiveness of DES compared with BMS in routine care.

METHODS

We used administrative data from a large German sickness fund to compare the costs and effectiveness of DES and BMS in patients with AMI. Patients with hospital admission after AMI in 2004 and 2005 were followed up for 1 year after hospital discharge. The cost of treatment and survival after 365 days were compared for patients treated with DES and BMS. We adjusted for covariates defined according to the Ontario Acute Myocardial Infarction Mortality Prediction Rules using propensity score matching. After matching, we calculated incremental cost-effectiveness ratios (ICERs) by (i) using sample means based on bootstrapping procedures and (ii) estimating generalized linear mixed models for costs and survival.

RESULTS

After propensity score matching, the sample included 719 patients treated with DES and 719 patients treated with BMS. A comparison of sample means resulted in average costs of € 12 714 and € 11 714 for DES and BMS, respectively, in 2005 German euros. Difference in 365-day survival was not statistically significant (700 patients with DES and 701 with BMS). The ICER of DES versus BMS was -€ 718 709 per life saved. Bootstrapping resulted in DES being dominated by BMS in 54.5% of replications and DES being a dominant strategy in 2.7% of replications. Results from regression models and sensitivity analyses confirm these results.

CONCLUSION

Treatment with DES after admission with AMI is less cost effective than treatment with BMS. Our results are in line with other cost-effectiveness analyses that used administrative data, i.e. under routine care conditions. However, our results do not preclude that DES may be cost effective in specific patient subgroups.

Health economic evaluation of the use of drug-eluting stents : First results from the Drug-Eluting Stent Registry (DES.de)

OBJECTIVE: The purpose of the economic evaluation of the German Drug-Eluting Stent (DES) registry includes the investigation of the economic impact and cost-effectiveness of DES compared to bare-metal stents (BMS) and between paclitaxel-eluting (PES) and sirolimus-eluting stents (SES). Here, methodology and initial results are presented. METHODS: Patients were recruited in 2005 and 2006 in 87 centres across Germany. Selection of PES, SES, or BMS was made at the discretion of the cardiologists in charge. Clinical, economic, and quality of life (QoL) data were collected at baseline and up to 12 months. Group comparisons were conducted using Fisher's exact and t test. RESULTS: Overall, 3,930 patients were enrolled: 3,471 (75% male, 65 ± 11 years) received DES and 458 (74% male, 67 ± 11 years) BMS. Among the DES patients, 1,821 received PES (75% male, 65 ± 10 years) and 1,600 SES (76% male, 65 ± 11 years). There were baseline differences in clinical and procedural characteristics but not in QoL. During the hospital stay, major adverse cardiac and cerebrovascular events occurred in 1.6% of DES (PES 1.9%, SES 1.1%) and 2.2% of BMS patients (BMS vs. DES, PES, and SES p = 0.327, 0.706, and 0.098, respectively). Hospital treatment costs were 4,989 ± 1,284  and 3,609 ± 924 , respectively, in DES and BMS patients (p < 0.001) with no significant difference between PES and SES. CONCLUSION: The economic evaluation of the large DES registry demonstrates increased initial hospitalisation costs associated with DES compared to BMS. Further analysis of the economic impact and cost-effectiveness of DES will provide estimates on large "real world" patient populations for decision makers and aid in reimbursement decisions of DES within the German and other health care systems.

Multi-Link Vision stent vs. first-generation drug-eluting stents: systematic review and meta-analysis

BACKGROUND

Since its introduction, the cobalt chromium alloy MULTI-LINK VISION stent (MLV) has been extensively investigated thus leading to the largest amount of data so far available for a bare metal stent. Aim and

METHODS

Systematic review and meta-analysis (according to Cochrane collaboration guidelines) aiming at summarizing the real world safety and efficacy of MLV stent. Endpoints of interest were: major adverse events [(MAE) combination of overall death and non-fatal myocardial infarction, MI], and target vessel revascularization (TVR). Rate of stent thrombosis was also assessed.

RESULTS

Eleven studies finally retrieved totalling 5539 patients [7 study registries, 4243 patients and 4 randomized controlled trials (RCTs) comparing MLV vs. first generation of drug-eluting stent (DES) (paclitaxel or sirolimus eluting), (RCTs) 1296 patients]. Across study registries, at a mean follow-up of 11.1 months, MLV was associated with a 5.3% risk of MAE, 3% of death, 2.3% of MI and a 9% of TVR. Risk of ST was 0.5%. Compared to first generation of DES in RCTs, at a mean follow-up of 10.5 months, MLV achieved similar results in terms of MAE, death and MI. On the other hand, MLV was associated with a double risk of TVR [OR 2.01 (1.34-3.01), P < 0.001, number needed to treat 18 (13-40)]. Overall, in stent late loss with MLV was 0.81 mm (±0.51), while the in segment late loss was 0.61 mm (±0.5). Risk of stent thrombosis was equivalent. Of note, performance of MLV in terms of safety, efficacy and risk of repeat revascularization was quite consistent across all the published studies, despite inherent differences in study design, clinical setting, complexity of the lesions and ethnicity.

CONCLUSION

Compared to first-generation DES, MLV showed substantial equivalence with respect to hard clinical endpoints. Data are consistent in study registries and RCTs meaning that the overall performance of MLV is quite predictable and reproducible into the wide spectrum of clinical settings.

Downstream coronary effects of drug-eluting stents

BACKGROUND

Antiproliferative agents used in drug-eluting stents (DES) attenuate atherosclerosis, yet DES implantation has been linked to endothelial dysfunction. The downstream effects of DES on new lesion formation have not been previously directly examined. We sought to compare the development of de novo stenoses and need for treatment in the downstream coronary vessel of patients treated with DES or a bare-metal stent.

METHODS

Angiographic images and procedural information were prospectively collected on 463 adults who underwent implantation of a single stent in a proximal coronary artery, had an appropriate control vessel for comparison, and subsequently returned for intervention. Propensity matching identified 89 pairs of patients. End points were defined as angiographic identification of a de novo stenosis or need for secondary intervention in the downstream vessel within 12 months of initial intervention.

RESULTS

In the overall (P < .01) and propensity-matched cohort (P = .01), there was reduced risk of new lesions downstream to DES. No difference was seen in respective control vessels (P = .14 and P = .99). A reduced need for downstream intervention with DES was seen in both the overall (P = .01) and propensity-matched cohorts (P = .04). No difference was seen in the control vessels (P = .98 and P = .36). Multivariate proportional hazards modeling of known atherosclerosis risk factors identified stent type as the sole predictor for downstream lesions (P < .01) and downstream events (P = .02).

CONCLUSIONS

Patients receiving DES appear less likely to develop downstream stenoses and events compared with patients receiving bare-metal stents, suggesting beneficial downstream drug delivery.

Cost analysis of four major drug-eluting stents in diabetic populations

AIM

To use an indirect comparisons approach and conduct a cost analysis comparing four drug-eluting stents (DES) from a United States (US) payer (i.e., fixed-fee reimbursement) perspective.

METHODS AND RESULTS

Studies were chosen that randomised two or more DES in diabetic patients. A one-year target lesion revascularisation (TLR) risk for Taxus was first derived. Risk Ratios (RRs) for each DES versus Taxus were calculated through meta-analyses. The RRs were multiplied by the average TLR risk for Taxus to estimate DES TLR risks. Estimates were added to a budget-impact model, along with utilisation and reimbursement rates for diagnosis-related groups. Budgets were calculated, assuming 100% stent use and 200,000 diabetic beneficiaries. One-year TLR risks were estimated to be 3.2%, 7.1%, 6.9% and 7.9% for Cypher, Endeavor, Taxus and Xience respectively. By substituting Cypher for DES with higher TLR, results predicted annual cost-savings greater than $146 million per population ($ 733 per patient). Results were comparable when assuming no difference in TLR risk between Endeavor, Taxus and Xience.

CONCLUSIONS

When outcomes from trials of diabetic populations are analysed and used in a budget-impact model from a US payer perspective, the use of Cypher is associated with lower TLR rates, which translates into large potential cost savings.

Serum Inflammatory and Immune Marker Response After Bare-Metal or Drug-Eluting Stent Implantation Following Percutaneous Coronary Intervention

We assessed the changes in serum antiheat shock protein (HSP)-27 antibody and high-sensitivity C-reactive protein (hsCRP) levels, following the placement of a drug-eluting stent (DES) or bare-metal stent (BMS) in patients with stable coronary artery disease. Either a BMS or DES was implanted in 137 patients (82 BMS; 55 DES). Anti-HSP27 and hsCRP levels were measured 24 hours before and 24 hours after stenting. Median hsCRP serum levels increased significantly to 60.78 (10.13-84.87) and 77.80 (50.00-84.84) mg/L for BMS and DES groups (P = .006 and P = .000, respectively); this increase did not differ significantly between the 2 groups. Median anti-HSP27 antibody levels decreased to 0.26 (0.17-0.49) and 0.21 (0.16-0.29) absorbency units in BMS and DES groups (P = .045 and P = < 0.001, respectively). The changes in anti-HSP27 antibody titers were significant between the 2 groups (P = .015). Bare-metal stent and DES differ in stimulation of immune rather than inflammatory responses. Less stent restenosis after DES compared with BMS implantation could, in part, be attributed to differences in immune responses.