The Impact of New Cardiovascular Device Technology on Health Care Costs

Drug-eluting coronary stents (DESs) are widely used¹ and entail sizeable Medicare hospital expenditures.² However, the overall cost impact of DESs has not been well quantified. A clear understanding of how new technologies like DESs affect health care expenditures can provide insight into national trends in health care cost growth, of which new technology is presumably the leading driver.³ New technology may not only increase costs by being more expensive than previous treatments, but also by changing the patterns of care for chronic disease.⁴ Accordingly, we sought to assess the overall impact of DESs on Medicare expenditures in a nationally representative cohort of Medicare beneficiaries with coronary artery disease (CAD).

Because DESs were introduced in 2003, we calculated mean annual payer-perspective costs among patients with CAD during 2002 through 2006 (including 2002 costs as a baseline), in each US Hospital Referral Region (HRR)⁵ using a 5% random sample of fee-for-service Medicare beneficiaries, excluding patients younger than 66 years and older than 85 years (DES use declines markedly at older ages).⁶ Calculations were separately performed on each of 3 CAD subcohorts categorized annually by clinical events: patients with acute myocardial infarction (AMI), patients with acute coronary syndrome (ACS) but no AMI, and patients without ACS. We did not assume that DES-associated health care cost growth was confined solely to DES recipients; thus, cohorts included all patients with CAD regardless of treatments received. Costs included all facility and health care provider Medicare payments, including noncardiovascular costs, inflated to 2006 dollars using the consumer price index. This design captured costs downstream of major cardiovascular procedures and events, as patients were retained in the cohort through December 31, 2006, or until death. Annual DES rates within each HRR and subcohort were also calculated.

Substantial geographic variation in DES use across HRRs enabled measurement of the relationship between higher DES use and higher health care costs. Multivariable regression models were estimated, predicting annual HRR-level health care costs among patients with CAD as a function of the local DES rate, HRR “fixed effects” that controlled for time-invariant differences in costs across HRRs, and time-varying controls such as an annual HRR-specific medical cost index (controlling for geographic variability in health care inflation), patients' mean DxCG Risk Score (Verisk Health Inc, Waltham, Massachusetts) (predicting comorbidity-associated costs), and general time trend controls. Models were estimated separately for each subcohort.

To fully describe the national expenditure implications of the per-patient DES cost increases estimated by regression models, we computed the total change in national expenditures attributable to DESs by multiplying the total number of Medicare beneficiaries nationwide in each CAD subgroup by the per-patient 2002-2006 cost increase predicted by the models.

Calculations were derived from 1 981 088 Medicare beneficiaries with CAD, of whom 4.5% had a recent AMI, 3.4% had a recent noninfarction ACS, and 92% had no recent ACS. Between 2002 and 2006, DES use increased from 0% in all subcohorts to 23% among patients with AMI, 29% among patients with noninfarction ACS, and 1.1% among patients without ACS. Inflation-adjusted cost increases during 2002 through 2006 among CAD subcohorts ranged from 4.7% to 11.7%. Multivariable regressions indicated that each 1% increase in DES use was associated with a $28 mean per-patient cost increase (P = .009) among patients with AMI, a $35 increase (P < .001) among patients with noninfarct ACS, and a $133 increase (P = .003) among patients without ACS. These estimates implied a DES-attributable increase in annual expenditures on patients with AMI of $657, on patients with noninfarct ACS of $999, and on patients without ACS of $146 (Table). Because most patients with CAD were non-ACS cases, this subgroup composed the largest portion of DES-attributable national cost growth.

Drug-eluting coronary stents substantially increased costs for Medicare beneficiaries with CAD. The fraction of DES cost growth attributable to patients without ACS (68%) was much larger than the proportion of DESs received by this subcohort (33%), suggesting that DES use among patients without ACS was particularly cost amplifying (ie, DES introduction changed patterns of care for patients without ACS in a more costly manner than for patients with ACS). This is troubling, since the limited efficacy of percutaneous coronary intervention among patients without ACS, whether or not DESs are used, would not justify sizeable DES-related cost increases among patients without ACS.^7,8

This analysis contributes to understanding the cost-increasing effects of technology because the cost effects of DESs were measured beyond the price of the new technology itself. By measuring “global” costs among stable groups of patients over time, we captured temporal changes in both direct and indirect costs related to changing rates of DES use that occurred among patients who actually received the technology as well as nonrecipients.

This observational study could not establish whether the association between increased DES use and cost growth was causal. Use of DESs may be appropriate in selected patients without ACS and could deliver benefits at acceptable cost.⁹ Outpatient pharmaceutical costs were not included; these may have amplified or attenuated the DES-associated cost increase.

Drug-eluting cornary stents added $1.57 billion in annual Medicare expenditures among beneficiaries aged 66 to 85 years, with the largest cost increase occurring among patients without ACS.

Since the Food and Drug Administration approved the use of DESs for discrete, new (ie, previously untreated) partial blockages in patients' native coronary arteries (ie, not in bypass grafts), and only in relatively large vessels, and the Centers for Medicare and Medicaid Services simultaneously approved payment, the increase in use of DESs has been meteoric. By 2005, DESs were over 90% of all first stents placed. It is estimated that more than 60% of DESs are placed for off-label indications and these patients have higher adverse event rates than on-label usage. Groeneveld et al analyzed Medicare data on almost 2 million beneficiaries from 2002 through 2006 and found that the cost of DESs is staggering, adding $1.57 billion to our national health care bill paid by taxpayers. It is time to clearly define what the value of this extraordinary investment has been in terms of patient benefits and study the harms and determine if we are getting good value for this outlay.

Rita F. Redberg MD, MSc

Correspondence: Dr Groeneveld, Division of General Internal Medicine, Department of Medicine, University of Pennsylvania School of Medicine, 1229 Blockley Hall, 423 Service Dr, Philadelphia, PA 19104-4155 (petergro@mail.med.upenn.edu).

Published Online: April 25, 2011. doi:10.1001/archinternmed.2011.141. This article was corrected for a typographical error on May 27, 2011.

Author Contributions:Study concept and design: Groeneveld, Polsky, and Epstein. Acquisition of data: Groeneveld, Polsky, and Epstein. Analysis and interpretation of data: Groeneveld, Polsky, F. Yang, L. Yang, and Epstein. Drafting of the manuscript: Groeneveld, Polsky, and Epstein. Critical revision of the manuscript for important intellectual content: Groeneveld, Polsky, F. Yang, L. Yang, and Epstein. Statistical analysis: Groeneveld, Polsky, F. Yang, L. Yang, and Epstein. Obtained funding: Groeneveld. Study supervision: Groeneveld.

Funding/Support: This research was supported by the National Heart, Lung, and Blood Institute (grant 1R01HL086919) and by the Agency for Healthcare Research and Quality (grant 1R01HS018403). Dr Groeneveld was additionally supported by a Career Development Transition Award from the Department of Veterans Affairs' Health Services Research and Development Service, Washington, DC. This project was also funded, in part, under a grant from the Pennsylvania Department of Health, which specifically disclaims responsibility for any analyses, interpretations, or conclusions.

Previous Presentation: This study was presented orally at the American Heart Association Quality of Care and Outcomes Forum; May 20, 2010; Washington, DC.