Medicare's policy on carotid stents limited use to hospitals meeting quality guidelines yet did not hurt disadvantaged

Abstract

Medicare began covering the use of carotid stents to treat arterial blockages in 2005 under an innovative policy requiring hospitals to meet quality-of-care benchmarks before seeking reimbursement. By restricting carotid stent provision to a smaller subset of US hospitals than those typically adopting new cardiovascular technologies, this policy could have disproportionately reduced the availability of this technology for minority, low-income, and rural patients. Such patients are often served by hospitals less able than others to meet increasingly stringent quality requirements. However, our analysis of hospitals that provided stents during 2005-07 demonstrated that although 21-38 percent fewer hospitals offered stents than offered other types of interventional cardiovascular procedures, such as heart bypass grafts, stents were no less available in localities with substantial poor, black, or rural populations than they were in other areas. Our study provides important evidence that the carotid stent coverage policy met its goal of limiting the adoption of the technology by hospitals that weren't well prepared to provide it-while still maintaining equitable availability of the technology. Therefore, it may be a useful model for future Medicare coverage decisions.

Exhibit 1

Carotid Stent Certified Hospitals: 2005–2007 Source: Centers for Medicare and Medicaid Services’ list of CAS-approved facilities. Notes: Rates of CMS certification of U.S. hospitals for the provision of carotid arterial stenting to Medicare beneficiaries. Dark red bars indicate U.S. hospitals newly certified during each calendar quarter. Lighter red bars indicate the cumulative number of U.S. hospitals certified prior to the calendar quarter.

Exhibits 2 and 3

Hospital Referral Regions’ Adoption of Carotid Stenting Sources: Medicare facility claims; Centers for Medicare and Medicaid Services’ list of carotid-stent-certified facilities. Notes: Maps of U.S. Hospital Referral Regions indicating market penetration of carotid stenting in early 2005 (upper map) and late 2007 (lower map). Blue shading indicates regions with less than 33% market penetration.

Exhibit 4. Relative Use of Major Cardiovascular Technologies by U.S. Hospitals

Source: Medicare facility claims, October-December, 2007. Notes: Utilization rates of carotid stents and comparable major cardiovascular technologies among the U.S. hospitals technologically equipped to provide interventional cardiovascular procedures. Blue bars indicate rates of use among all technologically equipped U.S. hospitals (n=1,449). Red bars indicate rates of use in the subset of U.S. hospitals (n=1,141) in hospital referral regions with low pre-2005 utilization of carotid stenting.