Abstract 7: Increasing Use of Cardiovascular Devices and Rising Health Care Costs

Abstract

Background: Drug-eluting stents (DES) and implantable cardioverter-defibrillators (ICDs) are among the most common, and most costly, interventional therapies used in patients with cardiovascular disease. Medicare coverage decisions for DES and ICDs in 2003-2005 portended a large growth in health care costs for patients with coronary artery disease (CAD) and chronic heart failure (CHF). However, the actual fiscal impact of DES and ICDs is uncertain. Methods: We examined Medicare claims from 2003-2006 and separately identified cohorts of patients between ages 65-84 in each year diagnosed with CAD and CHF. Patients were assigned to one of 306 contiguous geographic localities (i.e., Dartmouth Atlas Hospital Referral Regions [HRRs]). For each disease group in each locality in each year, we calculated the average cost of care (including Medicare payments, supplemental insurance, and patient payments) as well as the average use rate of DES (for CAD) and ICDs (for CHF). We estimated time-series HRR-fixed-effects regression models predicting average costs, with % technology use as an independent variable. We included a measure of the annual change in costs of care for non-cardiovascular disease in each HRR to control for annual cost increases unrelated to ICDs/DES. Results: Average inflation-adjusted costs for CAD patients increased from $13,558 in 2003 to $14,215 in 2006 (p<0.001), while average costs for CHF patients increased from $18,930 in 2003 to $20,235 in 2006 (p<0.001). Time-series regressions indicated that a 1% increase in DES use among the CAD population resulted in $394 in higher mean costs (p<0.001), and 1% increased ICD use in the CHF population resulted in $627 in higher mean costs (p<0.001). In aggregate, between 2003-2006 the cost increase attributable to DES in the Medicare CAD population ages 65-84 was $4.97 billion (89% of total growth), and the cost increase in the Medicare CHF population attributable to ICDs was $893 million (29% of total growth). Conclusions: Rising use of DES and ICDs between 2003-2006 was associated with significantly higher costs for patients with CAD and CHF, respectively. Increased use of these technologies explained substantial fractions of the growth in health care costs for CAD and CHF patients during these years.