FREEDOM Study Reveals CABG is More Cost-Effective than PCI for Patients with Diabetes

According to late-breaking clinical trial research results presented at the American Heart Association 2012 Scientific Sessions, coronary artery bypass grafting (CABG) is more cost-effective in the long term than angioplasty using drug-eluting stents for patients with diabetes and multiple clogged arteries.

The Future Revascularization Evaluation in Patients with Diabetes Mellitus: Optimal Management of Multivessel Disease (FREEDOM) trial compared the clinical effectiveness of percutaneous coronary intervention (PCI) using drug-eluting stents with CABG in a cohort of 1,900 patients with diabetes and multiple blockages in their coronary arteries.

1,900 randomized patients were enrolled in the study, with 947 patients assigned to CABG and 953 assigned to PCI. Due to some patients withdrawing from the study, a total of 911 underwent revascularization with CABG and 944 with PCI. The study population was 72% male (n=1328), 28% female (n=527), with patients divided nearly evenly by age (624 patients under age 60, 621 age 60-69, and 610 age 70 or older).

Investigators reported that after two years of follow-up, patients treated with CABG had a lower risk of death, myocardial infarction, but a greater risk of stroke.

Analysis of cost-effectiveness and other economic data from the FREEDOM study showed that not only was CABG associated with better clinical outcomes compared to PCI with drug-eluting stents, it was also more cost-effective in the long term, despite higher initial costs, due to the greater follow-up costs associated with PCI (including greater need for repeat revascularizations, and higher mortality).

The higher initial cost of CABG was due in part to longer hospital stays and more post-procedure complications compared to PCI. Researchers put the initial cost for CABG at $34,467 (including $9,776 for index procedures, $19,521 for hospital room and ancillary services, and $5,170 for physician fees). Initial cost of PCI with drug-eluting stents was calculated to be $25,845 ($12,998 for index procedures, $9,880 for room and ancillary services, and $2,967 for physician fees).

Although CABG was associated with an initial cost that was $8,622 higher than PCI, after the first five years that cost difference had decreased to only $3,600 due to the higher follow-up costs associated with PCI. The data showed that CABG was associated with a lifetime incremental cost-effectiveness ratio of $8,132 per quality-adjusted life-year (QALY) gained, which is “well below the figure of $50,000 per QALY widely accepted by health policy makers as defining the upper boundary of cost effectiveness.”

Lead investigator Elizabeth Magnuson Sc.D., of the University of Missouri-Kansas City’s Saint Luke’s Mid America Heart Institute, said that these results “demonstrate that bypass surgery is not only beneficial from a clinical standpoint, but also economically attractive from the perspective of the US health care system” because of the “large number of people with diabetes who are in need of procedures to unblock clogged arteries.”