SAN DIEGO– After the first 90 days, there is very little difference in costs out to 3 years between CT angiography and functional testing in the initial evaluation of stable patients with new chest pain, an economic substudy of the PROMISE trial showed.
“CT coronary angiography may not be the ‘holy grail’ of diagnostic tests that we once envisioned, but its more liberal use based on the results of PROMISE may improve some aspects of patient care and I don’t think will be a major new economic burden on the health care system,” study author Dr. Daniel B. Mark said at the annual meeting of the American College of Cardiology.
The PROMISE trial, also presented at the ACA meeting, found no advantage with respect to hard clinical outcomes between the two initial testing strategies, but CTA led to fewer catheterizations showing no obstructive disease and a twofold increase in revascularizations.
The economic analysis involved initial test technical fees, hospital-based facility costs, and physician professional fees for testing and hospital services for 96% of the 9,649 patients in the study.
The estimated cost of CT angiography, including physician fees and technical fees, was $404, compared with $174 for exercise treadmill testing, $501 for echocardiography with pharmacologic stress, $514 for echo with exercise stress, $946 for nuclear testing with exercise stress, and $1,132 for nuclear testing with pharmacologic stress, said Dr. Mark, director of outcomes research at Duke Clinical Research Institute, Durham, N.C.
The trend toward higher costs with CT angiography was driven largely by more revascularizations, with very in little added costs occurring after 90 days, he noted.
An analysis that factored in what was done to patients after their initial test showed CT angiography was more expensive than functional testing by an average of $279 at 90 days, $358 at 1 year, $388 at 2 years, and $694 at 3 years. The 95% confidence intervals were wide, so none of the differences were statistically significant, he said.
Nick Piegari/Frontline Medical Communications
Dr. Daniel B. Mark
A number of patients underwent very expensive noncardiovascular procedures in the third year that bumped the average cost up in the CT arm, “but we don’t think this has anything to do with the strategies to which they were randomized,” Dr. Mark explained.
Caveats to the analysis include use of an external data source (Premier Research Database) for initial diagnostic testing costs, outpatient medications were not counted, and significant deviations in testing costs by centers that might alter cost results of the two strategies. Quality of life and employment status are also still being analyzed, Dr. Mark said.
A cost-effectiveness analysis was not performed because CT angiography outcomes were not superior as hypothesized in PROMISE.
The study was funded by the National Institutes of Health. Dr. Mark disclosed consulting for Milestone, Medtronic, CardioDx, and St. Jude Medical and research grants from the NIH, Eli Lilly, AstraZeneca, Gilead, AGA Medical, and Bristol-Myers Squibb.