Abstract 4143150: Long-term Effect of Screening for Coronary Artery Disease Using CT Angiography on Mortality and Cardiac Events in High-risk Patients with Diabetes: the FACTOR-64 Follow-up Study

Background: The FACTOR-64 study was a randomized controlled trial designed to assess whether routine screening for CAD by coronary computed tomography angiography (CCTA) in high-risk patients with diabetes followed by CCTA-directed therapy would reduce the risk of death and nonfatal coronary outcomes. Results at four years showed a lower revascularization rate (3.1% (14) vs. 8.9% (40), p<0.005) among the control group. But there was also a non-significant trend toward a lower incidence of all-cause mortality and nonfatal MI (hazard ratio, 0.82 [95% CI, 0.49-1.32]; p=0.38). Whether screening CCTA might have a more significant effect on the outcomes of patients after longer follow-up is unknown. Methods: The FACTOR-64 study randomized 900 patients (age = 61.5 years, males = 52%, Type 2 DM = 88%, DM duration = 13 years) with type 1 or type 2 diabetes for at least 3 to 5 years without CAD symptoms to screening with CCTA (n = 452) or standard national guidelines-based optimal diabetes care (n = 448). Standard primary prevention medical therapy or aggressive secondary prevention therapy with invasive coronary angiography was recommended based on CCTA findings. Enrollment occurred between July 2007 and May 2013, and follow-up extended to May 2024. Results: The mean follow-up time was 12.7±3.2 (CCTA=12.8±3.1; control=12.6±3.3, p=0.47) years. During longer-term follow-up after the initial four years, essentially the same numbers of further revascularizations (20 vs. 21) occurred in the CCTA group vs. the control group, thus continuing a significantly higher rate of revascularization among those receiving CCTA (Table). However, the composite and individual outcomes of all-cause mortality and nonfatal MI did not differ between the CCTA and control groups. Conclusion: Among asymptomatic patients with type 1 or type 2 diabetes followed for over twelve years, the use of CCTA to screen for CAD did not significantly affect the rates of all-cause mortality or nonfatal MI. This was despite an overall significantly increased use of revascularization among those receiving CCTA. These definitive findings do not support CCTA screening in this population.