Qualitative coronary artery calcium assessment on CT lung screening exam helps predict first cardiac events

Katherine B. Malcolm, Danya L. Dinwoodey, Michael C. Cundiff, Shawn M. Regis, Andrea K. Borondy Kitts, Christoph Wald, Miranda L. Lynch, Wael Al-Husami, Andrea B. McKee, Brady J. McKee

Abstract

A total of 1,513 individuals underwent CTLS. Downstream data, pre-test cardiac risk factors and CAC scores were available for 88.3% (1,336/1,513). The average length of follow-up was 2.64 (SD ±0.72) years. There were a total of 43 events, occurring in 1.55% (6/386) of patients with mild CAC, 3.24% (11/339) of patients with moderate CAC, and 8.90% (26/292) of patients with marked CAC. There were no events among patients with no reported CAC (0/319). Using multivariable logistic modeling, the increased odds of an initial cardiac event was 2.56 (95% CI, 1.76–3.92, P<0.001) for mild CAC, 6.57 (95% CI, 3.10–15.4, P<0.001) for moderate CAC, and 16.8 (95% CI, 5.46–60.3, P<0.001) for marked CAC, as compared to individuals with no CAC. Time to event analysis showed distinct differences among the four CAC categories (P<0.001).