Author + information
- John Leigh,
- John McEvoy,
- Veit Sandfort,
- Waqas Qureshi,
- John Carr,
- Elizabeth C. Oelsner,
- Matthew Budoff,
- David Herrington and
- Joseph Yeboah
Introduction: The USPSTF recommends screening for lung cancer with annual low-dose CT (LDCT) in certain patients. Criteria include age 55-80 years, at least 30 pack-year smoking history, and current smoking or having quit within 15 years. Coronary artery calcium (CAC) is not routinely reported in these scans. The utility of CAC for cardiovascular disease (CVD) risk stratification is unclear in this group. We assess the predictive value and discriminative ability of CAC in smokers using participants of the Multi-Ethnic Study of Atherosclerosis (MESA).
Methods: 3278/6814 (48.1%) participants were smokers (current or former) and 481/3274 (14.7%) were LDCT screening eligible (LDCT-SE). Cox proportional hazard models were used to assess the association between CAC and CVD events adjusting for age, sex, race, diabetes status, hypertension status, and statin use. CVD events were defined as sudden cardiac death, fatal and non-fatal MI, fatal and non-fatal stroke.
Results: Smokers had a mean age of 62.2, were 43.4% female, and had a mean of 23.0 pack years smoking. LDCT-SE subjects had a mean age of 65.3, was 39.1% female, and had mean of 56.7 pack years smoking. 13.2% of all smokers and 20.8% LDCT-SE had CVD events after 10 years of follow up. The median (IQR) of CVD risk using the Pooled Cohort Equation (PCE) was 10.8% (4.8-20.6%) and 14.3% (8.9-23.9%) for LDCT-SE. The CVD event rate was higher in participants with CAC compared to those without in smokers (18.4% vs 6.6%) and LDCT-SE (23.3% vs. 14.2%). In multivariate models, the presence of CAC was associated with CVD events in smokers [HR 2.08 (95% CI: 1.64-2.67)] and in LDCT-SE [1.91 (1.15-3.31)]. In predicting CVD events, the PCE had an AUC of 0.696 in all smokers and 0.545 in LDCT-SE. Adding CAC to the PCE did not significantly improve the AUC in smokers (0.706) and in LDCT-SE (0.569).
Conclusions: In this cohort, 14.7% of all smokers (7.1% of subjects) were LDCT-SE. Even though CAC was predictive of CVD events, the addition of CAC to the PCE produced very modest discrimination for CVD events in all smokers and LDCT-SE participants. The addition of CAC to traditional risk calculators may have a limited role in CVD risk assessment in LDCT-SE subjects given their high baseline risk.
Poster Hall, Hall C
Saturday, March 18, 2017, 9:45 a.m.-10:30 a.m.
Session Title: Non Invasive Imaging: Coronary Calcium Scoring and CV Risk Assessment
Abstract Category: 27. Non Invasive Imaging: CT/Multimodality, Angiography, and Non-CT Angiography
Presentation Number: 1198-238
- 2017 American College of Cardiology Foundation