Introduction: We examined the association of coronary artery calcium (CAC) score with all-cause, cardiovascular disease (CVD), coronary heart disease (CHD), and cancer mortality according to smoking status.
Methods: A total of 53478 patients without known CHD (mean age 54.5 ± 10.5, 35% women, 9.6% current smokers) from CAC Consortium cohort, with data on smoking and CAC score, were included. We used Cox regression model to assess the association of mortality outcomes with CAC as a continuous variable (1 standard deviation (SD) increase in log-transformed CAC score) and categorical variable: CAC = 0 (reference), CAC=1-99, CAC=100-399, and CAC ≥400, in current smokers and nonsmokers. Models were adjusted for demographic and clinical characteristics.
Result: Over a median of 11.9 years, 2332 patients died from CVD (n=723), CHD (n=391), and cancer (n=875). One SD increase in log CAC score was associated with significantly increased Hazard Ratio (HR) for all outcomes of interest in current smokers and nonsmokers (Table). Among nonsmokers, compared to CAC=0, all CAC groups showed increased risk of all-cause mortality. Among smokers, patients with CAC scores of 100-399, and ≥400 showed significantly higher HRs for all-cause mortality. Smokers and nonsmokers with CAC=100-399 and ≥ 400 had significantly higher HRs for CVD and CHD mortality. Compared with nonsmokers without CAC, smokers showed increased risk for all of the outcomes of interests. The only exception was smokers without CAC that did not show significant HR for CHD (figure).
Conclusion: CAC score independently predicted the higher risk for all-cause, CVD, CHD and cancer mortality among smokers and nonsmokers.