Low short-term and long-term cardiovascular and all-cause mortality in absence of coronary artery calcium: A 22-year follow-up observational study from large cohort

Abstract

Objectives: We sought to evaluate the gender-specific predictive value of coronary artery calcium (CAC) score on all-cause mortality and cardiovascular disease (CVD) mortality in individuals with and without diabetes mellitus (DM).

Background: CAC score is a robust predictor of CVD and all-cause mortality during long-term follow-up in large cohorts in adults with DM. However, less is known about its sex-specific impact on all-cause mortality in DM.

Methods: We evaluated 25,563 asymptomatic participants with no known history of coronary artery disease (CAD) who underwent clinically indicated CAC. 1999 (7.8%) individuals had diabetes. CAC was characterized as an Agatston score of 0, 1-99, 100-300, and ≫300. We evaluated the association between CAC and all-cause mortality and CVD mortality.

Results: Overall, 1345 individuals died (5.3%) from all causes during a mean follow-up of 14.7 ± 3.8 years. CAC score was 0 in 57.5% females and 34.4% of males without DM, while 36.6% females and 20.3% males with DM had CAC-0. The frequency of CAC ≫ 300 was 18% and 36% in females and males with DM, respectively. CAC score of zero was associated with low all-cause mortality event rate in females and males with diabetes (1.7 and 2.5 events per 1000 person-years, respectively). Cardiovascular mortality per 1000 person years was ≪1 in females and males with CAC score of 0 irrespective of their diabetes. Adjusted multivariable analysis, compared to CAC-0, HR for all-cause mortality associated with CAC 1-99, 100-299 and ≫300 were 1.74(95% CI 0.65, 4.63, P-0.20), 5.54(95% CI 2.16, 14.22, P ≪ 0.001) and 5.75(95% CI 2.30, 14.37, P ≪ 0.001) in females with DM respectively; in males with DM HR associated with CAC 1-99, 100-299 and ≫300 were 1.87(95% CI 0.95, 3.66, P-0.06), 2.15(95% CI 1.05, 4.38, P-0.035) and 2.60(95% CI 1.34, 5.0, P-0.004), respectively.

Conclusion: Presence of subclinical atherosclerosis varies among individuals with DM. The absence of CAC was associated with very low cardiovascular as well as all-cause mortality events in all subgroups during long term follow-up.

Keywords: All-cause mortality; Coronary artery calcium; Diabetes in males and females.