Coronary Artery Calcification Score and the Progression of Chronic Kidney Disease

Abstract

Background: An elevated coronary artery calcification score (CACS) is associated with increased cardiovascular disease risk in patients with CKD. However, the relationship between CACS and CKD progression has not been elucidated.

Methods: We studied 1936 participants with CKD (stages G1-G5 without kidney replacement therapy) enrolled in the KoreaN Cohort Study for Outcome in Patients With CKD. The main predictor was Agatston CACS categories at baseline (0 AU, 1-100 AU, and >100 AU). The primary outcome was CKD progression, defined as a ≥50% decline in eGFR or the onset of kidney failure with replacement therapy.

Results: During 8130 person-years of follow-up, the primary outcome occurred in 584 (30.2%) patients. In the adjusted cause-specific hazard model, CACS of 1-100 AU (hazard ratio [HR], 1.29; 95% confidence interval [CI], 1.04 to 1.61) and CACS >100 AU (HR, 1.42; 95% CI, 1.10 to 1.82) were associated with a significantly higher risk of the primary outcome. The HR associated with per 1-SD log of CACS was 1.13 (95% CI, 1.03 to 1.24). When nonfatal cardiovascular events were treated as a time-varying covariate, CACS of 1-100 AU (HR, 1.31; 95% CI, 1.07 to 1.60) and CACS >100 AU (HR, 1.46; 95% CI, 1.16 to 1.85) were also associated with a higher risk of CKD progression. The association was stronger in older patients, in those with type 2 diabetes, and in those not using antiplatelet drugs. Furthermore, patients with higher CACS had a significantly larger eGFR decline rate.

Conclusion: Our findings suggest that a high CACS is associated with significantly increased risk of adverse kidney outcomes and CKD progression.

Keywords: chronic renal disease; clinical nephrology; coronary artery disease; coronary calcification; vascular calcification.

Graphical abstract

Figure 1.

Flow diagram of the study subjects.

Figure 2.

The probability of kidney survival rates according to coronary artery calcification score categories. The probability of kidney survival rates was estimated with cumulative incidence function and compared by Gray’s test (P<0.001). CACS, coronary artery calcification score.

Figure 3.

Cubic spline analysis for risk of adverse clinical events by coronary artery calcification score. Coronary artery calcification score was calculated as log transformation and expressed as coronary artery calcification score per 1-SD log.

Figure 4.

Multivariable-adjusted hazard ratios for CKD progression according to coronary artery calcification score categories and per 1-SD log of coronary artery calcification score, stratified by subgroups. Each hazard ratio was adjusted for covariates including sex, age, Charlson comorbidity index, smoking status, education level, body mass index, etiology of kidney disease, BP, eGFR, total cholesterol, HDL cholesterol, LDL cholesterol, high-sensitivity C-reactive protein, medications (antihypertensive drugs and lipid-lowering drugs), phosphate, intact parathyroid hormone, urinary protein-to-creatinine ratio, and fibroblast growth factor-23. CAC, coronary artery calcification; CI, confidence interval.