CORONARY ARTERY CALCIFICATION AND CARDIOVASCULAR EVENTS IN CKD-PATIENTS NOT ON DIALYSIS

INTRODUCTION AND AIMS: In dialysis patients presence and fast progression of coronary calcifications (CAC) are associated with cardiovascular (CV) events. Higher prevalence and faster progression of CAC have been found in chronic kidney disease patients not yet on dialysis (CKD patients) compared to controls. In this study the relationship between CAC and CV events has been evaluated in CKD patients. METHODS: Consecutive CKD patients were studied. Exclusion criteria were: symptomatic coronary disease; arrhythmia; history of myocardial infarction, coronary bypass surgery or angioplasty; stroke; progressive renal disease; nephrotic syndrome. Blood chemistry, calcium, phosphorus, parathyroid hormone (i-PTH), homocysteine, C-reactive protein, triglycerides, cholesterol, HDL-cholesterol, LDL-cholesterol, were measured. CAC were assessed by measuring total calcium score (TCS; Agatston Units) with spiral CT. At the end of follow-up [2.0 (1.1-3.0) yrs] TCS was repeated for assessing CAC progression (annualized progression) and fatal and not fatal CV events (stroke, acute miocardial infarction, angina) were recorded. Patients were divided in 3 groups: TCS 400; values indicating low, moderate, high CV risk in general population. Data are given as median (interquartile range). RESULTS: N. 181 patients were enrolled. Patients with TCS >100 were older [68 (59-72); p<0.0001] and more frequently diabetics, had lower GFR [ 42 (23-58) ml/min; p<0.0001], faster CAC progression (p<0.0001), longer duration of hypertension [120 (36-189) months; p<0.01], higher traditional CV risk factors (p<0.049). Among groups no differences were found in variables of mineral metabolism, inflammation, dyslipidemia. Survival rate is shown in figure. No difference in CV events was found in patients with TCS≥100. Relative hazard for CV events, according to annualized CAC progression, is reported in table. table 1 ANNUALIZED CAC PROGRESSION (percentile) RELATIVE HAZARD IN PATIENTS WITH TCS<100 RELATIVE HAZARD IN PATIENTS WITH TCS≥100 ≤25 0.41 4.7 25-75 0.41 2.8 >75 3.3 3.0 long-rank test p=0.0015 CONCLUSIONS: The present study shows that CAC may be responsible for fatal and not fatal CV events even in CKD patients. In CKD patients TCS<100 may be regarded as a predictor of CV events being associated with fatal and not fatal outcomes; this is in contrast to general population. In patients with baseline TCS<100 increased annualized CAC progression is associated to higher relative hazard risk for CV events; this association is not evidenced in patients with TCS≥100. Difference in plaque stability may explain discrepant survival courve and relative hazard between patients with TCS