OBJECTIVES The purpose of this study is to assess the independent association between early CKD (stages 1-3a) with coronary atherosclerosis and the feasibility of risk stratification of coronary atherosclerosis according to The Kidney Disease Outcomes Quality Initiative (K/DOQI) guidelines using non-invasive coronary angiography.

METHODS We consecutively enrolled 4297 asymptomatic subjects who underwent coronary CT angiography as part of a general health evaluation and had estimated glomerular filtration rates (eGFR) over 45 ml/min/1.73 m(2). Subjects were categorized from no CKD to stage 3a CKD, and multiple regression analyses for coronary atherosclerosis were performed.

RESULTS Early CKD was an independent risk factor for coronary artery disease (CAD) and obstructive CAD. However, neither the risk of CAD nor CACS >100 increased as stage of CKD advanced. The reason for unsuccessful stratification of coronary atherosclerosis risk was that the presence of proteinuria, which was used to define stages 1 and 2 CKD, was an independent risk factor for coronary atherosclerosis, but eGFR of 45-89 ml/min/1.73 m(2) was not associated with coronary atherosclerosis.

CONCLUSIONS Early CKD was an independent risk factor for coronary atherosclerosis, and the risk stratification for coronary atherosclerosis should be based on the presence of proteinuria rather than decreased eGFR within early CKD.