The Correlation Between Serum Calcium, Phosphorus Levels And Coronary Artery Calcification In The Population Without Chronic Kidney Disease

Objective:To explore the correlation between serum calcium (Ca), phosphorus (P) levels and coronary artery calcification and stenosis in the population without chronic kidney disease and further discuss the significance of these biochemical indicators in clinical practice.Methods:We collected clinical data of 881 inpatients in the second affiliated hospital of Chongqing Medical University from January 2013 to June 2014 and analyzed the correlation between serum Ca, serum P, calcium-phosphorus product (CPP) and coronary artery calcification and coronary stenosis retrospectively.Results:There were 403(46%) patients with coronary artery calcification and 163(19%) patients with stenosis of at least one artery of ≥50% severity. The mean serum Ca levels of patients with and without coronary calcification were 8.95 mg/dL and 9.02 mg/dL respectively (P= 0.013), serum P levels were 3.53 mg/dL and 3.47 mg/dL respectively (P= 0.082), CPP were 31.7 mg2/dL2 and 31.3 mg2/dL2 respectively (P= 0.323). There were no significant differences in the serum Ca, P and CPP levels of patients with coronary stenosis ≥50% or stenosis <50%. Agaston score> 100 holded high sensitivity (65%) and specificity (93%) to predict coronary stenosis ≥50%. Subgroup analyzes of serum Ca, P, and CPP indicated that there was significant positive correlation between increasing serum Ca levels and coronary artery calcification (CACS> 100) compared to lower Ca level (～8.6 mg/dL), Ca:8.7-8.9 mg/dL (OR:1.68, P=0.045); Ca:9.0～9.3 mg/dL (OR:1.69, P= 0.047); Ca:9.4～mg/dL (OR:1.89, P=0.048). However there was no significant correlation between serum P、CPP and coronary calcification (CACS> 100). Similar negative relationship was also observed between various Ca, P, CPP levels and coronary stenosis≥50%.Conclusion:The study suggested that increasing serum Ca had positive correlation with coronary calcification (CACS> 100) and high blood Ca levels might be a risk factor for coronary calcification.