Background: Cardiovascular disease is the leading cause of mortality and morbidity among patients with chronic kidney disease. This is attributed not only to traditional, but also non-traditional risk factors, of which the altered calcium-phosphorus homeostasis is of interest in this study. A recently studied tool in evaluating the degree of coronary artery complexity in patients who have undergone coronary angiography is the Synergy Between PCI With Taxus and Cardiac Surgery (SYNTAX) score.

Objective: This study aimed to determine if the serum calcium and phosphorus are correlated with the SYNTAX score in patients with CKD stages III, IV and V

Materials and Methods: This is a retrospective correlation study, which included 79 patients with CKD stages III, IV, V not on dialysis and on dialysis, who have undergone invasive coronary angiography at the National Kidney and Transplant Institute (NKTI) Catheterization Laboratory. The SYNTAX score was computed via an interactive web program with the help of an interventional cardiologist. This score was then correlated with serum calcium and phosphorus using Pearson’s Correlation Test.

Results: Among the 79 subjects included in the study, 7.6% are at Stage III, 11.4% at Stage IV, 5.1% at Stage V but not yet on dialysis, and 75.9% are on dialysis. A statistically significant inverse correlation was noted between SYNTAX score and total EGFR (R coefficient -0.230, p-value 0.04). But when analyzed per stage of CKD, there was no statistically significant correlation. There were positive but weak correlations between the SYNTAX score and the serum calcium (R coefficient 0.135, p-value 0.231) and phosphorus values (R coefficient 0.044, p-value 0.696) but these were not statistically significant.

Conclusion: Among CKD Stages III, IV, V and dialysis patients, there is a positive but weak and insignificant correlation between the SYNTAX score and the levels of calcium, and phosphorus. A robust and equal number of cases among the different stages of CKD have to be analyzed in order to generate statistically significant data with regards the correlation of declining kidney function and the SYNTAX score.

Keywords: SYNTAX score, Coronary artery complexity, Coronary angiography, Chronic kidney disease, EGFR

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