Effects of glomerular filtration rate on the severity of coronary heart disease

OBJECTIVE
Chronic kidney disease (CKD) is considered to be one of the most common risk factors for cardiovascular diseases. Glomerular filtration rate (GFR) is the best method of testing level of kidney function and determining stage of kidney disease. The aim of this study was to examine the impact of renal function on severity of coronary heart disease (CHD).

METHODS
The present study included 918 patients undergoing elective coronary angiography. GFR was evaluated by simplified Modification of Diet in Renal Disease (MDRD) formula (mL/min/1.73 m2). The extent and severity of CHD were evaluated according to SYNTAX score.

RESULTS
According to SYNTAX score, 416 patients had normal coronary arteries or nonsignificant CHD (control group), 267 had mild CHD (SYNTAX score: 1–22), 129 had moderate CHD (SYNTAX score: 23–32), and 106 had severe CHD (SYNTAX score: ≥33). Estimated GFR values (median [25th– 75th percentiles]) were 99.00 (83.00–116.00) in the control group, 85.00 (73.00–101.00) in the mild CHD group, 87.00 (73.25–101.75) in the moderate CHD group, and 81.00 (65.00–101.00) in the severe CHD group. According to Spearman’s rank correlation analysis, a negative correlation found between MDRD and SYNTAX score was statistically significant (p<0.001, r=-0.268).

CONCLUSION
Renal function is an important predictor of presence and severity of angiographic CHD in patients without severe renal impairment. Negative correlation between MDRD and SYNTAX score was determined. This simple biochemical test can be used in determining risk of cardiovascular disease aside from other risk factors during routine clinical practice.