DNA damage and plasma total antioxidant capacity in patients with slow coronary artery flow

OBJECTIVES
Although clinical and pathophysiologic features of slow coronary artery flow (SCAF) have been previously described, the underlying pathophysiology has not been fully elucidated. The aim of this study was to investigate the association between DNA damage and SCAF.

STUDY DESIGN
The study was comprised of 23 patients with SCAF and 23 healthy volunteers. DNA damage was assessed by the alkaline comet assay in peripheral lymphocytes and plasma total antioxidant capacity (TAC) was determined by a novel, automated method.

RESULTS
Although DNA damage was higher in the SCAF group than in controls, this did not reach significance (106.6±38.2 AU vs 80.5±51.7 AU; p=0.055). Similarly, TAC levels did not differ significantly between the two groups (1.32±0.32 mmol Trolox equiv./L vs 1.35±0.26 mmol Trolox equiv./L, p=0.667). In the patient group, DNA damage showed a positive correlation with age (r=0.775, p<0.001) and a negative correlation with TAC (r=-0.791, p<0.001) and HDL cholesterol levels (r=-0.456, p= 0.029). In multiple linear regression analysis, TAC and age were found to be independent predictors of DNA damage in patients with SCAF.

CONCLUSION
These findings indicate that SCAF is not associated with increased DNA damage and decreased TAC, suggesting that DNA damage may not be useful in the differential diagnosis of SCAF.