Increased lymphocyte deoxyribonucleic acid damage in patients with cardiac syndrome X

OBJECTIVES: To investigate whether there is lymphocyte deoxyribonucleic acid (DNA) damage in patients with cardiac syndrome X (CSX), and its relation with total antioxidant status (TAS), inflammation and ischemia. METHODS: Twenty-three patients with CSX, 21 patients with non-CSX (NCSX) and 20 healthy volunteers were included in the study. Lymphocyte DNA damage (Arbitrary Unit) was assessed by alkaline single cell electrophoresis (comet) assay in peripheral lymphocyte, and plasma levels of TAS (mmol Trolox equiv./l) were determined using a novel automated measurement method. High sensitive C-reactive protein (hsCRP) and other biochemical parameters were measured from all subjects. Treadmill exercise test and coronary angiography were performed to CSX and NCSX groups. RESULTS: Lymphocyte DNA damage was increased in patients with CSX compared with NCSX and control group (p<0.001, for both). Also, TAS was decreased, and hsCRP was increased in CSX compared with NCSX and control group (p<0.001, for all). Lymphocyte DNA damage was correlated with magnitude of ST depression (p=0.034), hsCRP (p=0.001), TAS (p<0.001) and presence of diabetes (p=0.022) in bivariate analysis. In multiple linear regression analysis, lymphocyte DNA damage was correlated with only TAS (beta=-0.413, p=0.017) and hsCRP (beta=0.414, p=0.006). CONCLUSION: Lymphocyte DNA damage was increased in patients with CSX. The increase in lymphocyte DNA damage may be related with increased oxidative stress and inflammation in patients with CSX.