The Effect of Effort Test on the Levels of Ischemia Modified Albumin, 7-ketocholesterol and Cholestan-3β , 5α , 6β -triol and their Role in the Diagnosis of Coronary Artery Disease

BACKGROUND: Oxysterols have been shown to play a role in plaque formation while ischemia modified albumin (IMA) is widely accepted as an acute marker for ischemia. The effort test is one of the methods used to identify the presence of coronary artery disease. Thus, there may be a relationship between effort test result and the levels of IMA, 7-ketocholesterol (7-KC) and cholestane-3β,5α,6β-triol (C-triol). METHODS: Thirty patients who underwent effort test and 30 healthy subjects were included in the study. IMA levels were determined with the albumin-cobalt binding test, 7-KC and C-triol levels were determined with LC-MS/MS. Among the patients, two subgroups were identified according to the results of the effort test, group 1 consisted of patients with a positive effort test (n = 12), and group 2 consisted of patients who had a negative effort test (n = 18). RESULTS: 7-KC levels of patients were significantly higher compared to healthy subjects (39.87 ± 2.13 ng/mL, 20.26 ± 1.35 ng/mL; p=0.001). In patients, post-test 7-KC levels were significantly lower than pre-test levels (post-test vs. pre-test: 37.73 ± 2.44 ng/mL vs. 41.07 ± 2.18 ng/mL; p<0.001). There was a significant difference in post-test 7-KC levels among all study groups (negative, positive and healthy: 37.73 ± 2.44 ng/mL, 39.87 ± 2.13 ng/mL, 20.26 ± 1.35 ng/mL, respectively). There was no significant difference in IMA levels. CONCLUSIONS: Patients with positive effort test had significantly higher levels of 7-KC. Additionally, after the effort test, the 7-KC value was reduced. 7-KC is a biomarker of oxidative damage and its value or changes before and after the effort test may be used as a biomarker in the diagnosis and follow-up of coronary artery disease.