Cysteine is a better predictor of coronary artery disease than conventional homocysteine in high-risk subjects under preventive medication

• Published in: Nutrition, metabolism, and cardiovascular diseases Vol. 30; no. 8; pp. 1281 - 1288
• Main Authors: Lima, Ana, Ferin, Rita, Fontes, António, Santos, Emília, Martins, Dinis, Baptista, José, Pavão, Maria L.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 24.07.2020
• Subjects: angiography; Azores; biomarkers; blood plasma; Coronary artery disease; cysteine; drug therapy; erythrocytes; homocysteine; Hypercysteinemia; Hyperhomocysteinemia; men; metabolism; mortality; patients; Plasma and erythrocyte aminothiols; Portugal; reversed-phase high performance liquid chromatography; risk factors; thiols; Azores; Portugal; Hypercysteinemia; Hyperhomocysteinemia; Plasma and erythrocyte aminothiols; Coronary artery disease
• ISSN: 0939-4753; 1590-3729; 1590-3729
• DOI: 10.1016/j.numecd.2020.04.010

In Portugal, The Azores Archipelago has the highest standardized mortality rate for CAD. Therefore, the aim of this study was to evaluate conventional risk factors, as well as plasma and erythrocyte aminothiol concentration in high-risk Azorean patients undergoing elective coronary angiography and to investigate whether any aminothiol was associated with CAD risk and severity. 174 subjects with symptomatic CAD (age 56±9y; 68% men) submitted to coronary angiography were split into 2 groups: one formed by CAD patients (≥50% stenosis in at least one major coronary vessel) and the other by non-CAD patients (<50% stenosis). Both groups were age-, sex- and BMI-matched. Plasma and erythrocyte aminothiol profiles were evaluated by RP-HPLC/FLD. CAD patients significantly exhibited both higher concentrations of plasma Cys and hypercysteinemia (Cys ≥ 300 μM) prevalence than those in the non-CAD group (261 ± 58 μM vs. 243 ± 56 μM; 22% vs. 10%, respectively). No differences were observed between groups regarding plasma Hcy levels or hyperhomocysteinemia prevalence. After adjustment for several confounders (including Hcy), subjects in the highest quartile of plasma Cys had a 3.31 (95% CI, 1.32–8.30, p = 0.011) fold risk for CAD, compared with those in the lowest quartiles. Furthermore, plasma Cys levels (but not Hcy) tended to increase with the number of stenotic vessels (1VD: 253 ± 64 μM; 2VD: 262 ± 52 μM; 3VD: 279 ± 57 μM, p = 0.129). Hypercysteinemia revealed to be a better predictor of CAD than hyperhomocysteinemia. Moreover, plasma Cys showed to be a useful biomarker for CAD both in primary and secondary preventions, seeming to resist better than Hcy to oral medication therapy. •The levels of RBC aminothiols did not reflect their content in plasma.•Plasma Cys but not Hcy predict CAD in high-risk subjects under medication.•Plasma Cys levels can also be a useful prognostic CAD marker.•Plasma Cys reduction may be beneficial for management of CAD risk.