RESUMEN
BACKGROUND: A recently developed global indicator of oxidative stress (OXY-SCORE), by combining individual plasma biomarkers of oxidative damage and antioxidant capacity, has been validated in several pathologies, but not in left ventricular hypertrophy (LVH). The aim of this study was to design and calculate a plasma oxidative stress global index for patients with LVH. METHODS: A total of 70 consecutive adult patients were recruited in our institution and assigned to one of the two study groups (control group/LVH group) by an echocardiography study. We evaluated plasmatic biomarkers of oxidative damage (malondialdehyde and thiolated proteins) and antioxidant defense (total thiols, reduced glutathione, total antioxidant capacity, catalase, and superoxide dismutase activities) by spectrophotometry/fluorimetry in order to calculate a plasma oxidative stress global index (OXY-SCORE) in relation to LVH. RESULTS: The OXY-SCORE exhibited a highly significant difference between the groups (p < 0.001). The area under the receiver operating characteristic curve was 0.74 (95% confidence interval (CI), 0.62-0.85; p < 0.001). At a cut-off value of -1, the 68.6% sensitivity and 68.6% specificity values suggest that OXY-SCORE could be used to screen for LVH. A multivariable logistic regression model showed a positive association (p = 0.001) between OXY-SCORE and LVH [odds ratio = 0.55 (95% CI, 0.39-0.79)], independent of gender, age, smoking, glucose, systolic and diastolic arterial pressure, dyslipidemia, estimated glomerular filtration rate, body mass index, and valvular/coronary disease. CONCLUSION: OXY-SCORE could help in the diagnosis of LVH and could be used to monitor treatment response.
RESUMEN
BACKGROUND: Left ventricular hypertrophy (LVH) has been associated with oxidative stress, although not with the protein thiolation index (PTI). This study explored the potential use of PTI as a biomarker of oxidative stress in patients with LVH. METHODS: We recruited 70 consecutive patients (n = 35 LVH and n = 35 non-LVH) based on an echocardiography study in our institution (left ventricular mass indexed to body surface area). Plasma levels of both S-thiolated protein and total thiols were measured as biomarkers of oxidative stress by spectrophotometry, and PTI was calculated as the molar ratio between S-thiolated proteins and the total thiol concentration. RESULTS: Values for plasma S-thiolated proteins were higher in patients with LVH than in the control group (P = 0.01). There were no differences in total thiols between the LVH group and the control group. Finally, PTI was higher in patients with LVH than in the control group (P = 0.001). The area under the ROC curve was 0.75 (95% CI, 0.63-0.86; P<0.001), sensitivity was 70.6%, and specificity was 68.6%, thus suggesting that PTI could be used to screen for LVH. A multivariable logistic regression model showed a positive association (P = 0.02) between PTI and LVH (OR = 1.24 [95% CI, 1.03-1.49]) independently of gender (OR = 3.39 [95% CI, 0.60-18.91]), age (OR = 1.03 [95% CI, 0.96-1.10]), smoking (OR = 5.15 [95% CI, 0.51-51.44]), glucose (OR = 0.99 [95% CI, 0.97-1.01]), systolic arterial pressure (OR = 1.10 [CI 1.03-1.17]), diastolic arterial pressure (OR = 0.94 [CI 0.87-1.02]), dyslipidemia (OR = 1.46 [95% CI, 0.25-8.55]), estimated glomerular filtration rate (OR = 0.98 [95% CI, 0.96-1.01]), body mass index (OR = 1.03 [95% CI, 0.90-1.10]), and valvular and/or coronary disease (OR = 5.27 [95% CI, 1.02-27.21]). CONCLUSIONS: The present study suggests that PTI could be a new biomarker of oxidative stress in patients with LVH.
