Background: Biomarkers of oxidative stress have been associated with cognitive status in humans and have been proposed to guide prognosis/treatment in Alzheimer's disease (AD) and mild cognitive impairment (MCI).
Objective: The aim of this study was to compare oxidative stress status in the plasma of mild-moderate AD, MCI, and healthy elderly with normal cognition (HE) undergoing a non-pharmacological intervention including multi-modal cognitive training ("My Mind Project").
Methods: A prospective randomized trial involving 321 elderly people enrolled in Marche Region, Italy. Each subject was randomly assigned to an experimental (cognitive training) or to a control group. Cognitive performances and biomarkers have been analyzed before intervention (baseline), immediately after termination (follow-up 1), after 6 months (follow-up 2), and after 2 years (follow-up 3). The biological antioxidant potential (BAP) to Diacron reactive oxygen metabolites (d-ROM) ratio has been used as an indicator of oxidative stress status and as outcome variable.
Results: We have found no differences in the oxidative status among AD, MCI, and HE. Neither did we find a significant effect of the intervention within experimental groups. Gender was the sole factor with a strong significant effect on BAP/d-ROM.
Conclusions: Based on these results, the utility of biomarkers of oxidative stress to guide prognosis/treatment in AD or MCI seems to be limited by lack of specificity, large interindividual variability, and gender bias.
Keywords: Aging; Alzheimer’s disease; cognitive dysfunction; oxidative stress.