[Correlation network of metabolic indicators in cognitive impairment and normal aging in the elderly]

To conduct a comparative assessment of metabolic, hematological, and antioxidant parameters in the peripheral blood of cognitively intact elderly individuals versus patients experiencing mild cognitive impairment, as well as to establish the correlations among the studied metrics within the respective groups.

The cross-sectional cohort study included 172 outpatients aged 60 years and older, who were assessed at the V.M. Bekhterev National Medical Research Center for Psychiatry and Neurology. Two groups were established: one comprising patients with mild cognitive impairment (n=118) and another with cognitively intact individuals (n=54). Participants underwent clinical and neuropsychological assessments, as well as magnetic resonance imaging of the brain. A laboratory examination of fasting venous blood was performed, encompassing evaluations of hematological and biochemical parameters, antioxidant enzyme activities, and the profile of polyunsaturated fatty acids using gas chromatography. Non-parametric comparison methods and correlation analyses were applied (p≤0.05).

The findings indicated that patients with mild cognitive impairment exhibited a statistically significant reduction in the activities of superoxide dismutase (1412 IU/g of Hb and 1512.98 IU/g of Hb, respectively; p=0.048), catalase (7.17 IU/mL and 9.03 IU/mL; p<0.001), and glutathione peroxidase (47.81 IU/mL and 69.22 IU/mL of erythrocyte suspension; p<0.001). Additionally, the concentrations of eicosapentaenoic acid (3.10 μg/mL and 4.20 μg/mL; p=0.004) and docosahexaenoic acid (8.85 μg/mL and 11.80 μg/mL; p=0.005) were notably decreased. Correlation analysis revealed an increase in intersystemic relationships among lipid metabolism, the antioxidant system, and hematological parameters, alongside a decrease in intrasystem correlations compared with the cognitively intact group.

The study results suggest that mild cognitive impairment is associated with initial signs of metabolic dysregulation and a reorganization of metabolic system integration. These findings may be significant for stratifying risk associated with cognitive impairment.