Dietary and Serum Level of Antioxidants in the Elderly with Mild Impaired and Normal Cognitive Function: A Case-Control Study

Background: Antioxidants are considered essential components in neurodegenerative disease management since they can protect cells from oxidative damage. Objectives: The current study aimed at evaluating the intake and serum level of selected antioxidants in subjects possessing mild cognitive impairment (MCI) compared with a cognitively intact control. Methods: The current prospective, case-control study was conducted in Tabriz from December 2016 to August 2017 on a total of 45 patients with MCI as a case group and another 45 healthy subjects matched by age and gender were recruited for the control group. After completing the mini-mental state examination (MMSE-12) questionnaire, the cases with MCI were identified using the modified Peterson standard. By a semi-quantitative food frequency questionnaire (FFQ), the common dietary intakes during the previous year were recorded and blood samples were collected. Results: Of the 90 subjects in the current study, 61% were male and 39% female, with the mean age of 68.85.5 years. There were no significant differences between the two groups with respect to dietary intakes of vitamin C, beta-carotene, and lycopene (P = 0.079, P = 0.413, and P = 0.455, respectively). The results of the studied parameters showed that serum beta-carotene and lycopene (P = 0.004 and P = 0.044, respectively) in healthy subjects were significantly higher than those of the elderly people with MCI. There was a significant correlation between Vitamin C dietary intake and serum level and cognitive scores in MMSE-12 (r = 0.231, P = 0.028 and r = 0.224, P = 0.033, respectively) and also between serum level of lycopene and cognitive scores(r = 0.388, P = 0.000). Conclusions: The subjects with mild cognitive impairment had a significantly lower serum levels of lycopene beta-carotene antioxidants compared with healthy subjects, and there was a positive correlation between serum level of vitamin C and lycopene and also vitamin C dietary intake and scores in the MMSE-12 test.