Nutrient biomarkers and vascular risk factors in subtypes of mild cognitive impairment: a cross-sectional study.

Abstract

To investigate the interrelationships among blood nutrient biomarkers, the Framingham Stroke Risk Profile (FSRP), and cognitive impairment features in mild cognitive impairment (MCI) subjects and to verify whether nutrient biomarkers and FSRP are risk factors for MCI. According to the criteria for MCI developed by Petersen, 81 subjects aged 50-80 years were divided into a normal control group (NC group, n = 36) and an MCI group (n = 45). Then, the MCI group was divided into an amnestic MCI (a-MCI) and a multidomain MCI (md-MCI) group. All subjects were administered a comprehensive health history to calculate their FSRP score and a thorough neuropsychological assessment of four cognitive domains. Blood samples from all subjects were collected to measure the nutrient biomarkers. FSRP score was not only associated with memory function, but also with executive function, which itself had a negative relationship with eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and total n-3 polyunsaturated fatty acids (n-3PUFAs) levels, and a positive relationship with the ratio of n-6 PUFAs to n-3 PUFAs(n6/n3). Compared with the NC group, the concentrations of EPA, DHA, 25-hydroxy vitamin D (25OHD), and folate and the ratio of n3/n6 in the md-MCI group were significantly lower. In the a-MCI group, only DHA concentrations and the ratio of n3/n6 were significantly lower. After adjustment for potential confounding variables, low education level [Adjusted OR=8.71 (95%CI: 1.83-41.50), p trend = 0.007], decreased plasma 25OHD [Adjusted OR = 4.41 (95% CI: 1.08-17.94), p trend=0.04] and decreased plasma DHA [Adjusted OR = 6.69 (95% CI: 1.37-32.72), p = 0.02] were associated with a higher risk of MCI. Several nutrient biomarkers in MCI patients, especially in md-MCI patients, were lower compared with healthy controls, suggesting that lower 25OHD and DHA levels are risk factors for MCI. However, we found no evidence that FSRP is an early biomarker of MCI.