Serum concentration of dihomo-γ-linolenic acid is associated with cognitive function and mild cognitive impairment in coronary artery disease patients

Background: The relation between levels of n-6 polyunsaturated fatty acids (PUFAs) and cognitive function and mild cognitive impairment (MCI) in patients with coronary artery disease (CAD) is unclear. The purpose of the present study was to examine the associations between levels of n-6 PUFAs and cognitive function and MCI in patients with CAD. Methods: We conducted a cross-sectional study of 129 patients with CAD but without probable dementia. MCI was estimated with the Japanese version of the Montreal Cognitive Assessment (MoCA-J). We classified patients into the normal cognitive group and MCI group and compared their clinical characteristics and serum levels of PUFAs. The relation between these levels and cognitive function and MCI was clarified with Pearson correlation analysis and logistic regression analysis. Results: The serum levels of dihomo-gamma-linolenic acid (DGLA) in the CAD patients with MCI were significantly lower than those in the patients with normal cognitive function (p= 0.04). The serum levels of DGLA were positively associated with the MoCA-J score (r = 0.24, p= 0.005) and significantly associated with MCI in the univariate logistic regression analysis (odds ratio, 0.97; p= 0.035). However, in the multivariate logistic regression analysis, only age was significantly associated with MCI (odds ratio, 1.11; p < 0.001). Conclusions: The serum levels of DGLA were associated with cognitive function and MCI in patients with CAD. Although not an independent predictor, DGLA might be one useful marker with which to identify early cognitive decline in these patients.