APOE and Cognitive impairment: Since previous research indicated the necessity to control forthe well-known “risk” factor of developing cognitive deficit(APOE ε4 variant) in the statistical models (Porter et al., 2018;Li X. et al., 2019), the hypothesis suggested in the presentstudy was examined in both total sample and in the groupssplit by the presence of APOE ε4 allele.