The GPX1 rs1050450 c.593 TT (p.198 Leu/Leu) genotype tended to be associated with the lowest frequency of cognitive impairment, compared to the c.593 CC (p.198 Pro/Pro) and c.593 CT (p.198 Pro/Leu) genotypes; notably, none of the individuals with the TT genotype presented with psychotic symptoms. This evidence concerns the gene GPX1 and Cognitive impairment.