The strategy of using theratio between two proteins of the plasmin-BDNF pathway in serum hasalso been adopted in people affected by different mental disorders.The results demonstrated that the combination of multiple serum proteinlevels in this pathway was better than any single protein measurementin accuracy of diagnosis and differentiation of such disorders.52,53 Our results suggest that also in Alzheimer, the use of the ratioPAI-1/BDNF could be useful as a diagnostic marker of dementia whencompared to single measurements of these two proteins. This evidence concerns the gene BDNF and psychiatric disorder.