 Patients in whom the difference worsening in the global score at 3 months to the global score at baseline will be greater than 2 standard deviations from the expected difference, i.e., the mean difference between the two evaluations baseline and 3 months observed in the Control Group, will be diagnosed with POCD. Moreover, changes in raw scores of the different tests will be considered with the purpose of identifying possible changes in specific cognitive domains. 