All statistical analyses were performed using SPSS 17.0. Depending on the scale properties of the data, mean and standard deviation or frequencies and percentages are provided. Univariate group differences were evaluated by means of t-tests/Mann & Whitney U-Test or Fisher exact tests, and MANOVA models were used to evaluate multivariate group differences with Wilk's-being reported. Multiple correlations between the sets of psychological parameters and the biomarkers BDNF and IGF were performed exploratively. All statistical analyses were conducted at a significance level of 5%; due to the large number of comparisons and to reduce the risk of an inflation of the error type I the significance level will be adjusted to 2.5‰ (Bonferroni-Holm adjustment of error type I) when discussing the results. For the follow-up evaluation, sample sizes of n=41 patients per group are aimed at to achieve the detection of group differences in the percentage of cognitive impairment; this will make it possible to prove differences in percentages for median up to large effects (H>.50) at a level of significance of 5% and a power of 80%.