TGFB1 and Dravet syndrome: Interestingly, we found that lower TGF-β1 plasma concentrations at T0 were strongly correlated with the cognitive decline assessed by the TSI score at T1 (12 months) in individuals with DS (Figure 3, Spearman r 0.4427, p < 0.01), suggesting that a decline in TGF-β1 plasma concentrations could be associated with cognitive decline in adult individuals with DS.