TGFB1 and Mental deterioration: Therefore, we examined the association between the plasma concentrations of TGF-β1 at baseline (T0) to the rate of cognitive decline (T1), and we found that the lower plasma TGF-β1 concentrations at T0 strongly predicted the following cognitive decline evaluated by the TSI score at 12 months in individuals with DS, suggesting that TGF-β1 should be further explored as a potential plasma marker able to predict the following cognitive decline in the DS population.