TARDBP and frontotemporal dementia: Analysis of the serum TDP-43 levels in the total group of the FTD patients (N = 254) vs. the HC group (N = 105) indicated that the levels were significantly lower in the FTD patients compared to HC (275.3 pg/mL vs. 361.8 pg/mL, B = 0.181, 95%CI = 0.014–0.348, p = 0.034) when adjusted for age and gender (Table 1).