GFAP and spinal muscular atrophy, type 1: Initially at baseline, Type 1 SMA patients showed significantly high levels of NFL (4598 ± 981 pg/mL vs. 148 ± 39 pg/mL; p = 0.001), tau (939 ± 159 pg/mL vs. 404 ± 86 pg/mL; p = 0.02), and GFAP (236 ± 44 pg/mL vs. 108 ± 26 pg/mL; p = 0.02) compared to controls.