While Spp1 concentrations seemed to be slightly higher in patients with ALS (23.08 [15.85–30.65] ng/mL) than in SBMA patients (20.90 [16.18–29.53] ng/mL) and healthy controls (20.46 [13.80–25.90] ng/mL), the differences were not significant (p = 0.22; Table 2). Here, SPP1 is linked to Kennedy disease.