IL1B and supranuclear palsy, progressive, 1: Further multivariate linear regression revealed positive correlations of total tau with IL-6 (β = 0.346, p = 0.014) and IL-1β (β = 0.312, p = 0.028), and of p-tau181 with IL-1β (β = 0.379, p = 0.008) in patients with PSP (Figure 2J and Supplementary Table 4).