MAPT and Cognitive impairment: As previously indicated by Schrag et al. (2017), we also found UPSIT (HR: 0.945, CI: 0.894–0.999, Wald: 4.014, P = 0.045) and amyloid-β:tau (HR: 202.716, CI: 5.870–7000.656, Wald: 8.640, P = 0.003) to be significant predictors of cognitive impairment in the Cox survival analysis with all parameters as covariates.