MAPT and Neurofibrillary tangles: Another important finding of this study is that while AD neurofibrillary tangle pathology (Braak score < 2 [31]) was present in 17% of the FTLD-Tau and 24% of the FTLD-TDP patients, stepwise regression showed that AD comorbidity was not a good predictor of TDP-43 burden and was therefore excluded from the final model.