MAPT and Alzheimer disease: There are, however, some concerns about the use of p-tau in clinical settings: an important risk of applying only p-tau markers is the underdiagnosis of non-AD pathologies and other conditions potentially contributing to cognitive disorders in patients with negative results [80]; some factors affect biomarker concentrations such as age, sex [81], and several comorbidities including chronic kidney disease, hypertension, stroke, and myocardial infarction [18], and their impact on the adopted threshold should be established.