The performance of plasma p‐tau217 in Black middle‐aged and older adults
Gilda E. Ennis, Derek Norton, Rebecca L. Koscik, Diane C. Gooding, Fabu P. Carter, Rachael E. Wilson, Megan Zuelsdorff, Shenikqua Bouges, Sanjay Asthana, Sterling C. Johnson, Henrik Zetterberg, Carey E. Gleason
Abstract
INTRODUCTION: Medical conditions prevalent in Black adults within the United States have been associated with plasma tau phosphorylated at threonine 217 (p-tau217); however, insufficient p-tau217 research has been conducted with Black adults. METHODS: Participants included n = 233 predominantly cognitively unimpaired adults enrolled in the African Americans Fighting Alzheimer's in Midlife study. Subsamples had creatinine (n = 137) and positron emission tomography (PET; amyloid-PET = 65 [amyloid-PET-positive = 16/65]; tau-PET = 70). We tested whether p-tau217 (ALZPath, Inc.) varied by medical condition and amyloid- and tau-PET-positivity status and assessed the diagnostic accuracy of p-tau217. RESULTS: ): eGFR <60 group = 0.48, CVD = 0.25, amyloid-PET-positive status = 0.54; tau-PET-positive status = 0.56. Lower eGFR was related to higher p-tau217 when adjusting for amyloid-PET. For abnormal amyloid-PET and tau-PET, p-tau217 exhibited areas under the curve of 0.90 and 0.89, respectively. DISCUSSION: Plasma p-tau217 showed promise as an Alzheimer's biomarker in Black adults; however, kidney function and CVD should be considered when interpreting levels. HIGHLIGHTS: Plasma tau phosphorylated at threonine 217 (p-tau217) was tested in a sample of Black middle-aged and older adults. Level of p-tau217 was higher in impaired kidney function and cardiovascular disease. Obesity and diabetes were not related to p-tau217. Level of p-tau217 was higher in amyloid- and tau-PET-positive status. Plasma p-tau217 showed good receiver-operating characteristic area under the curve for abnormal amyloid- and tau-PET.