CSF sPDGFRβ and tau were significantly lower in B/AA than NHW.<h4>Discussion</h4>Vascular dysfunction and neuroinflammation may precede cognitive decline and disease pathology in the very early preclinical stages of AD, and there are race-related differences in these relationships.<h4>Highlights</h4>Cerebrospinal fluid (CSF) Alzheimer's disease (AD) biomarkers changed over 2 years in high-risk middle-aged adults. The gene discussed is MAPT; the disease is early-onset autosomal dominant Alzheimer disease.