Diagnosis-Independent Cerebrospinal Fluid Biomarkers of Alzheimer Disease

Low amyloid-beta_1-42 (Aß1-42), high total tau, and high phosphorylated tau_181P (P-tau181P) in the cerebrospinal fluid (CSF) have been associated with Alzheimer disease (AD). Because clinical diagnosis often occurs years after the start of the AD pathological process, these authors created a model to identify cutoff levels of these CSF biomarkers for use in preclinical diagnosis. They based their model on data from 114 cognitively normal people, 196 people with mild cognitive impairment (MCI), and 100 people with AD who underwent lumbar puncture and clinical follow-up as part of the well-characterized Alzheimer's Disease Neuroimaging Initiative (ADNI) database. The authors verified their findings in two independent, smaller data sets: 68 pat…