A comparison of p‐tau assays for the specificity to detect tau changes in Alzheimer's disease

Increases in plasma phosphorylated tau (p-tau) in amyotrophic lateral sclerosis (ALS) versus controls were significantly smaller for low-molecular-weight (LMW)-specific p-tau assays (i.e., p-tau217Lilly, p-tau181Lilly) compared with p-tau assays that also detect high-molecular-weight (HMW) assays (i.e., p-tau217AlzPath, p-tau181UGOT). The LMW-specific p-tau assays showed significantly larger increases in plasma p-tau in AD versus ALS compared with the non-specific assays. The LMW-specific p-tau assays discriminated AD from ALS with higher precision, showing significantly better performance than the non-specific assays. LMW-specific p-tau assays could be more useful in the diagnostic workup of AD, especially in population-based communities where conditions causing peripheral neuropathy (such as ALS) are frequent.