Dementia Japan36:76-81, 2022

SNAP（suspected non-Alzheimer disease pathophysiology）: biomarker, underlying pathology and clinical implication

Takeshi Ikeuchi

Department of Molecular Genetics Brain Research Institute, Niigata University

Recent advance in biomarker development has enable to estimate the underlying pathological changes occurring in brain of patients with dementia.　SNAP （suspected non-Alzheimer disease pathophysiology） is a biomarker derived concept that is defined by normal biomarker for amyloid-β deposition and abnormal biomarker for neurodegeneration.　Subjects with SNAP biomarker signature at preclinical Alzheimer’s disease and mild cognitive dementia stages have increased risk for progression to dementia.　SNAP is composed of heterogeneous neurodegenerative disorders.　In particular, PART （primary age-related tauopathy） and LATE （limbic predominant age-related TDP-43 encephalopathy） have been recently paid much attention as a major cause of SNAP presenting with amnestic dementia.　Understanding of underlying etiologies of SNAP will become more important for the clinical practice of dementia.

Address correspondence to Dr. Takeshi Ikeuchi, Department of Molecular Genetics, Brain Research Institute, Niigata University （1-757 Asahimachi, Niigata 951-8585, Japan）