2021 Volume 38 Issue 3 Pages 337-342
The number of dementia patients is rapidly increasing worldwide, however, in some cohorts in western countries the number shows a decreasing trend oppositely. The initial trial for disease modifying drug has started in 1999 by Schenk et al., but in vail for a long duration. The obstacles to be overcome appear to be an accurate diagnosis of dementia other than Alzheimer's disease, as well as autoimmune encephalitis and a similar but milder condition named amyloid–related imaging abnormalities (ARIA). When the diagnosis of Alzheimer's disease is delayed, accumulated fibrillary amyloid may be degraded and result in ARIA as a perivascular edema and microhemorrhages after administration of anti–amyloid β (Aβ) antibodies. Therefore, an early diagnosis of Alzheimer's disease is pivotal for safe and efficient strategies for disease modifying drugs.
At present, amyloid PET study and cerebrospinal fluid (CSF) Aβ42 levels are an established biomarker for early diagnosis of Alzheimer's disease. These biomarkers still have drawbacks because of high cost and invasiveness, respectively. However, more recently, peripheral blood biomarkers have been introduced. Moreover, novel findings on aggregation mechanism of anti Aβ has been revealed, thereby accelerating development of disease modifying drug for Alzheimer's disease.