Reduction of Amyloid-ß Plasma Levels by Hemodialysis: An Anti-Amyloid Treatment Strategy?

ABSTRACT

BACKGROUND: Cognitive impairment in hemodialysis patients is common, but the underlying pathogenesis remains unclear. Alzheimer's disease is the most common cause of dementia in the general elderly population. Histopathological hallmarks are, among others, senile plaques, which consist of amyloid-ß (Aß). OBJECTIVE: To measure plasma levels of Aß42 and Aß40 during hemodialysis and to examine potential associations with cognitive performance in cognitively impaired hemodialysis patients. METHODS: Plasma samples of 26 hemodialysis patients were collected shortly before, after 50% of dialysis time, and at the end of a dialysis session. Aß42 and Aß40 levels were measured by a high-sensitivity ELISA for human amyloid-ß. Cognition was tested under standardized conditions using the Montreal Cognitive Assessment (MoCA) as proposed previously. RESULTS: Clearance rates of both peptides during one dialysis session were 22% and 35% for Aß42 and Aß40, respectively. Aß42 but not Aß40 baseline levels were significantly associated with MoCA test results (r = 0.654, p = 0.001). CONCLUSION: In cognitively impaired hemodialysis patients plasma Aß42 levels were associated with cognitive performance and both Aß42 and Aß40 plasma levels could be effectively reduced by dialysis. By inducing peripheral Aß sink, hemodialysis may be considered as an anti-amyloid treatment strategy.