Reduction of Amyloid-β 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-β (Aβ).

Objective:

To measure plasma levels of Aβ₄₂ and Aβ₄₀ 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. Aβ₄₂ and Aβ₄₀ levels were measured by a high-sensitivity ELISA for human amyloid-β. 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 Aβ₄₂ and Aβ₄₀, respectively. Aβ₄₂ but not Aβ₄₀ baseline levels were significantly associated with MoCA test results (r = 0.654, p = 0.001).

Conclusion:

In cognitively impaired hemodialysis patients plasma Aβ₄₂ levels were associated with cognitive performance and both Aβ₄₂ and Aβ₄₀ plasma levels could be effectively reduced by dialysis. By inducing peripheral Aβ sink, hemodialysis may be considered as an anti-amyloid treatment strategy.