‘Beyond amyloid’ outlines recent challenges to the amyloid cascade hypothesis of Alzheimer’s disease. This theory’s enduring popularity has not been matched by success in the clinic. Some people without dementia appear to have high amyloid levels and some brain-injured patients with more amyloid have better outcomes than those with less. One possible explanation is that neurodegeneration begins long before symptoms appear. Other theories include amyloid as the defence rather than cause, and the idea of an immune response to infection causing inflammation in the brain. All this points towards the importance of method and the acknowledgement of the roles played by other parts of the body and lifestyle factors.
