Traumatic brain injury and Alzheimer's disease: The null hypothesis wins.

Abstract

The theory that traumatic brain injury initiates Alzheimer's disease owes much of its existence to classical studies on boxers. It now appears that both the complexity of postmortem neuropathology and the clinical syndrome were not fully appreciated. Large scale studies linking epidemiology and biology continue to show that chronic effects of traumatic brain injury and Alzheimer's disease pathophysiology are biologically distinct. Researchers are encouraged to look beyond conventional protein precipitates for explanations of clinical deterioration following traumatic brain injury.