A new study distinguishes between two distinct phases of Alzheimer's disease: an early, 'stealth' one without symptoms, and a second phase that aggressively damages the brain.

Alzheimer's disease might damage the brain in two distinct phases, a new study suggests. An early phase that occurs slowly and silently appears to lay the groundwork for a second, more widely destructive phase of Alzheimer's, according to sophisticated brain scans.

"The results fundamentally alter scientists' understanding of how Alzheimer's harms the brain," researchers say.

An analysis of the genetic activity of brain cells in individuals who have died with Alzheimer's disease has revealed the condition progresses in two stages; a slow increase in inflammation, followed by a more rapid degeneration.

New research reveals Alzheimer’s disease may damage the brain in two distinct phases, offering new insights for diagnosis and treatment.