- Alzheimer’s disease is the most common cause of dementia in the elderly. More than 5% of ≥70 year old persons in the world are affected from AD.
- AD most commonly presents with an insidious onset of memory loss followed by slowly progressing dementia over several years.
- Pathologically, atrophy is distributed throughout the medial temporal lobes, medial and lateral parietal lobes (temporo-parietal distribution) as well as, lateral frontal cortex.
- Microscopically, there are neuritic plaques containing neurofibrillary tangles (NFT) composed of hyperphosphorylated tau proteins and accumulation of amyloids in blood vessel walls of cortex and leptomeninges.
- Brain scan is useful in diagnosing AD.