This is not a diagnosis, it is more a symptom complex comprising progressive impairment of memory and intellect with or without personality or behavioural change. It is important to try and establish a cause if possible.

The three major categories of dementia are Alzheimer's disease, vascular (blood vessel-related) dementia and diffuse Lewy body disease.

Investigations include a blood screen, chest x-ray, MR Imaging of the brain, neuropsychometry (measurement of cognition & memory), occasionally spinal fluid examination and EEG.

There are currently four drugs commonly used in Alzheimer's disease. There will be more shortly.