ABSTRACT

The risk of developing dementia increases with age, occurring in one in six people over the age of 80 years. Alzheimer’s disease (AD) is the most common dementia, making up about 60% of cases.

■ Two main types of symptoms have been a focus of treatment in dementia and related disorders: – Cognitive deficits – Non-cognitive features (behavioural and psychological symptoms

of dementia [BPSD], consisting of affective, psychotic and behavioural disturbances)

■ Deficits in the acetylcholine (ACh) system in AD led to a focus on drug approaches to enhance ACh function: – Initial studies with ACh precursors did not show benefit. – Acetylcholinesterase inhibitors (AChEIs): Tacrine introduced as a

cognitive enhancer in AD in the 1980s and licensed for AD in 1993 (United States).