Clinical course of Alzheimer’s disease

Alzheimer’s disease (AD) is an age-related neurodegenerative disorder, with onset usually in late life, characterized by progressive cognitive impairment, a variety of behavioural symptoms, and impairment in the activities of daily living. The initial symptom in typical AD is episodic memory loss, which reflects hippocampal dysfunction. The memory deficits are very characteristic with low recall performance despite retrieval facilitations with cueing. These initial deficits can be identified by appropriate cognitive tests. Behavioural symptoms can be present at early stages of the disease (even in pre-clinical states), although the frequency increases as the disease progresses. In the past decade there has been a growing interest in characterizing these pre-clinical and prodromal stages as treatments are expected to be more effective in these phases.