Table 1.

Summary of the comparison between the three forms of AD.

	LOAD	ADAD				DSAD
Clinical Features
Mean age of onset	80.2 ± 6	PSEN1	PSEN2	APP	dAPP	55.8 ± 6.29
		43.3 ± 8.6	58.1 ± 9.5	47.6 ± 7.1	51.5 ± 5.3
Mean age of death	86.1 ± 7.04	50.5 ± 9.7	71.8 ± 10.6	58 ± 8.4	60.4 ± 6.2	59.98 ± 5.98
Cerebral Amyloid Angiopathy	Low	High (with higher prevalence in dAPP)				High
Amnestic phenotypes	Early episodic memory loss Early loss of visuoperceptual skills Attention deficits Language deterioration	Early episodic memory loss Late loss of visuoperceptual skills Attention deficits Language deterioration (depending on the particular mutation)				Early episodic memory loss Early loss of visuoperceptual skills Attention deficits Language deterioration Decline in functional skills
Non amnestic phenotypes (e.g: behavioural changes and executive dysfunction)	Less Common	More Common				More Common
Neurological symptoms (e.g: epilepsy, myoclonus, spastic paraparesis, cerebellar signs)	Less Common	More Common				More Common
Neuroimaging and Neuropathology
Altered default mode connectivity	Present	Present				Present
Biochemical changes	Similar in magnitude and direction	Similar in magnitude and direction				Similar in magnitude and direction
Aβ deposition map	Similar	Similar				Similar
Initial Striatal Aβ	Absent	Present				Present
Hypometabolism map	Similar	Similar				Similar
Atrophy map	Similar	Similar (but accelerated)				Similar
Distribution of tau	Similar	Similar				Similar
CO-PATHOLOGIES
Lewy body pathology	Common	Most common				Rare
TDP-43 Pathology	More common Similar distribution	Less Common Similar distribution				Less Common Similar distribution

AD, Alzheimer’s disease; LOAD, Late-onset Alzheimer’s disease; ADAD, Autosomal Dominant Alzheimer’s disease; DSAD, Down syndrome-associated Alzheimer’s disease.