Table 1.

Differential diagnosis between Alzheimer type dementia and depression.

Characteristics	Major Depressive Episode (MDE)	Alzheimer type Dementia (AD)
Diagnosis	Frequently meets criteria for MDE	Symptoms typically less intense than in MDE
Age at onset	Under or over the age of 60 years	Uncommon at less than 60 years of age
Onset	Typically acute	Insidious
Course	Fluctuations, often with congruent mood	Progressive
Memory complaints	Usually present	Variable
Mood	Depressive	Depressive or euthymic
Sleep-wake cycle	Often changed	Variable
Aphasia/apraxia/agnosia	Uncommon	Manifests as disease progresses
Memory	• Performance better than self-assessment • Performance better with cues for evoking • Intrusion of previously learned information atypical	• Performance worse than self-assessment • No performance improvement with use of cues • Intrusion of previously learned information upon evoking new material
Executive dysfunction	Typical	Variable, occurs later
Processing speed	Slowed	Normal
Effort	Reduces with cognitive demand, disproportionate compromise on more demanding tasks, "don’t know" responses	Usually normal