depressive pseudodementia

Epidemiology

• 10% of late-onset depression

Clinical manifestations

• affective symptoms &/or a history of prior depression
• discrete course with subacute onset
• mini-mental status exam > 21 & 'depressed' depression scale
• patient emphasizes cognitive deficits & disability
• more comparable* recent & remote memory loss
• more comparable* impairment of verbal & performance skills
• normal neurologic examination
• features of subcortical dementia
  • psychomotor retardation
  • apathy
• insomnia
• anorexia

* compared with dementia

Diagnostic procedures

• normal P300 scalp-recorded potentials
• EEG: minor abnormalities in 20%
• neuropsychologic testing (best discriminitory tests from dementia)
  • delayed retrieval > immediate recall
  • tasks with distraction before retrieval
  • tasks with high capacity demand
  • tasks presenting words or common objects > tasks presenting sentences, digits or geometric designs

Radiology

normal neuroimaging

Management

• antidepressants result in improvement rather than delirium
• diagnostic maneuvers
  • sleep deprivation 36-40 hours may result in transient improvement
  • amobarbital interview
    • marked improvement with pseudodementia
    • all deficits worse with dementia

More general terms

• depression

Additional terms

• dementia; Alzheimer's disease & related dementias (ADRD)