A comparison of neuropsychiatric and cognitive profiles in delirium, dementia, comorbid delirium-dementia and cognitively intact controls.
OBJECTIVE
Delirium and dementia have overlapping features that complicate differential diagnosis. Delirium symptoms overshadow dementia symptoms when they co-occur, but delirium phenomenology in comorbid cases has not been compared to both conditions alone.


METHODS
Consecutive adults with DSM-IV delirium, dementia, comorbid delirium-dementia and cognitively intact controls were assessed using the Revised Delirium Rating Scale (DRS-R98) and Cognitive Test for Delirium (CTD).


RESULTS
Delirium and comorbid delirium-dementia groups had comparable DRS-R98 and CTD total scores, which were greater than in dementia or control groups. On the DRS-R98, multiple non-cognitive symptoms, inattention and disorientation were more severe in delirium groups compared with dementia-alone. Patients with dementia differed from both delirium groups on the CTD test of attention. Spatial span backwards was significantly lower in all patients with cognitive impairment (delirium, comorbid delirium-dementia, dementia alone) compared to controls, whereas spatial span forwards distinguished delirium groups from dementia.


CONCLUSIONS
Delirium phenomenology is similar with or without comorbid dementia. A wide range of neuropsychiatric symptoms distinguish delirium from dementia. Spatial span forward is disproportionately diminished in delirium suggesting usefulness as a differentiating screening test.
Meagher
David J
DJ
University of Limerick Medical School, Limerick, Ireland. david.meagher@ul.ie
Leonard
Maeve
M
Donnelly
Sinead
S
Conroy
Marion
M
Saunders
Jean
J
Trzepacz
Paula T
PT
D000368:Aged; D003071:Cognition / Q000502:physiology*; D003072:Cognition Disorders / Q000209:etiology / Q000523:psychology; D003221:Confusion / Q000523:psychology; D003430:Cross-Sectional Studies; D003693:Delirium / Q000150:complications / Q000523:psychology*; D003704:Dementia / Q000150:complications / Q000523:psychology*; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D011446:Prospective Studies; D013028:Space Perception / Q000502:physiology