Objective: The aim of this study was to examine whether delirium has specific clinical subtypes.
Method: One hundred and eighty-three elderly subjects meeting DSM-IIIR criteria for delirium were evaluated using a 19-item symptom check-list assessing different dimensions of delirium symptomatology. Exploratory factor analysis was conducted in order to examine which symptoms clustered.
Results: Factor analysis confirmed the existence of two different clusters of symptoms: first, symptoms of hyperalert/hyperactive features (agitation, hyper-reactivity, aggressiveness, hallucinations, delusions); and second, symptoms of hypoalert/hypoactive features (decreased reactivity, motor and speech retardation, facial inexpressiveness).
Conclusion: This preliminary study seems to support the evidence of hypoactive and hyperactive subtypes of delirium, even though their aetiology and prognostic values need to be further examined.
Copyright 2000 John Wiley & Sons, Ltd.