[Delirium in the elderly and DSM IV: is there clarity about confusion?]

On the occasion of the recent presentation of DSM IV, this article offers survey of current insights concerning delirium, an important psychogeriatric disorder. Compared with DSM III and IIIR, diagnostic criteria in DSM IV have been enlarged and simplified. This has been done in order to improve clinical diagnosis, especially of mild manifestations of delirium. Also, some of the former criteria were rather ambiguous and could easily be attributed to preexisting medical conditions. DSM IV diagnostic criteria for delirium allow consideration of this diagnosis, even in the absence of indications for a presumed organic etiological factor. This will facilitate future research into the etiological contribution of non-organic factors. Scientific research over the past decades strongly suggests that delirium in the elderly is far from a benign transient disorder. Besides adequate diagnosis and treatment, preventive measures are therefore of equal relevance.