Pseudodementia twelve years on.

This paper reports a longitudinal study of 19 patients diagnosed as having pseudodementia more than a decade earlier. In only one patient was the earlier diagnosis changed to definite dementia and, in this patient, there were strong indicators that such a diagnosis should have been made initially. In a second patient, dementia could not be excluded. The remaining patients did not show evidence of a dementing illness and the courses of the illnesses resembled the primary psychiatric disorders responsible for the pseudodementia. The results validate the clinical utility of the term "pseudodementia".