To some extent, all diagnoses in psychiatry are surrounded by uncertainty, but late paraphrenia is certainly among the most controversial. A number of factors have contributed to late paraphrenia's appararently uncertain position as a diagnostic category. Delusions and hallucinations, the basic clinical features of late paraphrenia, have their onset most frequently in early or middle life, and are then usually associated with the diagnoses of schizophrenia or delusional disorder. Conversely, psychotic symptoms appearing for the first time in late life are frequently associated with organic mental disorders (Burns, Jacoby & Levy, 1990). To complicate this further, the use of the Kraepelinian term ‘paraphrenia’ is itself surrounded by uncertainties, particularly since Mayer (1921) demonstrated that most paraphrenics became indistinguishable from schizophrenics at follow-up. It is hardly surprising that the diagnostic category of late paraphrenia has been all but abandoned from the current psychiatric nosology (Quintal, Day-Cody & Levy, 1991). Recent evidence, however, suggests that its death sentence may have been premature.

How late paraphrenia came into existence

The term ‘paraphrenia’ was introduced by Emil Kraepelin (1919) to describe a group of paranoid patients with marked delusions and hallucinations in whom affect, will and personality were largely preserved. Kraepelin (1919) admitted that it was often difficult to separate paraphrenia from dementia praecox and estimated that approximately 40% of his patients would progress to exhibit the features of dementia praecox with time.

Mayer (1921) carried out a follow-up of Kraepelin's original paraphrenic patients and found that only a tiny minority of them had failed to develop the features of dementia praecox.