Late‐onset paranoia: Distinct from paraphrenia?

Using Kraepelin's distinction between paraphrenia and paranoia, 21 patients with late paraphrenia were compared with 12 with late‐onset paranoia. The paranoia group had significantly more clinically unsuspected (silent) cerebral infarction on CT brain scan and was less responsive to antipsychotic medication. The results suggest that cerebral organicity, especially stroke, is an important risk factor for late‐onset paranoia and may contribute to a relatively poor prognosis.