First-onset functional brief psychoses in the elderly.

Background And Purpose: The origin and nosological status of psychotic states first arising in late life remain uncertain. We aimed to evaluate the diagnostic stability of brief psychoses with late-life onset.

Methods: A 10-year retrospective analysis of all records of elderly patients with a first-ever episode of psychosis was undertaken.

Results: Of 2,072 admissions of elderly patients, 604 had their first brief psychotic disorder (International Classification of Diseases diagnoses). All "organic" psychoses were excluded. The study sample comprised 83 individuals (36 male, 47 female) with a mean ± SD age of 75.4±9.3 years (range: 65-92). Mean follow-up duration was 27.7 months (range: 6-120). Distribution of diagnoses was as follows: unspecified nonorganic psychosis (n = 71); persistent delusional disorder (n = 10); other nonorganic psychosis (n = 1); and acute and transient psychotic disorder (n = 1). At follow-up, diagnosis of very late-onset schizophrenia-like psychosis and switch to another brief psychotic disorder were the most frequent outcomes.

Conclusions: The diagnosis of a nonorganic psychosis first manifesting in the elderly is not rare in tertiary care. Diagnostic shift at follow-up of these patients is more common than conceptualized, requiring flexibility on the part of treating physicians.