Very late-onset schizophrenia-like psychosis: clinical and imaging characteristics in comparison with elderly patients with schizophrenia.

Studies of late-onset schizophrenia began in the early 1940s with work by M. Bleuler. Despite this fact, the emphasis on age of onset in young adulthood distracted researchers of schizophrenia from accumulating data on the subgroup of patients whose disease onset is in late life. Recently, the diagnostic entity of very late-onset schizophrenia-like psychosis (VLOSLP) was proposed for patients with disease onset after age 60 years, and it may have validity and clinical utility. The present study aims to prospectively identify patients suffering from VLOSLP over a 2-year period and to compare them with elderly schizophrenia patients on measures of brain structure, demographics, and treatment response, so that distinct features, if any, can be identified. Twenty-one VLOSLP patients (15 women, 6 men; mean age, 78.1 years) were enrolled and compared with 21 age- and gender-matched elderly schizophrenia patients. All had undergone brain CT scan, and all were treated with risperidone. The VLOSLP group was characterized by more education, higher percentage being married, more pronounced cerebellar atrophy, and better response to treatment. The authors suggest that VLOSLP is a valid diagnostic entity and that its features imply that involvement of neurodegenerative process may be etiologically relevant to psychosis with onset in late life.