[Late-onset schizophrenia or chronic delusion].

Area of Science:

• Psychiatry
• Neurology

Context:

• Historical definitions of late-onset schizophrenia vary across European and American psychiatric traditions.
• The concept of "late-onset paraphrenia" in British psychiatry encompasses delusional disorders starting after age 60.
• French nosography categorizes late-onset non-affective psychosis as "Psychose Hallucinatoire Chronique".

Purpose:

• To define the characteristics of late-onset schizophrenia based on existing literature.
• To explore the prevalence, demographics, and clinical features of this patient group.
• To discuss potential etiological factors and treatment considerations.

Summary:

• Late-onset schizophrenia, affecting less than 1% of the population, predominantly impacts women and is associated with premorbid paranoid/schizoid traits and sensory impairments.
• Patients often present with delusions and hallucinations limited to their environment, with fewer negative symptoms and looser associations compared to early-onset cases.
• Family studies indicate a lower risk in first-degree relatives, suggesting distinct genetic or environmental influences.

Impact:

• Understanding late-onset schizophrenia aids in developing targeted diagnostic and therapeutic strategies.
• Identifying trigger factors could lead to predictive models for early intervention.
• Clarifies the distinction and overlap between late-onset schizophrenia and other late-life delusional disorders.