Late-onset schizophrenia: an overview.

Onset of schizophrenia after the age of 40 has been a controversial topic. We reviewed more than 30 publications (mainly from Europe) on this subject. Many of the studies had methodological shortcomings, including problems in precisely dating the onset of schizophrenia. Nonetheless, it appears that a certain proportion of patients present for the first time with diagnosable schizophrenia after age 40. Late-onset schizophrenia is characterized by paranoid symptomatology, a high female:male ratio, an elevated prevalence of hearing loss and ocular pathology, schizoid or paranoid traits in premorbid personality, a tendency toward chronicity, and symptomatic improvement with neuroleptics. Family studies suggest that the prevalence of schizophrenia in relatives of late-onset schizophrenic probands is higher than that in the general population, but lower than that in relatives of earlier-onset schizophrenic probands. We believe that late-onset schizophrenia is a valid entity (or group of entities). Studies of the course, biological associations, neuropsychological performance, and pharmacological characterization of late-onset schizophrenia are warranted.