BACKGROUND: Although the fourth edition of the Diagnostic and Statistical Manual of Mental Disorders abandoned the use of the specifier 'late-onset', a considerable number of studies have reported clinical characteristics of late-onset schizophrenia. Still, only limited research has been conducted on late-onset schizophrenia, especially in Asian countries. In this epidemiological study, the clinical characteristics of late-onset schizophrenia were examined in comparison with early-onset schizophrenia. METHODS: All patients with schizophrenia admitted to the psychiatric ward of Jichi Medical University Hospital between 1 April 1993 and 31 March 2006 were divided into two groups according to age at first onset: ≥40 years (late-onset group) and <40 years (early-onset group). The sex ratio, presence or absence of depression, schizophrenia subtype, premorbid character, marital history, and employment history at first onset were compared between the two groups. RESULTS: Of the 316 patients with schizophrenia identified, 38 patients were assigned to the late-onset group and 278 patients to the early-onset group. Mean age at onset was 23.9 ± 8.2 years for all men and 28.0 ± 13.5 years for all women. The late-onset group was characterized by more women, more paranoid type, more depressive symptoms, less introverted premorbid character, better premorbid adaptation and less neuroleptics. CONCLUSION: The characteristics of late-onset schizophrenia in Japan are in line those reported previously.
BACKGROUND: Although the fourth edition of the Diagnostic and Statistical Manual of Mental Disorders abandoned the use of the specifier 'late-onset', a considerable number of studies have reported clinical characteristics of late-onset schizophrenia. Still, only limited research has been conducted on late-onset schizophrenia, especially in Asian countries. In this epidemiological study, the clinical characteristics of late-onset schizophrenia were examined in comparison with early-onset schizophrenia. METHODS: All patients with schizophrenia admitted to the psychiatric ward of Jichi Medical University Hospital between 1 April 1993 and 31 March 2006 were divided into two groups according to age at first onset: ≥40 years (late-onset group) and <40 years (early-onset group). The sex ratio, presence or absence of depression, schizophrenia subtype, premorbid character, marital history, and employment history at first onset were compared between the two groups. RESULTS: Of the 316 patients with schizophrenia identified, 38 patients were assigned to the late-onset group and 278 patients to the early-onset group. Mean age at onset was 23.9 ± 8.2 years for all men and 28.0 ± 13.5 years for all women. The late-onset group was characterized by more women, more paranoid type, more depressive symptoms, less introverted premorbid character, better premorbid adaptation and less neuroleptics. CONCLUSION: The characteristics of late-onset schizophrenia in Japan are in line those reported previously.