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Handwriting Analysis Indicates Spontaneous Dyskinesias in Neuroleptic Naïve Adolescents at High Risk for Psychosis
Published on: November 21, 2013
Age-at-first-registration for affective psychosis and schizophrenia
Joy L Welham1, Richard J Thomis, John J McGrath
1Queensland Centre for Mental Health Research, University of Queensland, Wolston Park Hospital, Wacol, Australia. joy_welham@qcmhr.uq.edu.au
Abstract:
We compared the age-at-first-registration for patients with schizophrenia and affective psychosis in a statewide mental health register. After excluding those receiving (1) a diagnosis of both schizophrenia (ICD-9 295.x) and affective psychosis (ICD-9 296.x), or (2) a diagnosis of ICD-9 296.1 (which can cover "major depressive episode"), we adjusted the distributions for the age structure of the background general population. We found that all distributions showed a wide age range of onset, with a similar male modal age group of 20-24 for schizophrenia and 25-29 for affective psychosis. The female modal age group was 50-54 for both diagnoses. Although more individuals were diagnosed with schizophrenia (males = 2,434, females = 1,609) than with affective psychosis (males = 670, females = 913), the shape of the two distributions was similar. This finding suggests that factors influencing age-at-first-registration for schizophrenia and affective psychosis may be similar, especially for females.
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