title: Age-at-first-registration for affective psychosis and schizophrenia.
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.
authors.affiliation: Queensland Centre for Mental Health Research, University of Queensland, Wolston Park Hospital, Wacol, Australia. joy_welham@qcmhr.uq.edu.au
authors.forename: Joy L
authors.initials: JL
authors.lastname: Welham
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Thomis
authors.forename: John J
authors.initials: JJ
authors.lastname: McGrath
mesh_terms: D000328:Adult; D000339:Affect; D000367:Age Factors; D017668:Age of Onset; D000368:Aged; D005260:Female; D006801:Humans; D038801:International Classification of Diseases; D008297:Male; D008875:Middle Aged; D011618:Psychotic Disorders / Q000175:diagnosis / Q000209:etiology*; D012559:Schizophrenia / Q000150:complications* / Q000175:diagnosis* / Q000453:epidemiology