title: How common are psychotic and bipolar disorders? A 50-year follow-up of the Lundby population.
abstract: BACKGROUND
  The purpose was to present the prevalence of all psychotic and bipolar (BP) disorders in a total general population (n=3563), which has been followed from 1947 to 1997.
  
  
  METHODS
  Best-estimate consensus DSM-IV diagnoses, supported by data from interviews, case notes, registers and key-informants, were assessed. The period prevalence from 1947 to 1997 and the lifetime prevalence (LTP) in 1997, respectively, was calculated.
  
  
  RESULTS
  The period prevalence per 100 was: 4.24 for any psychotic or BP disorder, 2.25 for non-affective psychotic (NAP) disorder, 0.76 for psychotic disorder related to a general medical condition (GMC), 0.62 for affective psychotic (AP) disorder and 0.59 for substance-induced psychotic (SIP) disorder. The LTP per 100 was: 2.82 for any psychotic or BP disorder, 1.38 for NAP disorder, 0.54 for psychotic disorder related to a GMC, 0.48 for SIP disorder and 0.42 for AP disorder. The specific diagnosis with the highest period prevalence 1.43 per 100 and LTP 0.84 per 100, respectively, was schizophrenia. The LTP of psychotic disorder related to a GMC, SIP disorder, schizophrenia and delusional disorder, respectively, was higher than in most recent community studies while the LTP of brief psychotic disorder, schizophreniform disorder and AP disorder, respectively, was lower. However, the findings were in approximate accord with the estimates in the Psychoses in Finland (PIF) Study 1.
  
  
  CONCLUSIONS
  The findings suggest that psychotic disorders are common in the community, and should be considered a major public health concern.
authors.affiliation: Department of Clinical Sciences, Division of Psychiatry, the Lundby Study, Lund University Hospital, St Lars, Lund SE-221 85, Sweden. mats.bogren@med.lu.se
authors.forename: Mats
authors.initials: M
authors.lastname: Bogren
authors.forename: Cecilia
authors.initials: C
authors.lastname: Mattisson
authors.forename: Per-Erik
authors.initials: PE
authors.lastname: Isberg
authors.forename: Per
authors.initials: P
authors.lastname: Nettelbladt
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001714:Bipolar Disorder / Q000175:diagnosis / Q000453:epidemiology*; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005260:Female; D006801:Humans; D015994:Incidence; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D011159:Population Surveillance; D011618:Psychotic Disorders / Q000175:diagnosis / Q000453:epidemiology*; D012559:Schizophrenia / Q000175:diagnosis / Q000453:epidemiology; D012563:Schizophrenia, Paranoid / Q000175:diagnosis / Q000453:epidemiology; D013548:Sweden