Diagnostic change 10 years after a first episode of psychosis.
BACKGROUND
A lack of an aetiologically based nosology classification has contributed to instability in psychiatric diagnoses over time. This study aimed to examine the diagnostic stability of psychosis diagnoses using data from an incidence sample of psychosis cases, followed up after 10 years and to examine those baseline variables which were associated with diagnostic change.


METHODS
Data were examined from the ÆSOP and ÆSOP-10 studies, an incidence and follow-up study, respectively, of a population-based cohort of first-episode psychosis cases from two sites. Diagnosis was assigned using ICD-10 and DSM-IV-TR. Diagnostic change was examined using prospective and retrospective consistency. Baseline variables associated with change were examined using logistic regression and likelihood ratio tests.


RESULTS
Slightly more (59.6%) cases had the same baseline and lifetime ICD-10 diagnosis compared with DSM-IV-TR (55.3%), but prospective and retrospective consistency was similar. Schizophrenia, psychotic bipolar disorder and drug-induced psychosis were more prospectively consistent than other diagnoses. A substantial number of cases with other diagnoses at baseline (ICD-10, n = 61; DSM-IV-TR, n = 76) were classified as having schizophrenia at 10 years. Many variables were associated with change to schizophrenia but few with overall change in diagnosis.


CONCLUSIONS
Diagnoses other than schizophrenia should to be regarded as potentially provisional.
Centre for Economics of Mental and Physical Health,King's College London,London,UK.
M
M
Heslin
Division of Psychiatry,University of Nottingham,Nottingham,UK.
B
B
Lomas
Department of Psychiatry,University of New South Wales,Sydney,Australia.
J M
JM
Lappin
Addictions Department,King's College London,London,UK.
K
K
Donoghue
Centre for Epidemiology and Public Health,King's College London,London,UK.
U
U
Reininghaus
Department of Psychology,King's College London,London,UK.
A
A
Onyejiaka
School of Nursing and Midwifery,College of Medicine, Dentistry and Nursing,University of Dundee,Dundee,UK.
T
T
Croudace
Department of Psychiatry,University of Cambridge,Cambridge,UK.
P B
PB
Jones
Psychosis Studies Department,King's College London,London,UK.
R M
RM
Murray
Department of Psychiatry,Trinity College,Dublin,Republic of Ireland.
P
P
Fearon
Psychosis Studies Department,King's College London,London,UK.
P
P
Dazzan
Centre for Epidemiology and Public Health,King's College London,London,UK.
C
C
Morgan
Division of Psychiatry,University of Nottingham,Nottingham,UK.
G A
GA
Doody
D000328:Adult; D001714:Bipolar Disorder / Q000175:diagnosis*; D015331:Cohort Studies; D003937:Diagnosis, Differential; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005260:Female; D006801:Humans; D038801:International Classification of Diseases / Q000592:standards*; D016015:Logistic Models; D008297:Male; D011618:Psychotic Disorders / Q000175:diagnosis*; D012559:Schizophrenia / Q000175:diagnosis*; D055815:Young Adult
Diagnosis; first-episode psychosis; psychoses