Premorbid adjustment: a phenotype highlighting a distinction rather than an overlap between schizophrenia and bipolar disorder.
BACKGROUND
Premorbid adjustment (PMA) in schizophrenia (SZ) has been widely studied and shown to be worse in individuals who develop SZ as compared to controls. It has been proposed as a predictor of clinical presentation and outcome, and may delineate a specific SZ phenotype for genetic and other biological studies. Research into PMA in BD has been scarce and inconclusive.


OBJECTIVE
The authors compared PMA in individuals suffering from BD with that of healthy controls and investigated whether levels of PMA in BD patients correlate with specific phenotypic features.


METHODS
The authors investigated 344 BD patients and 137 population-based controls. Retrospective PMA assessment was performed using the Premorbid Adjustment Scale (PAS). An overall score as well as sub-scores for age ranges and functional domains were obtained.


RESULTS
Patients had a better overall PAS score than controls and outperformed controls during early and late adolescence. They scored significantly better than controls in the functional domains "sociability and withdrawal" and "adaptation to school". No differences were observed for the other subscales and there were no differences between groups during childhood. No association was observed between PMA and any of the phenotype characteristics investigated.


CONCLUSIONS
In the largest study to date on PMA in BD, PMA was shown to be better in bipolar patients than in healthy controls. PMA in BD is not a simple proxy for commonly studied phenotypic markers of severity. PMA emerges as a phenotype in its own right, and highlights an aspect of disparity rather than overlap between SZ and BD.
Department of Genetic Epidemiology in Psychiatry, Central Institute of Mental Health, Mannheim, Germany.
Marcella
M
Rietschel
Alexander
A
Georgi
Christine
C
Schmael
Frederike
F
Schirmbeck
Jana
J
Strohmaier
Katja V
KV
Boesshenz
Markus
M
Schwarz
Markus M
MM
Nöthen
Thomas G
TG
Schulze
D000275:Adjustment Disorders / Q000175:diagnosis / Q000453:epidemiology*; D000293:Adolescent; D000328:Adult; D000368:Aged; D015982:Bias; D001714:Bipolar Disorder / Q000175:diagnosis* / Q000453:epidemiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D011569:Psychiatric Status Rating Scales; D000067759:Receptor for Advanced Glycation End Products; D011971:Receptors, Immunologic; D012559:Schizophrenia / Q000175:diagnosis* / Q000453:epidemiology*; D012565:Schizophrenic Psychology; D012737:Sex Factors; D018709:Statistics, Nonparametric; D055815:Young Adult
D000067759:Receptor for Advanced Glycation End Products; D011971:Receptors, Immunologic