Premorbid Adjustment in Bipolar Disorder
Von: Dipl.-Psych. Alexander Georgi | 24.03.2014
Premorbid Adjustment in Bipolar Disorder:
Why being superior is not always good*
* Untersuchung von Alexander Georgi (Sigma Tagesklinik, Bad Säckingen) sowie Christine Schmael, Frederike Schirmbeck, Jana Strohmaier, Katja Bößhenz, Marcella Rietschel (Department of Genetic Epidemiology in Psychiatry, Central Institute of Mental Health, Mannheim),Markus M. Nöthen (Life and Brain Center, University of Bonn), Thomas G. Schulze (Clinical Research Group 241, University of Göttingen), präsentiert auf dem 15ten World Congress of Psychiatric Genetics der International Society of Psychiatric Genetics (ISPG).
Disentangling the various environmental and biological factors involved in the etiology and course of psychiatric disorders is a prerequisite for the development of effective treatment and potentially prevention strategies. As for genetic research, the ever increasing sophistication of molecular genetic tools is accompanied by a call for a thorough assessment and systematic exploitation of all available phenotype information.
For the case of schizophrenia (SCZ) or bipolar disorder (BIP), several phenotypic variables have been suggested as targets for phenotypic dissection. Premorbid adjustment (PMA) has joined the list of phenotypes that may delineate specific biological subtypes (Schmael et al. 2007). There is consistent evidence that PMA is worse in individuals developing SCZ than in controls. For BIP, research into PMA is scarce and inconclusive.
Objective and Methods
We compared the level of PMA in individuals who later in life develop BIP with healthy controls and investigated whether levels of PMA in BIP patients are associated with specific phenotypic features (see Table 1).Study Sample
- 344 BIP type I patients
182 (53%) female, 162 (47%) male
mean age 45.1±12.8 years
- 137 healthy controls
80 (58%) female, 57 (42%) male
mean age 45.9±14.5 years
PMA was assessed using the Premorbid Adjustment Scale (PAS) by Cannon-Spoor (1982). To increase the comparability of our study with previous studies, we re-analyzed our previously published data set on PMA in SCZ (Schmael et al. 2007) and compared PMA between BIP and SCZ patients.
Bipolar patients performed significantly better than healthy controls during early and late adolescence and had better PAS scores in the domains “sociability and withdrawal” , “adaptation to school” as well as a better overall score. For no life period of PAS domain did controls show better scores than patients. The re-analysis of our SCZ data revealed that BIP patients had significantly lower PAS scores than SCZ patients for all scales.
Out of the ten phenotypic characteristics of BIP studied, only “sex”, “suicidal ideation” and “alcohol or drug abuse or dependence” showed significant associations with the PAS. However, these associations did not reach the required p-value thresholds after Bonferroni-Holm correction (Table 1).
Since the most obvious overlap between BIP and SCZ are psychotic symptoms, we compared the PAS scores of BIP patients with versus BIP patients without psychotic symptoms. We find no differences between these Groups (Figure 2).
The retrospective assessment of PMA may be influenced by recall biases contingent on the polarity of mood episodes, leading to an overestimation of PMA by euphoric patients. In order to detect biases, we tested whether the polarity of the last episode impacted on PAS ratings (Figure 3) and additionally compared patients‘ rating with those of their parents (Figure 4).
There is no detectable difference between the groups “last episode manic” and “last episode depressive”.
Except on the scale “Socio-Sexual Aspects of Life”, parents rate their children better than the children do themselves.
Summary and Conclusions
- BIP patients are premorbidly better adapted than
SCZ patients and healthy controls.
- There is no difference in PMA between BIP patients with or without psychotic symptoms.
- Contrary to SCZ, PMA in BIP may not be a proxy for markers of severity.
- PMA as measured with the PAS may be a marker for an aspect of difference between SCZ and BIP.
References: Schmael, C., Georgi, A., Krumm, B., Buerger, C., Deschner, M., Nöthen, M. M., Schulze, T. G. & Rietschel, M. (2007). Premorbid adjustment in schizophrenia – An important aspect of phenotype definition. Schizophrenia Research
Acknowledgements: We are grateful to all individuals who participated in this study. This study was supported by the National Genome Research Network (NGFN) of the German Ministry of Education and Research (BMBF), the Deutsche Forschungsgemeinschaft (SFB 636), and NARSAD: The Mental Health Research Association (Great Neck, NY, USA).