Swedish Universities Scales of Personality: Relation to Other Personality Instruments

Correlations between personality traits, personality disorders, and immunometabolic markers

Evidence links immune system alterations to major psychiatric disorders. The few previous studies on personality traits or personality disorders (PDs) indicate that immunometabolic dysregulation may be prevalent in this population. This study aimed to investigate relationships between personality traits, PDs, and immunometabolic markers in peripheral blood. We hypothesized that neuroticism would be correlated with elevated leptin. Participants were recruited as young adults seeking care for general psychiatric disorders. They responded to a personality inventory and were assessed for PDs, and reevaluated again at a 12 years follow-up. Blood samples were collected at the follow-up and analyzed for 29 immunometabolic markers. A positive correlation was found between the personality trait neuroticism and leptin (ρ = 0.31, p = 0.02). An exploratory analysis also revealed a positive correlation between brain-derived neurotrophic factor (ρ = 0.36, p < 0.01) and neuroticism. These findings remained after adjusting for other variables in general linear models. There were no relationships between PDs and any immunometabolic markers. Results both confirm previous findings of correlations between the immunometabolic system and personality traits and suggest directions for future research.

Thirteen-year follow-up of long-term treated psychotic disorder: personality aspects

OBJECTIVE

Personality is an aspect that can affect the symptoms and social function in individuals with psychotic disorders. Several studies have investigated personality in schizophrenia and other long-term psychotic disorders. No study has examined the stability of personality traits exceeding five years in patients with schizophrenia and related disorders. The aim of this study was to investigate the stability of personality traits over a 13-year period among patients with schizophrenia and related disorders and healthy individuals and to evaluate case-control differences.

METHODS

At three occasions during a 13-year period patients with schizophrenia and related disorders (n = 28) and healthy individuals (n = 57) completed Swedish universities Scales of Personality (SSP). Mean-level change and case-control differences were investigated for all the individuals using within- and between-subject analyses, respectively. Analyses were performed on three occasions for all 13 subscales and the three overall factors of SSP. Also, correlations, means, and SDs were calculated.

RESULTS

Tests of within-subject correlations showed differences in two subscales: Lack of Assertiveness, which were influenced by age, and Physical Trait Aggression, where patients' ratings were stable, whereas controls rated themselves less aggressive at a higher age. Between-subjects correlations showed differences regarding diagnosis, time, age, gender, or age × gender in nine of the 13 subscales as well as in factor Neuroticism.

CONCLUSION

Long-term follow-up showed generally high stability of personality traits measured with SSP. Between-subject analyses over the 13 years showed that patients differed compared to controls for the SSP factor Neuroticism as well as the subscale Detachment, which is in accordance with previous studies within this population.

Cluster analysis of personality traits in psychiatric patients with borderline personality disorder

BACKGROUND

Though the heterogeneous expression of symptoms of borderline personality disorder (BPD) is well-known, it is far from fully understood. Hybrid models combining dimensional and categorical ways of diagnosing BPD have been suggested to better handle this heterogeneity, but more research is needed. The aim of this study was to identify potential clusters in BPD, and evaluate if these clusters differed in diagnostic composition, severity, psychiatric symptoms, emotion regulation and control, or sociodemographic features.

METHODS

Clusters were based on personality traits measured with the Swedish universities Scales of Personality (SSP) in 141 psychiatric patients diagnosed with BPD. Hierarchical cluster analysis was performed using Ward's method. We used one-way analysis of variance to explore the different clusters' properties. Effect sizes were calculated using partial eta squared.

RESULTS

We found three distinct clusters: the lower psychopathology cluster (N = 67), the externalizing cluster (N = 28), and the internalizing cluster (N = 46). The clusters differed regarding trait composition, severity, and emotion regulation and control.

CONCLUSIONS

Our findings support hybrid models for diagnosing BPD by showing that clusters differed in terms of both severity (lower and higher psychopathology) and personality traits/style (internalizing and externalizing). Assessment of personality traits may be a feasible way to differentiate between clusters. In the future, this knowledge might be used to personalize treatment.