Karolinska Scales of Personality, cognition and psychotic symptoms in patients with schizophrenia and healthy controls

The differential associations of positive and negative symptoms with suicidality

BACKGROUND

Suicide is one of the leading causes of death in people with schizophrenia. Identifying risk factors for suicide in schizophrenia is therefore an important clinical and research priority.

METHOD

A cross-sectional secondary analysis was conducted on the DNA Polymorphisms in Mental Illness Study (DPIM) data. Suicidality data was extracted, and the number of positive and negative symptoms were established for a total of 1494 participants. Logistic and negative binomial regression analyses were conducted to assess for associations between positive or negative symptoms and suicidal ideation, attempt, or number of attempts, whilst adjusting for potential confounders.

RESULTS

Negative symptoms were associated with a reduction in the risk of suicidal ideation (odds ratio [OR]: 0.83; 95 % CI: 0.75-0.91) and suicide attempt (OR: 0.79; 95 % CI: 0.71-0.88) after adjusting for age and sex. Positive symptoms were associated with an increased risk of suicidal ideation (OR: 1.06; 95 % CI: 1.03-1.09), suicide attempt (OR: 1.04; 95 % CI: 1.00-1.07) and number of suicide attempts (incidence rate ratio [IRR]: 1.05; 95 % CI: 1.01-1.08). Further adjusting for depressive symptoms slightly increased the magnitude of associations with negative symptoms but attenuated associations between positive symptoms and suicidality to the null.

CONCLUSIONS

Negative symptoms are associated with a reduced risk of suicidality, whilst positive symptoms are associated with an increased risk of suicidality. Depressive symptoms may confound or mediate these associations.

The diagnostic and predictive potential of personality traits and coping styles in major depressive disorder

BACKGROUND

Major depressive disorder (MDD) is a global public health concern that is notably underdiagnosed and undertreated due to its complexity and subjective diagnostic methods. A holistic diagnostic procedure, which sufficiently considers all possible contributors to MDD symptoms, would improve MDD diagnosis and treatment. This study aims to explore whether personality and coping styles can predict MDD status and differentiate between depressed patients and healthy individuals.

METHODS

Seventy healthy controls (N = 54 females) were matched to 70 MDD patients for age, sex, ethnicity, and years of education. MDD severity was measured using the Hamilton Depression Rating Scale, while personality traits and coping styles were measured by the Ten-Item Personality (TIPI) and Brief COPE questionnaires, respectively. Logistic regression analyses were conducted to investigate the diagnostic and predictive potential of personality and coping styles. Receiver operating characteristic (ROC) analyses were also conducted to examine their discriminative ability to distinguish between depressed and healthy individuals.

RESULTS

Introversion, lack of organisation skills, and neuroticism were statistically significant in predicting MDD status. Dysfunctional coping strategies, such as denial and self-blame, were also shown to significantly predict MDD status. ROC analyses found both the TIPI questionnaire (AUC = 0.90), and dysfunctional coping (as measured by Brief COPE) (AUC = 0.90) to be excellent predictors of MDD.

CONCLUSIONS

Our findings demonstrate the diagnostic and predictive potential of personality and coping styles for MDD in the clinical setting. They also demonstrate the remarkable ability of personality and coping styles to differentiate between depressed patients and healthy controls.

Marginal relationship between affective dispositions and neurocognitive function in patients with schizophrenia spectrum disorders

PURPOSE

Neurocognitive outcomes are frequently used as indicators of real-world functioning in schizophrenia spectrum disorders (SSD). These test results may be influenced by individual differences, such as affective dispositions. Here we investigate the relationship between positive and negative affect and neuropsychological test scores in a large, mixed-gender, population based group of participants without co-morbid substance abuse.

MATERIALS AND METHODS

We assessed 129 male and female SSD patients with the Positive and Negative Affect Schedule (PANAS) and a comprehensive neuropsychological test battery.

RESULTS AND CONCLUSIONS

The neuropsychological test scores were mainly predicted by age and gender, with small contributions from negative psychosis symptoms. There was a statistically significant relationship between Positive Affect and processing speed and between Negative Affect and verbal memory and executive function. However, the level of neurocognitive function variance explained by these affects was only 5%. Thus, the neurocognitive test results were not associated with trait affect in any clinically significant manner. This adds to previous findings of no relationship between affective dispositions and psychosis symptom variables in our participants. We suggest that affective traits constitute an independent dimension that may influence well-being, coping, and real-life outcome in SSD patients directly, and not through neurocognitive function.

Long-term stability of personality traits in a clinical psychiatric sample

Background: The aim of this study was to describe personality traits in psychiatric patients and to investigate whether these traits are stable over 13 years. Methods: A total of 95 individuals who were patients at a psychiatric outpatients' clinic in 2003 completed the Swedish universities Scales of Personality (SSP). Scores from 2003 were compared with SSP scores from 2016. Based on the current score on the comprehensive psychopathological rating scale - self rating for affective disorders (CPRS-S-A), the participants were divided into two groups representing 'good' and 'poor' current mental states, to investigate the effect of current mental state on reports of personality traits. Results: Out of 13 personality traits, 11 showed a significant change in mean T-score over the study interval. The group with lower CPRS-S-A scores showed a significant change in T-score for 10 traits, whereas in the group with higher CPRS-S-A scores only 3 traits showed a significant change. Conclusions: The findings support the theory that personality is changeable over the course of life, also in psychiatric patients. We do not know if persisting psychiatric symptoms halter change or if deviant personality traits cause psychiatric symptoms to continue.

Stability of personality traits over a five-year period in Swedish patients with schizophrenia spectrum disorder and non-psychotic individuals: a study using the Swedish universities scales of personality

BACKGROUND

Personality is considered as an important aspect in persons with psychotic disorders. Several studies have investigated personality in schizophrenia. However, no study has investigated stability of personality traits exceeding three years in patients with schizophrenia. This study aims to investigate the stability of personality traits over a five-year period among patients with schizophrenia and non-psychotic individuals and to evaluate case-control differences.

METHODS

Patients with psychotic disorders (n = 36) and non-psychotic individuals (n = 76) completed Swedish universities Scales of Personality (SSP) at two occasions five years apart. SSP scores were analysed for effect of time and case-control differences by multiple analysis of covariance (MANCOVA) and within-subjects correlation.

RESULTS

MANCOVA within-subjects analysis did not show any effect of time. Thus, SSP mean scale scores did not significantly vary during the five-year interval. Within subject correlations (Spearman) ranged 0.30-0.68 and 0.54-0.75 for the different SSP scales in patients and controls, respectively. Patients scored higher than controls in SSP scales Somatic Trait Anxiety, Psychic Trait Anxiety, Stress Susceptibility, Lack of Assertiveness, Detachment, Embitterment, and Mistrust.

CONCLUSION

The stability of the SSP personality trait was reasonably high among patients with psychotic disorder, although lower than among non-psychotic individuals, which is in accordance with previous research.

Trait impulsiveness is related to smaller post-commissural putamen volumes in males but not females

Impulsivity is considered a vulnerability trait for addiction. Recently, we found trait non-planning impulsiveness measured with the Karolinska Scales of Personality was negatively correlated with dopamine D_2/3 receptor availability in the ventral striatum of healthy humans. While also observed in rodents, human studies have failed to find this association with other measures of trait impulsivity. We explored whether another rodent finding, reduced ventral striatum volume with greater impulsivity, could also be observed in humans using this scale. Non-planning impulsiveness was measured in 52 healthy subjects (21 female; mean age: 33.06 ± 9.69) using the Karolinska Scales of Personality. Striatal subregion volumes, including the globus pallidus, were acquired using the Multiple Automatically Generated Templates (MAGeT-Brain) algorithm. Although failing to support our a priori hypothesis, there was a significant sex interaction in the post-commissural putamen with impulsiveness. Exploratory analyses revealed impulsiveness was negatively correlated with post-commissural putamen volumes in males, but positively correlated in females. We replicated this finding in males in an increased sample (including all 52 previous subjects) who provided impulsiveness measured by the Temperament and Character Inventory (n = 73; 32 female; mean age: 33.48 ± 9.75). These correlations by sex were statistically different from one another, the main finding with the Kasolinksa Scales of Personality surviving correction for multiple comparisons. While impulsivity may be related to reduced ventral striatal D_2/3 receptors across sexes, males but not females may show significant reductions in post-commissural putamen volume. These findings have important implications for understanding biological markers underlying sex differences in drug addiction vulnerability.

Personality traits in established schizophrenia: aspects of usability and differences between patients and controls using the Swedish universities Scales of Personality

BACKGROUND

Personality is considered as an important aspect that can affect symptoms and social function in persons with schizophrenia. The personality questionnaire Swedish universities Scales of Personality (SSP) has not previously been used in psychotic disorder.

AIMS

To investigate if SSP has a similar internal consistency and factor structure in a psychosis population as among healthy controls and if patients with psychotic disorders differ from non-psychotic individuals in their responses to the SSP.

METHODS

Patients with psychotic disorders (n = 107) and healthy controls (n = 119) completed SSP. SSP scores were analyzed for internal consistency and case-control differences by Cronbach's alfa and multiple analysis of covariance, respectively.

RESULTS

Internal consistencies among patients were overall similar to that of controls. The patients scored significantly higher in seven (Somatic trait anxiety, Psychic trait anxiety, Stress susceptibility, Lack of assertiveness, Detachment, Embitterment, Mistrust) and lower in three (Physical trait aggression, Verbal trait aggression, Adventure seeking) of the 13 scales of the inventory. In three scales (Impulsiveness, Social desirability and Trait irritability) there was no significant difference between the scoring of patients and healthy controls.

CONCLUSION

The reliability estimates suggest that SSP can be used by patients with psychotic disorders in stable remission. Patients score higher on neuroticism-related scales and lower on aggression-related scales than controls, which is in accordance with earlier studies where other personality inventories were used.