Association between aggressiveness, schizotypal personality traits and cannabis use in Swiss psychology students

A cross-sectional study of the relationship between frequency of cannabis use and psychiatric symptoms among people seeking mental health and addiction services in Nova Scotia (2019-21)

BACKGROUND

Cannabis use may be a modifiable risk factor for mental health problems; however, the role of cannabis use frequency in population seeking mental health and addiction services remains unclear. This study aimed to: 1) compare the prevalence and functional impact of psychiatric symptoms among frequent, infrequent, and non-users of cannabis; and 2) evaluate the associations between cannabis use frequency and functional impact of psychiatric symptoms in help-seeking individuals.

METHODS

Data from the Mental Health and Addictions (MHA) Central Intake system in Nova Scotia, Canada was used. Participants aged 19-64 who received MHA Intake assessments from September 2019 to December 2021 with complete information about substance use were included (N = 20,611). Cannabis use frequency over past 30 days was categorized into frequent (>4 times a month), infrequent (≤4 times a month), and non-use. Psychiatric symptomatology consists of five domains: mood, anxiety, psychosis, cognition, and externalizing behaviors. Multivariate ordinal logistic regression was used to examine the associations between cannabis use frequency and functional impact of psychiatric symptoms.

RESULTS

Frequent and infrequent cannabis users had a higher prevalence of psychiatric symptoms in each domain than non-users, while no significant differences were found between frequent and infrequent users. Frequent cannabis use was associated with greater functional impact of psychiatric symptoms in each domain compared to non-users, while infrequent use was only associated with greater functional impact of externalizing behaviors.

CONCLUSION

Frequent cannabis use is associated with increased prevalence and functional impact of psychiatric symptoms among adults seeking mental health services.

Characteristics of depression, anxiety, impulsivity, and aggression among various types of drug users and factors for developing severe depression: a cross-sectional study

BACKGROUND

Mood disorder, impulsivity and aggression are common in drug users compared to healthy controls. However, no study has focused on the difference in various types of drug users. Therefore, the objective of this study was to explore the differences in depression, anxiety, impulsivity, and aggression among methamphetamine, heroin and polysubstance users and to further explore the risk factors for severe depression in the three groups.

METHODS

Drug users over 18 years old who met the DSM-V diagnostic criteria for substance -related disorders were included in the study. All participants completed a general questionnaire, the Zung Self-Rating Depression Scale (SDS), the Zung Self-Rating Anxiety Scale (SAS), Barratt impulsiveness Scale Version 11 (BIS-11), and the Buss-Perry Aggression Questionnaire (BPAQ). One-way ANOVAs or Chi-square tests were used to test the differences among the groups, correlation analysis was used to test the relationship between drug use and other parameters, and multiple logistic regression was conducted to assess the risk factors for severe depression.

RESULTS

A total of 1,486 participants were included, comprising 86.3% males with a mean age of 38.97 years. There was a significant difference in the percentage of severe depression and SDS scores among the three groups, but no significant difference was found in SAS, BIS-11 and BPAQ scores. Using methamphetamines, hostility and anxiety were risk factors for developing severe depression in all the participants and anxiety remained constant in the other three groups. Moreover, methamphetamine use was 2.16 and 3.35 times more likely to cause severe depression than heroin and polysubstance use, respectively. The initial age of substance use was negatively correlated with BPAQ, SAS, and SDS scores, whereas the drug use duration and addiction duration were positively correlated.

CONCLUSIONS

In this study, we found that the highest prevalence of severe depression was in participants using methamphetamines and that using methamphetamines, hostility, and anxiety were risk factors for developing severe depression. This result addressed an important gap in our knowledge of the different characteristics of depression, anxiety, impulsivity and aggression in various types of substance users and provides clinicians and policy-makers with directions for intervention and preventing relapse.

Association of Schizoid and Schizotypal Personality disorder with violent crimes and homicides in Greek prisons

BACKGROUND

Personality disorders (PDs) have been associated with both violent crimes and homicides in many studies. The proportion of PDs among prisoners reaches up to 80%. For male prisoners, the most common PD in the literature is antisocial PD. The aim of this study was to investigate the association between PDs and violent crimes/homicides of male prisoners in Greece.

METHODS

A sample of 308 subjects was randomly selected from a population of 1300 male prisoners incarcerated in two Greek prisons, one urban and one rural. The presence of PDs was assessed using the Mini International Neuropsychiatric Interview (MINI) and the Personality Diagnostic Questionnaire-4 (PDQ-4). Using logistic regression models PD types and PD "Clusters" (independent variables) were associated with "violent/non-violent crimes" and "homicides/non homicides" (dependent variables).

RESULTS

"Cluster A" PDs (Paranoid, Schizoid, and Schizotypal) were diagnosed in 16.2%, "Cluster B" (Antisocial, Borderline, Histrionic, Narcissistic) in 66.9% and "Cluster C" (Obsessive-Compulsive, Dependent, Avoidant) in 2.9% of the studied population. Violent crimes and homicides were found significantly associated with "Cluster A" PDs (p = 0.022, p = 0.020). The odds ratio of committing violent crimes was 2.86 times higher for patients with "Cluster A" PDs than the ones without PDs. In addition, the odds ratio of committing homicides was 4.25 times higher for patients with "Cluster A" PDs. In separate analyses, the commitment of violent crimes as well as homicides, was significantly associated with Schizoid (p = 0.043, p = 0.020) and Schizotypal PD (p = 0.017, p = 0.030).

CONCLUSIONS

The majority of prisoners was found to suffer from a PD, mainly the Antisocial "Cluster B", but the commitment of violent crimes and homicides was significantly associated only with "Cluster A" PDs and specifically with Schizoid and Schizotypal PD.

Neural mediator of the schizotypy-antisocial behavior relationship

Prior studies have established that schizotypal personality traits (schizotypy) were associated with antisocial behavior (crime), but it is unclear what neural factors mediate this relationship. This study assessed the mediating effect that sub-regional prefrontal gray, specifically the orbitofrontal gray matter volume, has on the schizotypy-antisocial behavior relationship. Five prefrontal sub-regional (superior, middle, inferior, orbitofrontal and rectal gyral) gray matter volumes were assessed using structural magnetic resonance imaging in 90 adults from the community, together with schizotypy and antisocial behavior. Among all five prefrontal sub-regions, the orbitofrontal cortex (OFC) was the major region-of-interest in the present study. Mediation analyses showed that orbitofrontal gray fully mediated the association between schizotypy and antisocial behavior. After having controlled the sex, age, socio-economic statuses, whole brain volumes and substance abuse/dependence of test subjects, the orbitofrontal gray still significantly mediated the effect of schizotypy on antisocial behavior by 53.5%. These findings are the first that document a neural mediator of the schizotypy-antisocial behavior relationship. Findings also suggest that functions subserved by the OFC, including impulse control and inhibition, emotion processing and decision-making, may contribute to the above comorbidity.

Association between cannabis use and schizotypal dimensions--a meta-analysis of cross-sectional studies

Cannabis consumption can cause abuse and dependence and increase risk of developing psychiatric and somatic disorders. Several literature reviews explored the link between cannabis consumption and schizophrenia but none summarized the rich literature on cannabis and psychometric schizotypy. The aim of our review is to synthesize data from studies that explored the association between cannabis consumption and schizoptypal dimensions. A systematic review of the literature and, when needed, contact with the authors, allowed us to gather data from 29 cross-sectional studies. We compared schizotypy scores between subjects that never used cannabis and subjects that used it at least once ("never vs. ever") and between current users and subjects that do not use cannabis currently ("current vs. other"). We conducted separate analyses for total schizotypy score and each of the three classical schizotypal dimensions (positive, negative, disorganized). For all eight comparisons, the cannabis group ("ever" or "current") had higher schizotypy scores. Differences were in the small or medium range and, with the exception of the negative score in the current vs. other comparison, statistically significant. Cannabis consumption is associated with increased schizotypal traits. More research, using different approaches (e.g. longitudinal studies) is needed to explore the cause of this association.

Trait aggression, depression and suicidal behavior in drug dependent patients with and without ADHD symptoms

The objective of this study was to investigate trait-aggression, depression and suicidal behavior of drug dependent patients with and without ADHD symptoms. The cross sectional survey was conducted in outpatient drug centers in Hungary. The Adult Self-Report Scale (ASRS), the Buss-Perry Aggression Questionnaire (AQ), the European Version of the ADolescent Assessment Dialogue (EuroADAD), and the Beck Depression Inventory (BDI) were used for measures. GLM analyses, adjusting for age and gender, indicated that patients who screened positive for ADHD (ADHD+ group) had significantly higher severity of overall trait aggression, as well as physical and verbal aggression than patients who did not (ADHD negative group). The highest severity of aggression was observed when the ADHD+ status co-occurred with heroin use, while the lowest severity of aggression was detected when ADHD- status co-occurred with the use of marijuana. ADHD+ patients showed a marked increase in depression symptoms, suicidal ideation, suicidal attempts as well as self-injuries associated with suicidal attempts. Considering the substantial costs of aggression and suicide from a societal perspective and from the point of view of the individual sufferer, our results highlight the importance of the diagnostic investigation of ADHD in the treatment of drug dependent patients.

Differential correlates of reactive and proactive aggression in Asian adolescents: relations to narcissism, anxiety, schizotypal traits, and peer relations

This study investigated relationship between reactive and proactive aggression, and narcissism, anxiety, schizotypal traits, and interpersonal relations in a sample of 698 Asian adolescents from Grades 7 to 9. Proactive aggression was found to be significantly associated with narcissism, whereas reactive aggression was significantly associated with anxiety, schizotypal traits, and poor interpersonal relations. Study findings provide support from a cross-cultural standpoint for differential correlates of reactive and proactive aggression and represent an initial attempt to illustrate the generalizability of existing findings on the distinction between the two subtypes in an Asian context. Implications for theory building of the reactive-proactive aggression typology are discussed.