Tempeament and Character Traits of Personality in a Sample of Patients Admitted to the Emergency Unit with a Suicide Attempt

 

Mustafa Solmaza, Tuba Basoglua, Filiz Kulacaoglua,b, Ferhat Can Ardica,c, Yasin Hasan Balcioglud, Samet Kosee,f

 

a University of Health Sciences, Bagcilar Research and Training Hospital , Department of Psychiatry, Istanbul, Turkey, b Erenkoy Research and Training Hospital, Istanbul, Turkey, c Sirnak State Hospital, Department of Psychiatry, Sirnak, Turkey, d Bakirkoy Prof. Mazhar Osman Research and Training Hospital for Psychiatry, Neurology, and Neurosurgery, Forensic Psychiatry Unit, Istanbul, Turkey, e Hasan Kalyoncu University Department of Psychology, Gaziantep, Turkey, f University of Texas Medical School of Houston, Department of Psychiatry, Houston, TX, USA

 

 

Abstract

Background: In this study, we aimed to evaluate a sample of suicide attempters regarding temperament and character dimension scores and compare them with psychiatrically healthy individuals considering the influence of demographic risk factors.

 

Methods: This study enrolled consecutive 50 patients (39 women, 11 men) with a mean age of 24.12 (SD ± 8.83) years who were admitted to the Emergency Department of Bezmialem Vakif University hospital for a recent self- or not self-reported suicide attempt. The control group consisted of age- and gender-matched 50 healthy subjects (34 women, 11 men) who had not a documented axis I psychiatric disorder or a previous suicide attempt with a mean age of 26.46 (SD ± 5.6). A semi-structured sociodemographic and clinical data form, Structured Clinical Interview for DSM-IV axis I disorders (SCID-I), and the Turkish version of Temperament and Character Inventory (Turkish-TCI) were administered to all participants. Following screening of all variables for the accuracy of data entry, missing values, and homoscedasticity, statistical analyses were performed by using SPSS version 23 for Windows.

 

Results: A statistically significant difference was found between the patients and psychiatrically healthy controls mean values in terms of Impulsiveness and Disorderliness subscales of Novelty Seeking; Harm Avoidance and its all subscales, Sentimentality subscale of Reward Dependence; Self-Transcendence and its subscales of Self-Forgetfulness, Transpersonal Identification and Spiritual Acceptance scores were significantly higher in patients with suicide attempt compared to the control group. Patient group also exhibited significantly lower mean values of Self-Directedness, Persistence, and Cooperativeness scales compared to the psychiatrically healthy controls. 

 

Conclusions: In conclusion, our results suggested that patients with a history of suicide attempts  have abnormal TCI profiles linked to higher harm avoidance, novelty seeking and self-transcendence scores and lower self-directedness and cooperativeness scores compared to psychiatrically healthy controls. Since personality traits play an important role in the prediction of suicidality, clinicians should be aware of personality–psychopathology relations for  assessment and developing treatment strategies of  the patients with suicide attempt.

 

KEYWORDS: suicide, personality, character dimension, TCI, harm avoidance, self-directedness

 

 

Introduction

Suicidal behavior refers to a nosological penumbra that spans a range from death by a suicidal act, at the most severe and suicidal ideation, at the mildest verges (1). As such a complex phenomenon, suicide ranks among the major causes of death and accounts for approximately one million deaths worldwide annually with staggering public health burden and costs in socioeconomic and psychosocial contexts (2). In Europe, it is estimated that about 58,000 people die by suicide annually (3), and in Turkey, 1,772 deaths were reported as suicide incidents in 2017 (4). The high rate of suicide in younger population is one of the most worrying data, approximately a half of all suicide cases are the individuals younger than 45 years of age (5). Although roughly 90% of suicide cases had a diagnosable psychiatric disorder, mood disorders as the most common with a rate of 60% (6,7), many individuals with a psychiatric illness do not attempt suicide throughout their lives, which suggests the salient significance of the predisposition towards suicidal behavior that is independent of psychiatric disorders (1). Therefore, as the prediction and prevention of suicide are challenging and crucial issues, identifying and targeting high-risk groups require a more dimensional approach to understand the etiological underpinnings of suicide. Underlying mechanisms of suicide and suicidal behavior are heterogeneous and variable in terms of demographical, clinical, and neurobiological perspectives; therefore, the most applicable explanation that elucidates the etiology of suicide comes from the stress-diathesis model (8). This model provides an opportunity to integrate the contributory roles of distal factors that represent predisposition to suicide and proximal factors that refer to precipitating elements for suicide (9).

More than past twenty years, numerous research groups have focused on social, psychopathological, and neurobiological risk factors to reveal both distal and proximal contributors involved in the stress-diathesis model that leads to suicidal behavior. History of suicide attempt, male gender, older age, comorbid psychiatric illnesses including substance and alcohol use disorders, and serotonergic dysfunction with a number of neuroanatomical changes in brain structures are well-defined and established clinical and psychopathological predictors for suicide (8,10–14), while family history of psychiatric disorder and suicide attempts, childhood adversities, stressful life events, poor perceived social support and lower socioeconomic income are considered as psychosocial predisposing factors for suicidality (13,15–18).

Despite psychological autopsy studies have consistently demonstrated many of the suicide victims had been suffered from at least one axis I psychiatric disorder, given the fact of many of the psychiatric patients do not commit suicide has led researchers to approach to the understanding predisposition to suicidal behavior in a more complex manner. As suicidal behavior is an etiologically heterogeneous entity that consists out of a broad range of possible factor involved in its appearance and development, one of the most optimal explanations for the stress-diathesis model may be found in the underlying individual personality traits. Personality refers to a constellation of dispositional traits and characteristic adaptations that constitutes unique patterns of thinking, feeling, and consequent behavior (19). This set of inner enduring attitudes that mediate an individual’s emotional and cognitive processes and its potential pleiotropic influence on suicidal behavior has been attracted the researchers in the field for more than fifty years (20,21). Likewise, many of the personality disorders which represent enduring and pervasive disturbances and dysfunctional extremes of normative personality features, are associated with an increase in the risk of suicidal acts regardless of being a comorbid condition or single primary diagnosis (22–30).

Some studies using various personality assessment tools concluded that certain personality traits such as high neuroticism (24,31–35), high impulsivity (36–40), and low extraversion(24,32–34) were in relation with suicidal behavior risk. Nevertheless, the instruments employed in those studies raised concerns due to their limited strength to explain the common recognition that either genetic and environmental factors play distinct roles in shaping the individual’s phenotypic personality features (41). Therefore, the Temperament and Character Inventory (TCI) fulfils an unmet need as it provides a thorough evaluation of two core dimensions of personality; temperament and character. TCI is rooted in Cloninger’s multidimensional and psychobiological model of personality (42). This model evaluates seven higher order personality features, four of them as temperament dimensions which are reflecting the ingrained attitude of the individual toward the environment and constructed to correspond to underlying hereditary profiles of personality are; Novelty seeking (NS), Harm avoidance (HA), Reward dependence (RD), and Persistence (P). The three character facets of personality; Self-directedness (SD), Cooperativeness (C), and Self-transcendence (ST) refer to self-concepts and individual differences in goals and values that are assumed to be affected by maturity and social learning (43). Previous research has examined personality structure as represented in Cloninger’s personality model and measured temperament and character traits by TCI in patients who engaged in suicidal behavior. These studies revealed that high NS (44–47), high HA (48–53), low SD (45,48,50,52), low C (48,52) , and high ST (45,46) were in relation with suicide attempt.

 

An integrative approach to suicidal behavior as a distinct psychobiologic entity rather than a severe form of a time-limited psychiatric disorder would provide a deeper insight into the explanation of the combinational influence of demographic, clinical, environmental, and genetic factors on suicide. Identifying vulnerable personality traits in at-high-risk populations may shed light on the understanding the suicidal diathesis and help us to predict and prevent suicidal behavior. The majority of the studies that examined the influence of personality traits in suicidal behavior focused on the specific psychiatric disorder and their associations with personality dimensions. However, there is a lack of evidence that demonstrates personality profile in a suicidal population regardless of their axis I psychiatric disorders. Therefore, in this study, independent of the psychiatric diagnoses, we aimed to evaluate a sample of suicide attempters regarding temperament and character dimension scores and compare them with healthy control group considering the influence of demographic risk factors. We also aimed to validate prior findings that repeatedly confirmed certain personality dimensions such as high HA and low SD. We hypothesized that patients with suicide attempts are more harm avoidant, less self-directed and less cooperative than psychiatrically healthy controls are. We also address that numerous subscales of the main personality dimensions such as impulsiveness (NS) and fear of uncertainty (HA) score are higher in suicide attempters.

Methods

Study Participants

This study enrolled consecutive 50 patients (39 women, 11 men) with a mean age of 24.12 (SD ± 8.83) years who were admitted to the Emergency Department of Bezmialem Vakif University Hospital for a recent self- or not self-reported suicide attempt. The control group consisted of age- and gender-matched 50 healthy subjects (34 women, 11 men) who had not a documented Axis-I psychiatric disorder or a previous suicide attempt with a mean age of 26.46 (SD ± 5.6). After the required emergent medical care, the patients who were requested a psychiatric referral by the emergency department included the study after their written informed consents were obtained following a thorough explanation of the study procedure. Exclusion criteria included the following: aged under 18 or over 65 years, illiteracy or any socio-intellectual inability that impede give informed consent to or understand the study procedure, diagnosis of schizophrenia spectrum and other psychotic disorders, bipolar disorder, intellectual disability, dementia or other organic mental disorders, neurological disorders, alcohol and/or substance use disorder, being kept under observation in the emergency department or intensive care unit due to a subsequent medical impairment that requires medical care. The study was conducted in accordance with the ethical standards of the Helsinki Declaration of 2000. A semi-structured sociodemographic and clinical data form, Structured Clinical Interview for DSM-IV axis I disorders (SCID-I), and the Turkish version of Temperament and Character Inventory (Turkish-TCI) were administered to all participants.

Psychometric Instruments

Semi-structured sociodemographic and clinical data form. This form included detailed information of the participants regarding sociodemographic variables including age, marital and vocational status, level of education and family information. The form also included information about the patients’ suicidal method and previous suicide attempts.

Structured Clinical Interview for DSM-IV axis I disorders (SCID-I). This structured interview tool for assessing DSM-IV Axis I disorders is a clinician-administered instrument. It was first developed by First and colleagues in 1997 (54), and the reliability and the validity of the Turkish version of the tool were performed by Ozkurkcugil et al. in 1999 (55).

Turkish TCI. The TCI is a 240-item self-reported questionnaire with true-or-false statements developed by Cloninger to evaluate seven higher-order personality dimensions (42). There are four temperament dimensions as NS, HA, RD, and P and the three character dimensions as SD, C, and ST in the inventory. SD and C have five subscales, NS and HA have four subscales, and RD and ST have three subscales. The Turkish-TCI has been validated by Kose et al. in a Turkish sample of 683 healthy volunteers (56, 57).

Statistical Analysis

The data in this study were described using descriptive statistical methods (means, percentages, and standard deviations). Parametric variables in the present study were examined with the Kolmogorov-Smirnov’s test of normality. Following screening of all variables for the accuracy of data entry, missing values, and homoscedasticity, statistical analyses were performed by using SPSS version 23 for Windows.

 

Results

Sociodemographic characteristics of sample

    Sociodemographic characteristics of the participants were presented in Table 1. The average age was 24.12 (SD±8.83) in the patient group and 26.46 (SD±5.60) in the healthy control group. The patient sample consisted of 39 females (78%) and 11 males (22%) participants and control group consisted 34 females (68%) and 16 males (32%). Control group’s marital status was 64% single, 3% married and 2.9% divorced and patient group’s marital status was 74% single, 24% married and 2% divorced. There were no statistically significant differences between patient group and psychiatrically healthy controls in terms of gender, age, marital status (p>0.05).  

    There were significant differences between patient and control group in terms of employment, psychiatric admission and treatment history. Control group employment rates were 10% unemployed and 90% employed and patient group’s employed/unemployed rates were 36% and 64% respectively.

    Present psychiatric history rates for at least one psychiatric illness were 10% (8% depression and 2% anxiety) for control group. When the participants in the patient group were evaluated according to lifetime history of mental illness, 52% of the participants were diagnosed with major depressive disorder and 2% of them were diagnosed with an anxiety disorder. The participants in suicide group were also evaluated based on SCID-I (an inventory structured for the disorders at axis 1 of DSM-IV) 60% of the cases were diagnosed with major depressive disorder and 40% of them were suffering from a psychosocial distress at the time of their suicide attempt. Psychiatric admission rates were 4% for control group and 12% of patient group had psychiatric consultation and were continuing to their psychiatric treatment before their suicidal attempt.

    In our research 35 patients (70%) have not attempted suicide before, 24% of them had one attempt and 6% of the patient group had two or more suicide attempts. 98% of them committed suicide taking over-dose medication. There were significant differences between the patient group and the healthy control group in terms of self-mutilation behavior (p<0.05). 12 (24%) patients had self-mutilation behavior history and none of the healthy control group subjects had self-mutilation behavior history.

Comparison of TCI scales and subscales between suicide attempt and control groups

    The results revealed that there was a statistically significant difference between the patients and controls mean values in terms of Impulsiveness (Patient= 5.08, Control= 3.62) and Disorderliness (Patient= 5.78, Control= 3.74) subscales of Novelty Seeking; Harm Avoidance (Patient= 21.12, Control= 14.54) and its subscales of Anticipatory Worry (Patient= 7.70, Control= 5.06), Fear of Uncertainty (Patient= 4.50, Control= 3.78), Shyness (Patient= 4.10, Control= 2.54), and Fatigability (Patient= 4.82, Control= 3.16); Sentimentality (Patient= 7.52, Control= 6.74) subscale of Reward Dependence; Self-Transcendence (Patient= 20.48, Control= 15.48) and its subscales of Self-Forgetfulness (Patient= 8.5, Control= 5.42), Transpersonal Identification (Patient= 4.78, Control= 4.42) and Spiritual Acceptance (Patient= 7.2, Control= 6.68) scores were significantly higher in patients with suicide attempt compared to the control group (p<0.05). 

    Patient group also exhibited significantly lower mean values of Exploratory Excitability subscale (Patient= 5.68, Control= 6.98) and Extravagance subscale  (Patient= 4.26, Control= 5.06) of Novelty Seeking scale, Reward Dependence scale (Patient= 13.52, Control= 14.36) and it’s subscales of Attachment (Patient= 4.00, Control= 5.08) and Dependency (Patient= 2.00, Control= 2.54), Self-Directedness scale (Patient= 20.74, Control= 31.46), Persistence scale (Patient= 3.90, Control= 5.42), Cooperativeness scale (Patient= 24.28, Control= 30.38) compared to the control group (p<0.05) (Table 2).

Discussion

The principal findings of the present study were  patients with suicide attempt exhibit dramatically higher NS, HA, ST, and lower SD, C scores compared to psychiatrically healthy controls. These present findings were consisted  with literature. According to Gil et al., higher NS, HA, RD scores were reported in patients with suicide attempt compare to healthy subjects and both NS and HA play a major role in the prediction of suicide attempt behavior (58).  Perroud et al. reported significant higher scores for HA, NS, lower scores for SD (50). According to Pawlak et al., the patients with suicide attempt compared to psychiatrically healthy controls scored in the significantly higher HA, NS but significantly lower in the C (53). Lewitzka et al., also reported higher HA, lower RD, P in patients with suicide attempt (51). According to the  Eric et al., higher HA, lower P, SD, C scores were reported  in patients with affective disorder with suicide attempt compared to patients with affective disorders without suicide attempt (52).  However, there are contradictory views that NS is a protective factor to avoid suicide (24,48). According to Cloninger psychiatric patients with or without history of suicide attempt showed significant higher scores of HA and NS compared to the healthy population (59). According to the results of our present study, NS and HA appeared to be considered as a risk factor for suicide attempt. Cloninger et al., defined that individuals with  temperament profiles with high NS as impulsive, excitable and quick-tempered and high HA as cautious, tense, careful, fearful, insecure,negativistics (59). HA was significantly associated with depressive symptoms (60,61) and harm avoidance behaviors overlap with depressive symptoms (61,62). Although the combination of high levels of HA and NS is contradictory, Cloninger suggested that high harm avoidance explained depression, pessimism and high novelty seeking explained the urgency for acting out and facilitating the suicidal behavior. People who attempted suicide are characterized as aggressive or impulsive, hypersensitive, perfectionistic and tend to be withdrawn. Higher HA scores reflect the general psychopathology and may predict the higher risk for developing mental disorder. Thus, we can say that if pessimism and impulsiveness are at their highest the suicidality risk may be greatest. 

According to the results of present study, participants with history of suicide attempt had higher psychiatric history with depressive symptoms than participants without suicide attempt. But, most of the participants with suicide attempt did not have any psychiatric history before. These results may be interpreted as depression is not the only parameter that predict suicide attempt. Javdani et al., recently reported that personality dimensions are stronger predictors of suicide attempts than depressive symptoms (63). Thus, clinicians should evaluate suicidal risk with monitoring both personality factors and depressive symptoms.

According to a recent study, NS was found significantly and uniquely associated with suicidal behavior in patients with self-poisoning nonlethal suicide attempts (45). The socio-demographic pattern of this study were compatible with participants of our study that the majority of the participants were single females in early adulthood. According to Becerra et al., and Perroud et al., higher NS score is associated with suicide attempt and younger age of first attempt (50,64). These findings are consisted with our results that NS is associated with suicide behavior especially in younger ages.

Consistent with our findings decreased levels of SD, C scores and increased levels of ST were associated with the risk for suicide (49,65,66). SD has been linked to responsibility, purposefulness, productivity, self-acceptance. Low SD is related with aimless, lack of conviction, vulnerability to the environment (42) and is the major TCI correlate of Axis II pathology (67,68). Higher ST score with low SD, C score is characterized with  struggle with identity, absence of empathy, immature, suspicious behavior and  (69). According to a recent study that evaluted the relationship of TCI in remitted depressed patients with suicidal ideation and suicidal attempts; higher ST scores were found in patients with suicidal ideation and lower SD scores were found in patients with suicide-attempt group compared with the non-suicidal group . There were no differences in any temperament dimension of TCI (70). Smith et al., has been reported that high levels of C and SD may be protective against tendencies related with high ST (71). According to Cloninger, temperamental dimensions are stable and they do not change significantly with time, but improvement of character development is possible  with medication and psychotherapy (72). TCI is proven to show the effectiveness of the treatment and SD score can predict the degree of improvement and SD is a logical target for psychotherapeutic involvement (42,73).

We already know that neurochemical transmitters determine stimulus-response pattern as the foundation of the personality traits (42). Harm avoidance is associated with serotonergic imbalance (74) and dysfunction of the serotonergic system also has an important role in the genetic and neurochemistry of suicidal behaviour (75). Low 5-hydroxyindoleacetic acid (5-HIAA) concentration in the cerebrospinal fluid was found related to violent suicidal acts and upregulation of 5-HT1a and 5-HT2a receptors were observed in the prefrontal cortex (1,76). According to van Heeringen et al., patients with a history of suicidal attemps showed decreased 5-HT2a binding potential in the prefrontal cortex and this binding potential was significantly correlated with HA scores (75). In sum, central serotonergic function and HA can be associated with the probability of the occurrence of attempted suicide but further researches are need to clarify this relationship.

This study presented some limitations. First, the study has a small sample size. Since our study is a cross-sectional study, it can not make inferences about relationship between personality traits and suicide. Second, we did not exclude patients who had comorbid personality disorders. Further studies conducted in larger patient samples are needed.

In conclusion, this cross-sectional study suggested that patients with a history of suicide attempt  have a abnormal TCI profile linked to higher harm avoidance, novelty seeking and self-transcendence scores and lower self-directedness and cooperativeness scores compared to psychiatrically healthy controls. Since personality traits play an important role in the prediction of suicidality, clinicians should be aware of personality–psychopathology relations for  assessment and developing treatment strategies of  the patients with suicide attempt.

Declaration of interest:

The authors reported no conflicts of interest related to this article.

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