Egyptian Journal of Psychiatry

: 2018  |  Volume : 39  |  Issue : 1  |  Page : 15--22

Suicide risk and personality traits among Egyptian patients with substance use disorders

Mostafa Shahin, Ashraf A Fouad, Alia A Saleh, Aliaa Magdy 
 Psychiatry and Addiction Medicine Hospital, Faculty of Medicine, Cairo University, Cairo, Egypt

Correspondence Address:
Alia A Saleh
Lecturer of Psychiatry, Faculty of Medicine, Cairo University, 11431


Background The magnitude of the problem of substance use in Egypt has been growing lately. Substance use disorders (SUDs) have been associated with depression and suicide, as well as impulsivity and specific personality traits. Aim and Objectives This study aimed at evaluating suicide risk and its correlates in a sample of 40 substance users and 40 control subjects. Methods The severity of the addiction problem among substance users was assessed using Addiction Severity Index (ASI). Beck Suicide Inventory (BSI), DSM-5 Brief Personality Inventory (PID-5 BF) and Barrat’s Impulsivity Scale-11 were applied to both groups. Results The study showed that patients with SUDs had a higher suicide risk when compared with controls (P<0.05). They also showed higher impulsivity scores (P<0.05) and personality trait disorders (P<0.001) when compared with controls, particularly in antagonism (P<0.001), disinhibition (P<0.001), negative affect (P<0.05) and psychoticism (P<0.05). Conclusions Pathological personality traits may be associated with increased risk of suicide in patients with SUDs.

How to cite this article:
Shahin M, Fouad AA, Saleh AA, Magdy A. Suicide risk and personality traits among Egyptian patients with substance use disorders.Egypt J Psychiatr 2018;39:15-22

How to cite this URL:
Shahin M, Fouad AA, Saleh AA, Magdy A. Suicide risk and personality traits among Egyptian patients with substance use disorders. Egypt J Psychiatr [serial online] 2018 [cited 2021 Jan 19 ];39:15-22
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Suicide is a major public health issue, both in the general population and in those suffering from a drug use disorder. The prevalence of lifetime suicide attempts is estimated at around 3.6% among community samples. In comparison, the prevalence of lifetime suicide attempts for individuals suffering from heroin dependence is around 30% (Maloney et al., 2007). Suicide is one of the known mortality causes among opiate abusers, as attempt to suicide in opiate-dependent individuals is nearly 13.5 times more common than that in the general population (Wilcox et al., 2004).

Several studies in the literature showed that certain personality traits affected suicide risk among people with substance use disorders (SUDs) (Kornør and Nordvik, 2007). People with various SUDs seem to have a common personality profile; high neuroticism, low conscientiousness and low agreeableness (Terracciano and Costa, 2004).

Other studies showed a strong link between depression and the risk for suicidal attempts and the importance of assessing depressive symptoms when determining the risk for suicide in substance abusers (Aharonovich et al., 2002).

Impulsivity is defined as a predisposition toward rapid unplanned reactions to internal or external stimuli, without regard to negative consequences of these reactions to themselves or others. This is consistent with the notion that substance dependence is characterized by a tendency to select the immediate reward associated with drug abuse at the expense of severe negative future consequences including family, social, legal and psychiatric problems (Moeller et al., 2001). Impulsivity has also been linked greatly to suicide and suicidal behaviour. Higher levels of impulsivity were linked to more attempts (Dougherty et al., 2004).


This study hypothesizes that suicide risk in patients with SUDs is higher than that in substance-free population. It also hypothesizes that this suicidal risk is related to impulsivity and certain personality traits. The aims of the study were as follows: (a) to compare suicide risk between substance users and controls; (b) to compare impulsivity and personality trait domains between substance users and controls; and (c) to assess the relation between suicide risk and impulsivity and different personality trait domains among patients with SUDs.

 Patients and methods

The study consists of 80 Egyptians divided into two groups: the patient group, which included 40 substance users fulfilling the diagnostic criteria of SUDs according to the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) (APA, 2013) and confirmed by two consultants of addiction medicine attending in the outpatient clinic services or inpatient wards, and the control group, which included 40 controls with no history of substance use problem or psychiatric disorder who volunteered to participate in the study. All participants between 18 and 45 years of age and of both sexes were included. Patients with SUD were assessed after at least 2 weeks’ abstinence from drug intake. Patients attending the outpatient clinic services and patients admitted in inpatient addiction ward were both included. The following SUDs were included: alcohol, cannabis, hallucinogen, opioid, sedative/hypnotic and stimulant use disorders. All participants were subjected to urine screening for substance before assessment. The following patients were excluded: excited and uncooperative patients, patients in intoxication or withdrawal state according to the diagnostic criteria of the DSM-5, patients with comorbid psychiatric disorders in the form of schizophrenia spectrum and other psychotic disorders, bipolar and related disorders, major depressive disorder, substance-induced disorders and intellectual disorders.

Patients were subjected to the following:Semistructured clinical psychiatric interview of Kasr-Al Ainy Psychiatry Department: sociodemographic data, present history of psychiatric illness, substance use history, medical history, family history and present mental state examination with emphasis on the substance use history were obtained.Addiction severity index (ASI) (McLellanet al., 1993): the ASI is a semistructured interview designed to provide a multidimensional assessment of problems presented by patients with SUDs to guide initial treatment planning and to allow monitoring of patient progress over time. It is designed for use in inpatient and outpatient alcohol and drug abuse treatment settings. ASI (5th ed.) Arabic version was used in this study (Qasemet al., 2003).

Patients and controls were subjected to the following:Beck’s suicidal ideation scale (BSI) (Becket al., 1979): the BSI is a clinician-rating scale and is presented in a semistructured interview format. It is designed to quantify and assess suicidal intention. The scale was found to have a high internal consistency and moderately high correlation with clinical ratings of suicidal risk and self-administrated measures of self-harm (Becket al., 1979). An Arabic version was used (Alyet al., 2012).Personality Inventory for Diagnostic and Statistical Manual of Mental Disorders-5-Brief Form (PID-5-BF) (Kruegeret al., 2013): this PID-5-BF is a 25-item self-rated personality trait assessment scale for adults aged 18 years and older. It assesses five personality trait domains, including negative affect, detachment, antagonism, disinhibition and psychoticism, with each trait domain consisting of five items. The measure is completed by the individual before a visit with the clinician. Each item on the PID-5-BF asks the individual receiving care to rate how well the item describes him or her generally. The scale was translated and back translated into Arabic language after the authors consent was taken.Barrat’s impulsiveness scale-11 (BIS-11) (Pattonet al., 1995): the BIS-11 is a 30-item self-report questionnaire with responses in a four-point Likert-type scale. It has good validity and reliability. It measures three subtypes of impulsivity: motor impulsivity, attention impulsivity and nonplanning impulsivity. The three scores are summed to produce a total impulsivity score. An Arabic version was used (Agoub, 2005).

Ethical considerations

The study was approved by the scientific and ethical committee of the Psychiatry Department, Faculty of Medicine, Cairo University. Informed consent was taken from all participants. The researchers received no fund for completion of the study and they declare no conflict of interest.

Data management and statistical analysis

Data were coded and entered using the statistical package for the social science (SPSS, version 21; SPSS Inc., Chicago, Illinois, USA). Data were summarized using mean, SD, median, minimum and maximum in quantitative data and using frequency (count) and relative frequency (percentage) for categorical data. Comparisons between quantitative variables were made using the nonparametric Kruskal–Wallis test and the Mann–Whitney test. For comparing categorical data, the χ2-test was performed. The Exact test was used instead when the expected frequency was less than 5. Correlations were tested using Spearman’s correlation coefficient. P-values less than 0.05 were considered as statistically significant.


Demographic and clinical characteristics of participants

As regards the age and sex distribution of the participants, the patients’ mean age and SD was 29.09±6.92 years, whereas that of the control group was 28.00±6.71 years. Totally, 36 (90%) patients were male and four (10%) were female in the patient group, versus 33 (82.5%) male and seven (17.5%) female participants in the control group. [Table 1] summarizes the sociodemographic characteristics. As regards the type and duration of substance use, 15 (37.5%) patients were dependent on more than one substance at the same time (polysubstance dependence), whereas 12 (30.0%) patients were dependent on tramadol, 10 (25.0%) patients were dependent on heroin and three (7.5%) patients were dependent on cannabis only. The duration of substance use in patients ranged from 1 to 15 years, whereas the number of abstinent days at the time of interview ranged from 16 to 294 days. [Table 2] outlines the type and duration of substance use among patients. [Table 3] outlines the severity of the addiction problem in patients as measured using ASI subscales denoting the degree of impairment in medical health, mental health and social functioning. The presence of family history of drug abuse, severity of SUD and legal problems are also assessed and outlined.{Table 1}{Table 2}{Table 3}

Suicide risk among patients with substance use disorders

[Table 4] shows that the mean and SD of BSI for patients was 5.55+6.03, whereas that for the control group was 3.22+4.32. There was a statistically significant difference between the two groups (P=0.028).{Table 4}

Personality traits and impulsivity among patients with substance use disorders

The mean total personality dysfunction as measured using PID-5-BF for patients was 41.02+11.78, ranging from 14 to 65, whereas that for the control group was 29.50+10.97, ranging from 4 to 61. There was a statistically significant difference between the two groups (P<0.001) in overall personality dysfunction. There was a statistically significant difference between the two groups as regards antagonism, disinhibition and psychoticism (P<0.001, 0.001 and P=0.008, respectively). As regards impulsivity trait as measured using BIS, the mean and SD for patients was 73.20+10.80, whereas that for the control group was 64.73+10.39. There was a statistically significant difference between the two groups (P=0.001).

[Table 5] summarizes the comparison between patients and the control group in different personality domains. [Figure 1] shows the difference between the patient and control groups in antagonism, disinhibition and detachment domains.{Table 5}{Figure 1}

Correlation between suicide risk and personality traits

A positive correlation between total personality dysfunction (PID-5-BF) and suicide risk (BSI) was demonstrated; this correlation was highly statistically significant (P<0.01). There was a statistically significant positive correlation between negative affect, psychoticism and detachment domains and suicide risk (P<0.01, 0.01 and 0.05, respectively).

These correlations are outlined in [Table 6].{Table 6}


As for the type of substance used by patients in this study, 37.5% were using more than one substance, 30% were using tramadol, 25% were using heroin and 7.5% were using cannabis. Tramadol was the most prevalent substance in the sample of substance users in this study. This is consistent with many studies that claimed the increasing risk for tramadol dependence (opiates) in Egypt. This rise in tramadol may be attributed to the fact that people start using tramadol in an attempt to increase their work power and performance and not as an addictive substance. The low price of the drug and its availability lead to the rapid rise in its presence and consumption (Hatata, 2004; Abdel-Wahab et al., 2012).

Suicide risk in substance use disorders

Results of this study showed that patients with SUD had a higher risk for suicide when compared with controls (P<0.05). This is consistent with a meta-analysis of 42 cohort studies by Wilox et al. (2004), in which higher rates of suicide and death from suicide among substance users and drug addicts were found when compared with the general population. Substance-dependent individuals had an elevated risk for suicide, especially when entering into treatment (Yuodelis-Flores and Ries, 2015).

Substance-dependent individuals in treatment often enter with depressive symptoms and a number of severe stressors (relationship loss, job loss, health and financial problems) that put them at a higher risk for suicidal behaviour (Yuodelis-Flores and Ries, 2015). Moscicki (2001) stated that 90% of individuals who die from suicide suffer from depression or other mental disorders, a substance use disorder, or a combination of both {National Institute of Mental Health (NIMH), 2010}. The importance of these findings lies in the possible explanation of higher suicide rates among substance users compared with controls.

Several theories and hypotheses may explain why the two disorders (SUD and depression) co-occur in individuals at higher than expected rates. One of the most important hypotheses is a direct causal relationship, which postulates that the presence of one disorder may predispose to the development of the second (Kraemer et al., 2001). This explanation is often used to account for the comorbidity seen in alcohol and anxiety disorders and has been described as the ‘self-medication hypothesis’, where anxious individuals misuse alcohol or drugs to reduce distressing symptoms (Quitkin et al., 1972). Those who suffer from mental illness or psychological distress were often found to self-medicate with alcohol or other substances (e.g. drugs) as an inappropriate coping mechanism (Ford and Schroeder, 2009). However, some pieces of evidence suggest that depression occurs secondary to substance use. This may be explained by the dopamine depletion theory. Evidence supports the finding that depressed patients have low levels of dopamine in their brains (Meyer et al., 2006). Dackis and Gold (1985) suggested that cocaine as well as other drugs’ addiction stems from the depletion of synaptic dopamine in the mesolimbic dopamine reward system, leading to a dysphoric withdrawal state that drives drug seeking to restore dopamine to normal, drug-naive levels. In addition to the depressogenic effects of drugs and alcohol, the negative social and familial aspects of chronic substance use or excessive drinking may add to the risk for comorbid depression (Schuckit et al., 1997).

Personality traits in substance use disorders

Several studies on personality traits and substance use stated significantly high scores as regards several aspects of impulsive behaviour (Verdejo-Garcia et al., 2007) as well as personality traits and disorders (Zadeh and Damavandi, 2010) in individuals with SUDs.

Results of this study showed high impulsivity scores (P<0.05) and personality trait disorders (P<0.001) in substance users when compared with controls. When comparing specific traits, it was found that antagonism (P<0.001) and disinhibition (P<0.001) as well as negative affect (P<0.05) and psychoticism (P<0.05) were significantly higher in the patient group.

It is predicted that negative affectivity would align with five-factor model (FFM) neuroticism, detachment with FFM introversion, antagonism with FFM antagonism and disinhibition with low FFM conscientiousness and psychoticism would align with FFM openness (Trull and Widiger, 2013).

The high negative affect and disinhibition among substance users in this study were consistent with the high neuroticism and low conscientiousness, respectively, in the meta-analysis performed by Kotov et al. (2010). Sher (2005) stated that heavy users appear to score high on measures of neuroticism. Neuroticism reflects the level of emotional adjustment and instability. High neuroticism is associated with irrational ideas, reduced impulse control and poor management of stress (Costa and McCrae, 1992).

The high level of antagonism found in the results of this study was consistent with the low agreeableness level found in the study conducted by Ball on personality traits among substance users (Ball, 2002). Agreeableness is associated with positive interpersonal qualities such as altruism and positive attitudes toward others. These traits are not commonly associated with the hardened life of drug addicts (Dubey et al., 2010). Sutin et al. (2013) also stated that high neuroticism and low agreeableness were risk factors for illicit substance use. Psychoticism is characterized by tough-mindedness, nonconformity, hostility and impulsivity (Eysenck et al., 1985). High psychoticism and impulsivity among substance users found in this study is supported with similar results by Flory et al. (2002) and Shin et al. (2013), respectively. A tendency to be open to new experiences may lead people to try substances (Grossman et al., 1974).

Personality factors may interact in ways that lead certain individuals to become prone to engaging in health-damaging substance use behaviours. Moreover, consideration of interactions can potentially illuminate the important phenomenon of buffering effects. Personality traits may buffer one another in their effect on substance use in that a risk factor such as low agreeableness or high neuroticism may be mitigated by a protective factor such as high conscientiousness (Turiano et al., 2012).

For example, Terracciano and Costa (2004) found that adults scoring both low in conscientiousness and high in neuroticism were about three times more likely to be current smokers and substance users than those characterized by high conscientiousness and high neuroticism. A combination of high psychoticism (combination of low conscientiousness and agreeableness) and high neuroticism was predictive of heavier drinking (Patton et al., 1997).

However, results of this study were not consistent with other studies that revealed low openness to experience among substance users. This may be because substance users are not any more open to the new actions and ideas, which are among the openness to experience facets. They have narrow interest and imagination and muted in display of emotions. Substance users reported that they have lack of attentiveness to inner feelings and intellectual curiosity (Dubey et al., 2010).

As detachment aligns with introversion in the FFM, higher detachment results (introversion or low extraversion) were found among substance users in the meta-analysis by Kotov et al. (2010). It was hypothesized that introverted, depression-prone substance abusers are particularly attracted to drugs of abuse that possess analgesic properties (e.g. opioids and alcohol) (Conrod et al., 2000). Other studies stated high extraversion scores among substance users (Walton and Roberts, 2004).

Personality may be a critical predictor of suicide, as personality characteristics are formed in young adulthood and show stability across lifespan (Donnellan et al., 2015). Several studies have found different personality traits to be risk factors for suicide. Several studies were performed to assess personality trait domains’ relation with suicide using FFM. It has become important as the most recent DSM-5 includes an alternative model of personality domains, which have become important in clinical assessment (DeShong et al., 2015).

Chioqueta and Stiles (2005) found that suicide risk was predicted by high neuroticism, low extraversion and high openness to experience. Voracek (2006) found a significant relationship between suicide death rates with low conscientiousness and agreeableness. Results of this study showed a positive correlation between suicide and personality dysfunction (P<0.01). Negative affect (neuroticism) and detachment (low extraversion) were the significant domains in the study. When comparing specific traits, negative affect had a higher effect compared with detachment on suicide risk.

These results are in agreement with a recent study on the effect of five-factor traits on suicidal behaviour. DeShong et al. (2015) found that people with high neuroticism and low extraversion were found to be more susceptible to suicide compared with others. Moreover, they also showed that neuroticism played a larger role in suicide when compared with extraversion (DeShong et al., 2015). Mandelli et al. (2015) found that neuroticism was highly correlated to depression, suicidal ideation and attempts. Individuals high in neuroticism may be more likely to experience suicide because they are more vulnerable to experiencing negative emotions. Individuals high in extraversion may receive more social support due to their tendency to engage in activities that may involve other individuals. This may protect them from suicide as they will have an alternative to go to during the times of stress (DeShong et al., 2015).

Combining all findings and factors of personality trait domains with SUDs and the risk for suicide, it is very important to consider each domain as an inseparable part of the patient’s evaluation and assessment at the beginning of treatment to be able to maximize the help these patients can receive.


The sample size of this study was limited, and hence the results of this study cannot be generalized. The second limitation comes from the fact that cross-sectional retrospective designs do not allow establishing an evidence-based relationship or a temporal sequence between SUDs and suicidal ideations or plans.[50]

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.


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