The results of this study showed that several individual factors underlie suicidal behaviors in patients with BPD. Data analysis showed five themes and fifteen sub-themes. The five themes were categorized as follows: “psychological pain and loneliness”, “defects in the distinction and integration of emotions”, “unconventional behavior and emotion”, “pervasive incompatibility”, and “breakdown of the self-integrity”. The theme of psychological pain and loneliness in patients with BPD includes the sub-themes of worthless ego, mental fatigue, and feelings of loneliness and hopelessness. Many participants expressed that they felt absurd and worthless, they felt deeply alone, and were not understood by others.
To get rid of these feelings, patients with BPD commit self-injury and have suicidal thoughts. In Shneidman’s psychological model of suicide, psychological pain has also been considered a major psychological variable for suicidal behaviors (
25). In this regard, a study proposed that many patients with BPD, as part of their main identity, felt that they were inherently “bad”, “worthless”, or “unlovable” and that these attitudes motivated many self-injuring behaviors in BPD (
4). A systematic review in 2020 revealed that the experience of chronic absurdity might be related to the unique depressive experiences of the patient with BPD and be associated with masochism, suicide, and poor social and occupational functioning (
26). Another important theme of the study was “defects in the distinction and integration of emotions” in the emergence of suicidal behaviors, which included two sub-themes of “excessive emotion seeking” and “defects in emotional self-regulation”.
Emotion seeking, search for excitement, and various, new, and complex experiences, as well as the desire for bodily harm, were the experiences of this group of individuals, and participants stated that they were looking for excitement beyond usual and ordinary excitement. There are few studies on excessive emotion seeking, but in confirming the results of defects in emotional self-regulation, Fox et al. identified poor emotion regulation as a potential risk factor for the development and persistence of NSSI (
27). A study by Somma in 2017 found that emotion dysregulation was a significant mediator in the relationship between NSSI and BPD characteristics among adolescents (
28). Contrary to these results, Links et al.’s (study showed that the elements of emotional instability (fluctuation, maladaptation, and mood reactivity) were not associated with future suicidal thoughts and recurrent suicidal behaviors (
29), indicating further research in this regard.
In the present study, most patients stated that before the NSSI attempt, they had a severe state of internal and disgusting tension, after which they experienced a sense of calm and enjoyed seeing blood and self-injury. Andover also found the same results as the present study and stated that the most important motivation for NSSI in patients with BPD was to reduce stress and negative internal tension. Other reasons for NSSI include reducing unpleasant emotions, self-punishment, regaining control, and gaining awareness of physical emotions (
30).
Another theme was “unconventional behavior and excitement” with two sub-themes of “a history of substance use” and “having thoughtless and reckless behavior”. Many of the patients reported a history of psychiatric drug abuse aiming to calm down or attempt suicide, and also some of them reported a history of using various drugs and alcohol use. Indeed, one of the most important individual factors in these patients was drug, alcohol, and psychiatric drug abuse, which was effective in the development of suicidal behaviors.
The results of the present study are consistent with the results reported in other studies. In a longitudinal study, it was suggested that one-third of individuals with BPD used alcohol and drug (
4). The results of the national epidemiologic survey on alcohol and related conditions (NESARC) showed that 78.2% of individuals with BPD had lifelong criteria for a substance use disorder (SUD) (
31). Heath et al. also confirmed that individuals with BPD had a history of substance and alcohol abuse and also the severity of psychiatric symptoms such as depression, tension, anger, fatigue, and mood disorders were higher in these individuals and also they had legal problems and it was found that at the time of use, they had a high prevalence of NSSI including cuts (81.4%), strikes (36.7%), scratches, (33.3%) and burns (22.9%); overall, 50.9% of them perform various forms of NSSI (
32).
Another sub-theme in this section is “having thoughtless and reckless behavior”. Participants stated that they had explosive anger and did things without thinking about their consequences, which in many cases, led to increased suicidal behaviors. Findings of an eight-year longitudinal study at the University of Pittsburgh showed that higher degrees of impulsive aggression increased the risk of suicidal behavior, and also negative emotions, emotional instability, and impulsive aggression were among prominent personality traits associated with suicidal behavior in BPD (
4).
Behavioral norm-breaking (desire for absolute freedom, non-adherence to certain habits and behaviors, and lack of interest in frameworks and rules) and low tolerance threshold (low tolerance for stress, reactivity to the behaviors of others, and intolerance of failure) are two sub-themes of pervasive incompatibility. Patients stated that they were unwilling to adhere to a framework and rule because they were put under stress and then would engage in impulsive behaviors. In fact, these individuals have very low patience and tolerance and cannot adapt to new situations in different conditions. The results of a study showed that maladaptive performance was an immature defense style, more associated with personality disorder, and patients with BPD were more likely to use a maladaptive defense style and to attempt suicide (
33). Kofler stated that adolescents who experienced adversities had a relatively high level of emotional turmoil, eventually manifesting in the form of maladaptive behavior (
34). In line with the sub-theme of low tolerance threshold, it was found that another personality trait in patients with BPD was low tolerance, which in many cases was associated with suicidal behaviors. In addition, patients found distress unacceptable and intolerable and overreacted to stressors (
35). Another study also found that in patients with BPD, individuals with low distress tolerance had the highest risk of performing chronic and serious suicidal behaviors (
36).
The last theme extracted from this study was “breakdown of the self-integrity”, which included the sub-themes of “vulnerable personality”, “childhood trauma”, “poor problem-solving ability”, “ego weakness”, “unstable shaky identity”, and “emotionally insecure attachment”. Many participants reported that they started self-injuring behaviors at an early age, were emotionally and sexually abused in childhood, were raised in chaotic and insecure families, often felt the emotional absence of their parents, and felt distrustful of people. They also said that when their emotional and intimate relationships with their friends, especially the opposite sex, were destroyed, it created suicidal thoughts in these individuals; on the other hand, they were very vulnerable due to psychological traumas in interpersonal relationships, defects in communication, lack of strong emotional relationships throughout life, and rejection and lack of quality and stability of good emotional relationships, especially with the opposite sex. The therapists stated that ego in these people was not formed well, and they have a cognitive impairment such as poor problem-solving ability. The results of some studies have shown that BPD is a serious type of psychological pathology characterized by the pervasive pattern of instability in emotion regulation, dysfunctional interpersonal relationships, impaired identity, and a chronic feeling of absurdity, and identity dysfunction can lead to interpersonal relationships and behavioral disorders and exacerbate stress, incompatibility, and dysfunction (
37). Despite impulsivity and identity disorders in BPD, which are among more prominent factors in suicidal behaviors (especially gestures), child sexual abuse (CSA) seems to be associated with more serious suicidal behaviors (
38).
The findings of the present study demonstrate the complex and intertwined nature of traumatic experiences in organizing personality, self, and identity, and several participants stated that they had been sexually abused during childhood, and as a result, they were constantly stressed and anxious, had a bad sense about themselves, and then committed self-injury and suicide to get rid of these thoughts. Consistent with the results of the present study, Ibrahim et al. suggested that various types of maltreatment (sexual, physical, and emotional abuse) increased the risk of BPD and suicidal behaviors (
39).
In line with the sub-theme of insecure attachment, similar studies have confirmed that insecure attachment is particularly prevalent among individuals with BPD (
40), and this may confirm the hypothesis that the level of insecure attachment style is a mediator between BPD and self-injury (
41). Moreover, the results showed that patients with BPD have poor problem-solving. This finding is supported by the findings of Akbari Dehaghi et al. (
42). Also, consistent with this finding, meta-analytic studies on neuropsychological function have reported that individuals with BPD show deficits in a wide range of executive functions (EFs), including response inhibition, working memory, cognitive flexibility, decision making, planning, and problem-solving (
43). Some studies have identified factors such as depersonalization/derealization as factors influencing suicidal behaviors in BPD that were not seen in the participants of the present study (
44).
One of the limitations of this study was scheduling appointments with patients because they had daily visit schedules with psychiatrists and psychologists, which could cause fatigue and affect the process of interviewing the researcher, which this limitation was removed by the researcher’s long-term involvement in complying with patients’ plans to attend the psychiatric ward. Another limitation was related to the nature of qualitative research that the results cannot be generalized to the general public.
5.1. Conclusions
Individual factors and personality traits of patients with BPD (psychological pain and loneliness, defects in the distinction and integration of emotions, unconventional behavior and emotion, pervasive incompatibility, and the existence of self-spilt) play an important role in the incidence of suicidal behaviors. By identifying the underlying individual factors, appropriate preventive measures and interventions can be taken to reduce suicide-related behaviors such as suicidal thoughts and planning, as well as SAs. The results can also show planners and policymakers that qualitative along with quantitative studies can be used to take effective measures to reduce SAs in patients with BPD.